IMR Acoustics R1 - Reviews
Pros: Superb build quality
Good accessory set
Well-implemented audio filter system
Semi-useful port system
Extremely detailed and transparent sound
Brilliant bass tuning
Huge soundstage with good imaging
Cons: Design and DIY aesthetic is an acquired taste
Packaging does not reflect premium price
Thick and unwieldy cable
Fit is hit-or-miss
Average isolation
Subpar mids tuning, tone and timbre

I’ve lived in medieval times before. It’s true! I once did an internet questionnaire about it and watched Robin Hood: Prince of Thieves a few times. Back then, professions had a “smith” at the end, preceded by the one thing people were good at. So I’d probably be a wordsmith, Will Smith would be terribly good at writing wills, Robin Hood would be an Aerosmith, and Ron Sexsmith would likely be king of all the lands.

The medieval-talk was inspired by the steampunk design of the IMR Acoustics R1, which looks like an artifact of that era. Bob James, IMR owner, is the blacksmith and tunesmith of today. While not the most popular Bob (hard when you have Marley, Hope, and “the Builder” occupying top three), he cut his teeth in Trinity Audio, coming up with model after model and becoming essentially their spokesperson in Head-Fi until Trinity went under. He knew his stuff.

IMR Acoustics is Bob’s attempt to hit refresh, start anew, and kick ass again doing what he loves: making boutique in-ear monitors (IEMs) with incredible sound. The R1 is the fruit of his labour, a carefully crafted IEM that, according to the official site hopes to sound like an electrostatic headphone. It is also the only model offered by IMR so far, so R1 is both the entry level and flagship model. You go all in!

The R1 has a dual-dynamic hybrid driver setup: a 13mm ceramic driver paired with a 13mm beryllium driver with neodymium motors, capable of covering a staggering 14-40,000Hz in the frequency range. You might want to ask your doggo for help in this. It also has a dial in each earpiece that acts as ambient ports, and five audio filters to fine-tune the sound signature to your liking.

While not a technological marvel per se, the features alone outweigh the average IEM of any price. IMR is hopefully, having fun and taking things seriously in the IEM game again. Contradictory yes, but ask anyone who loves their job and business meets pleasure, leisure and... treasure I guess?

The R1 retails for £500 and is currently available through IMR’s official website. I thank Bob profusely for giving me the opportunity to review the R1, which was provided free of charge as a review sample.

This review was first featured in Headphonesty.

The soft glow belies the royal ear-smacking the listener is about to receive.

Equipment Used


  • Sony NW-WM1A "K" Modded, FW 2.0
  • iBasso DX-200 with AMP8
  • IMR Acoustics R1
  • Acoustune HS-1650CU
  • Empire Ears Legend X
Albums Listened
  • Bon Jovi – Cross Road
  • Daft Punk – Random Access Memories
  • Denean – The Weaving
  • Ed Sheeran – Divide
  • Fleetwood Mac – Rumours
  • Lorde – Pure Heroine
  • Melissa Menago – Little Crimes
  • Michael Jackson – The Essential
  • Salena Jones – Salena Sings J-Ballad
  • Simon and Garfunkel – The Essential
Packaging and Accessories

Sometimes at night, I leave the marital bed and retreat to the study for some furious reviewing. And sometimes, my wife would wake up and come a huntin’. If I was in the middle of an unboxing session and the packaging looked nice, yeah I get off the hook. Otherwise, well...

The R1 packaging would not survive this lol. It’s not an ugly packaging, but it’s obviously aimed directly at hobbyists. It won’t appeal to the casual bystander, or casual wife for that matter. The black and red box does have masculine flair, and the IMR logo is pretty nifty, but that’s about it. I’ve seen much better packaging elsewhere, but let’s move on. I just received an earful from the missus.

After unsheathing the black cardboard cover, an angry-looking red box greets you. Open the box, and the R1 says hello. You get a complete set of accessories too, some I’ll admit I might never use. There are 7 pairs of eartips (4 pairs of grey silicone in S/M/M/L, a pair of double-flanged white silicone in M, and 2 pairs of foam in M/L), a zippered hard case, shirt clip, 6.5mm adapter, cable, and the stars of the show, 5 pairs of audio filters with a metal holder.

For on-the-go use, the zippered case is large enough to hold the R1, cable, and all audio filters in the metal holder. One gripe is the metal holder has a crude finish, reinforcing the DIY aesthetic of the R1 rather than something more polished and high-end.

Assemble troops! Sonic attack imminent!

Design and Build Quality

Like polar bears, the R1 has a polarising design, but for the record I love it. The steampunk, industrial-inspired design speaks to me in different manly languages. The gunmetal colour makes me love it even more. It looks like what knights in glittery armour would wear to pump themselves up before jousting, in the good ol’ days.

The CNC engineered aluminium chassis is chiseled and smooth to the touch, with strong curves and a distinct poise. The dial that operates the port system has a sinister smile ala Watchmen. The R1 is built tough, and looks tough, like Jason Statham in IEM form. Just a brilliant masculine design through and through. I feel like chugging a beer, devouring red meat and wrestling a bear after coming in contact with the R1.


Since Trinity Audio days Bob is known to make his own cables rather than rely on stock, generic stuff. The 2-pin cable provided is made of Oxygen-free Copper (OFC), sheathed in a thick layer of TPU. From the connectors to the Y-split and the L-shaped jack, build quality is robust and made to stand the test of time (except hungry mouse attacks). However, ergonomics take a big knock.

The cable, being thick and hard to tame, tends to straighten itself. This means hooking the cable around the ear is quite an exercise. You’ll need to use the chin slider and have it pressed against the chin to hold the cable in place. If you intend to switch cables I have more bad news. The 2-pin sockets in the earpieces are 90 degrees rotated compared to other IEMs, so you can only use cables without earguides. Good luck in your quest.

Fit, Isolation, and Comfort

All-metal, I have bad memories of them. I pre-ordered Campfire Audio’s insanely popular Andromeda when it was first announced, and drove out to the post office to retrieve it because I simply. could. not. wait. Putting them on for the first time, I felt despair. The inside edges pressed uneasily against my ears, causing pain and pleasure in equal measure (it sounded excellent lol).

With that in mind, I approached the R1 with apprehension. The edges were smooth, but God the dial that controls the port system has some shiny sharp edges! Sweating, I put them on and... nothing. They sit perfectly in my ears, and the grim anticipation of getting my ears cut did not materialise. I dodged a bullet (more a knife), but can’t help but think that the dial might cause discomfort for others if the orientation was off by just a little.

Of the plethora of ear-tips provided, I was able to obtain the best comfort and seal with medium-sized stock grey silicone. With them, I wore the R1 for hours on end without issue. I do not feel the weight of the R1 in my ears, which despite its all-metal, imposing build, is pretty lightweight. I normally rely on aftermarket tips but not this time.

The “cogs” control the port system. I'm quite sure the O is for obsessive and the C is for compulsive. Smile!

Now, the port system. The dial that looks like a smiley rotates left and right to control how much outside noise enters, effectively controlling the level of isolation. The difference between fully open and fully closed are subtle but noticeable. I tend to leave it fully open for the biggest possible stage size and airiness, forgiving the small amount of outside noise I hear.

Fully closed, the sound becomes more focused and closed-in, although not playing to the strengths of the R1. The isolation is merely average even when fully closed, so I wouldn’t get this for daily commutes. I can think of only a handful of situations where you need the ports closed (library, hospital, ignoring the wife, dog, police). You might have your own reasons.

Sound Quality

With two dynamic drivers of exotic materials, you can be sure I’ll cook ‘em until they’re crispy and give off an otherworldly aroma. The R1 was burnt in with gentle music for 200 hours, giving the drivers a soft massage before dispatching them for full-time duty. After 200 hours it can be argued that the bass became tighter and punchier, while the imaging is a hair more accurate. Don’t dispute me.

The main setup used was Sony WM1A "K" Modded (low gain and Direct Source on) > stock cable > R1. I also took the R1 out for a spin with the iBasso DX200 but prefer the warmth and tonality of the WM1A rig.

Overall Sound Signature

If music paints a picture, the R1 is a bright red ‘V’ sign, expressing a valiant, vibrant tuning, versatile signature choice, vast staging, vivid imaging, and victorious execution. The overall sound signature of the R1 is unapologetically V-shaped, bringing deliciously-enhanced bass and a lifted treble. Another similarity across all filter choices is the epic-scale soundstage, which really can’t be ignored.

The acoustic filter system in a nutshell. Unscrew, rescrew, review.

IMR provides five audio filters to fine-tune your signature choice. The filters carry DNA from Trinity Audio days, and provide variety and play value. They are easy to install and switch, just a matter of screwing in (ooh) the nozzle of choice, which are colour-coded. IMR gave a rundown of each filter’s signature in their website, but naturally I prefer to use my own words.

The meatiest presentation, an ‘L’-shaped signature with super-prominent bass and treble, with mids not too far behind. The midbass is too rounded and bloaty for my taste.

Like black, still meaty and forward, but with the bass screws tightened, resulting in a classic people-pleasing ‘V’-shape. Fits most genres.

Bass on steroids. An overload of boominess at the lower regions for maximum warmth. However, bass bleeds aplenty and the overall presentation is congested.

IMR’s take on the Audeze sound. Treble is rolled-off early and bass not as impactful, resulting in a warm, smooth signature fit for (relative) easy listening.

The brightest, airiest signature with a midbass scoop and upper mids hump. Closest to neutral, normally my thing but hampered by an obvious metallic timbre.

To Summarise
Bass quantity: Copper > black > pink > orange > blue.
Treble quantity: Blue > black > pink > copper > orange.
My preference: Pink > orange > black > copper > blue.

My favourite filter is pink, and the rest of the sound impressions are written with the pink filter in mind. I also use the orange for lounging sessions and bouts of self pity. Let’s analyse the sound characteristics further.


The great Muhammad Ali had two skills: floating and stinging. The R1 bass does a bit more than sting, it pummels, but floats away gently as well. Depending on your filter the R1 bass varies from earth-shattering to mildly earth-shattering, and is a highlight of the IEM.

The subbass reach is tremendously low, rumbling and shaking like a trendy bottomless party. It moves air like making nobody’s business his business. The midbass has similar flair, deliciously full-bodied and well-layered. One half of the brain might ask, is this the ceramic or the beryllium driver working its magic? The other half will say “shut up and dance!”

Notes are thunderously impactful, with enough punch in attack to knock the wind out of you, like Ali. The best part is, right after the pummeling, notes decay into a beautiful flutter, airy and delightfully textured. Floats like a butterfly. Strength and agility rolled into one. It’s a gargantuan bass worth savouring over and over again, delicately gentle one moment and mercilessly lethal the next.


The mids have a tough act to follow, but get a good headstart. Despite the big bass, there is no bleed into the mids (except the boomy copper filter where everything just haemorrhages like an A&E department). The mids are placed a step back compared to the bass and treble, allowing the signature some breathing space and air.

First the good news, the mids are sufficiently transparent, airy and textured. Remember Bob's aim to have an electrostat-like sound? He's one foot in the pond here. You won't miss an ounce of detail, or if you live in Europe, a gram. R1 reproduces detail like it was second nature, and scoffs at lesser IEMs that cannot do the same.

Tonally though, I find them a misstep. While in every filter setting the mids are warmish and congruent with the bass, notes are bereft of fullness and body, especially in human voices. Woman-in-front-of-piano songs lack intimacy and allure, sounding emotionally distant. Voices have a ringing, nasal quality, like I’m listening to the reverb and echo more than the actual note.

Note length is unaffected, but it’s hard to shake off the 30% attack, 70% decay feeling. It’s like having an appetiser then straight to dessert. This is less apparent while listening to instruments, although the timbre veers towards a metallic tinge. I can’t help but think that in the pursuit of an airy, electrostat-like sound, note body and timbre are affected. You can't have it all.

Even amongst the gravel, the R1 just drips testosterone, like Clint frickin’ Beastwood.


At last we arrive at the treble. Down and on the ropes, Bob cracks his knuckles and proclaims, “showtime”. If the mids employed the rope-a-dope and absorbed all the damage it could take, the treble is the counterattack we’ve been waiting for. This is where the R1 shows its minerals and roars back into contention.

The treble is one for the ages. Airy, dynamic and extended for aeons, no matter what filter you choose you will hear the magnanimous treble clamouring for attention. Notes are delivered to you at hyperspeed, with a shiny, devilish sparkle. It’s like training for an upcoming pageant. Sparkle your way in, sashay, strike a pose, smile, sparkle your way out. Or maybe you’re Prince.

Oh the details, the texture, and the transparency level! It’s like the lid lifted off a boiling pot, or more succinctly a roof blown open. When Pharrell sings “clap your hands if you feel like a room without a roof”, yes he’s just heard the R1 treble. It has the speed and grunt to mine out the most minute of micro-details effortlessly. Attack and decay are precise and on point, cast against a hush-quiet background.

A nay-sayer interrupts, “is it sibilant?” And boy I have to tell you, our tastes might differ. I wallop treble like I wallop chilli, in high doses pretending it’s nothing, although in mortal pain. The treble here is unmistakably bright, and with the blue filter, prone to hisses and harshness. For other filters, the treble is a workhorse and a sparklehorse, with the occasional surprising zing. If you’re after a smooth treble, you’ve got the wrong review.

Soundstage and Imaging

You’re probably a regular working guy like me. Bound by the shackles of a 9-5 job, family commitments, bills to pay, a horrible secret that no one must ever know about, and a hobby to keep you sane. But at night, when you sleep, perchance to dream, everything is possible. The R1 won’t magically pay your bills and set things right (hell, it’ll plunge you further in debt), but listening to it sets you free.

In dreams, when you’re a lion, looking for a gazelle to play with in the plains of Africa; or when you’re Neo, flying across the city where everyone doesn’t know life beyond the Matrix. The R1 recreates this sense of freedom, of wide open spaces yet to be explored, and puts you in the middle of it, ready to play.

The soundstage height and depth are phenomenal, but pale to the awe-inspiring, jaw-dropping width. With the ports fully open (maximum freedom), you hear sounds in and all around you, melding with just a bit of outside ambience that acts like another injection of air. You think, this must be the neodymium motors pushing the sound as far away from your head as possible! I wouldn’t know.

As for imaging, positional cues are easily deciphered in all directions. The layering in the Z-axis is believable from front to back, while L-R positioning is near-flawless. Closing the ports brings the elements of the music closer, and imaging more solid, but nah, I’d rather the massive soundstage please. Your tastes may vary, of course. I’m all-in for the business of bigness.


Acoustune HS-1650CU

I heard the similarly-priced R1 and the 1650CU at an audio show and both wowed me. Unable to decide a winner then, naturally I acquired both for an intimate one-on-one. The 1650CU is one of the latest single dynamic IEMs rolled out by Acoustune, whose parent company Nippon DICS is responsible for creating Pentaconn 4.4mm jacks, so audio products are definitely in their DNA.

If we talk about everything but the sound, the R1 can pack its bags and go home. The 1650CU obliterates the R1 in packaging, design, build quality, accessory set, cable, and that special premium feel (also smell, touch, and even taste) inside and out. But here, sound quality rules supreme, and the R1 can yet redeem itself.

Just… so much bling in the room right now.

Signature-wise, the 1650CU is a warm monitor whereas R1 is more V-shaped. The magnificent R1 bass has quicker, punchier bass hits and decay, with more abyssal subbass rumble. The 1650CU is more midbassy, with thicker notes and a longer decay, which contributes to some warm air in the signature. The R1 takes the bass battle easily, but 1650CU returns the favour in mids.

Heck, 1650CU absolutely routs the R1 in mids. Tone, timbre, euphony, note richness, and most of all realism. Listening to Lorde gave me goosebumps, and I haven’t even begun listening to my diva collection yet. R1 might have the speed and detail levels in mids, but 1650CU sounds too close to the real thing to care.

Both trebles are executed well, with R1 punching air and details left and right, while 1650CU opts for a smoother transition with moments of excitement. It’s more a preference game. R1 takes control in the soundstage, with a bigger stage in all directions and a cleaner background, but more diffuse imaging. The 1650CU has more focused imagery, with fully-formed vocals and instruments.

In short, the 1650CU is able to deliver a more enjoyable, musical sound, with more meat in the bones, so to speak, and crazy-good mids. The R1 on the other hand has a more exciting, transparent and analytical signature complemented with some truly awesome bass.

Empire Ears Legend X

There’s the obvious price difference between the two, but when you talk about bass, the Legend X is never far, in fact he’ll come sprinting. As you might not know, I’ve awarded the Legend X the “Best Bass in the Universe” title, and like Miss Universe, he will spend the year doing humanitarian work and spreading the message of peace and goodwill. Yeah right.

Ace of Bass. All that she wants!

With its twin subwoofers, you can bet Legend X’s humanitarian work more resembles Street Fighter, battling worldwide and summoning Akuma if he accidentally got too good. So right off the bat, his aggressive, bass-first signature will hook you, delivering more slam and rumble than the R1, sounding “dirtier” with a longer decay yet agonisingly addictive.

The R1 for once, has a tighter and more disciplined bass, taking a less is more approach. Its more polite subbass and midbass means cleaner and airier hits, although they still possess thunderous impact. It’s actually an insanely close fight, but for those who know what I’m talking about, R1 has one of the best bass in IEMs, but Legend X, damn, it approaches the speaker realm.

From the mids onwards though, the Legend X truly flexes its muscles as one of the top IEMs in the market right now. He manages to sound more organic and natural while conveying equal amounts of detail as the R1. Notes are fuller and more accurate with lifelike texture, easily overshadowing the R1’s fragile tone and timbre.

As for the treble, Legend X clearly extends as far as R1, but stays pretty even without any particular emphasis. R1 treble while unquestionably detailed, sounds peaky and grainy in comparison. Its tinniness and slight metallic tinge are made more obvious compared to the smoothness and accuracy of the Legend X. R1 is trying his hardest but Legend X didn’t even break a sweat.

R1 does pull one back in the soundstage department. With fully open ports, they sound wider than Legend X, which already has one of the widest soundstages in custom IEMs. They are more or less equal in stage depth, height and imaging capability, but R1 is truly something special for the soundstage nut.

A wise man (ok I browsed the forums again) once said, mid-tier stuff shows you how amazing the top-of-the-lines (TOTLs) are. I tend to agree. The Legend X, while on a class of its own, has a pupil-dilating price tag to match. The R1 performs solidly in its tier, and is without a doubt the value-for-money buy.

Final Words

In any product line, there is a tendency to zoom into three distinct groups: the entry level to reel in the budget-minded or curious; the consensus value-for-money buy because everyone loves bang-for-buck (or just banging); and the top of the line… because you’re worth it <wink>. Everything else, unfortunately, falls by the wayside.

Flagship IEMs nowadays come in at an eye-watering, eye-gouging USD2000 minimum, increasing the need for a new category: the value-oriented TOTL. Something that you can be proud of owning, but will leave your bank account smiling (intact actually, who am I kidding here). Campfire Audio, CustomArt and Lime Ears are proud practitioners of this renegade group.

Verily, this I know. The R1 is a veritable sonic juggernaut.

You can count IMR R1 as one of the products f… I mean bucking the trend of super-costly TOTLs. Truth is, there is plenty to like about the R1. It is a boutique product with a design language that takes getting used to. But once you get past the DIY aesthetic, peel away the rough and tough exterior (figuratively!), the R1 eventually reveals its many charms.

Purely talking about sound, the show-stopping bass, football field-esque soundstage, and stratospheric detail levels will leave many in awe. It has an unabashedly bold sound signature that borders on the epic, and akin to a headphone experience in many ways. The switchable acoustic filters bring welcome changes to suit every mood as well.

The most unique thing about the R1 is the price. At £500 there are hardly any competitors in its price range that offers that much quality. The R1 is certainly keeping much more expensive TOTLs within its sights, and like the Jude Law sniper movie, pulls the trigger when you least expect it. There will be newer, more amazing products from IMR soon, but right now, the R1 deserves accolade and acclamation. Bravo.
Pros: Open and natural sound.
Cons: Could perhaps benefit from a little adjustment of the jack where the cable enters the housing.
Hello, I decided to make a Head-Fi account, so that I could add my opinion to the already well written reviews of the R1's. I will provide a short impression, as I am not practiced in reviewing, and have had precisely one pair of decent IEMs previously - my Ultimate Ears Triple.Fi 10s, which have been with me for nearly 10 years now.


First, a note on customer service. - I contacted Bob, prior to purchase, to enquire about postage details, etc. (I live in the UK). He responded within a couple of hours, and I found him to be helpful, and pleasant to deal with. My R1s were posted to me the same day, as I had ordered before 1pm. I received them swiftly, and in good order.
For info, I ordered the b+ grade.

Filter Tips first! (My impressions of the R1 sound are based on using these two types of tip, with no EQ from source, and unless stated, I run them with the vents in the open position).
Having had them for about a week now, listening to them as much as my free time allows. Regarding the tips, I have settled on my personal preferences;
Blue Tips: More airy, flat-type sound, which really accentuates complex, or treble heavy track and recordings, without skipping the reproduction of bass. (More similar to the flat tone of the Triple.Fi10s) These sound astounding on most of my music, but do not fit all of it.
Pink Tips: Slightly accentuated bass, but retaining firmly present mids and highs. These are more of an "all rounder" for me. They fit with the largest part of my music.

The R1 sound -
I was thoroughly impressed with the sound, right off the bat. I find them to be clear and open, and do not find them to over or under-accentuate any elements. What I find more impressive is how the sound is pleasingly full, and detailed, without feeling insistent or aggressive in the ear.
Bass, seems to be produced accurately and quickly. On the occasional electronic track, I feel the need to close the vents, which (I find after a second or two) tightens and accentuates the bass slightly more.
Mids, accurate, and unscooped, with good detail.
Highs, agile and responds well to source. They provide pleasant highs, and when the source contains forward or shrill highs (saxophone, some female vocals, etc), the R1s do not shy away from replicating that.

Overall sound - Clean, natural, and open - with the right amount of force of presence, when required.

A very enjoyable listen. I feel no fatigue from the sound.

Ergonomics -
Before we begin, let me explain that I have pretty large earholes, so do not suffer from any of the IEM issues our mouse-eared brethren may suffer from!

I find the R1s to be light,so they fit excellently with the large silicone tips, and feel secure in my ears. The only little niggle I've noticed during extended wear, is the length of the metal sheath on the end of the two-pin plug. I find that the long length of them leads to the over-ear cable-bend starting a little higher, and at a different angle, than I feel to be ideal. This means that I'm a bit more aware of the cable, just as it starts to touch the top of my ear. Personally, I'd prefer that sheath to be a bit shorter, and use a heavier cable.

The modules themselves sit nicely in my ear, with no pressure points, or feelings of force in my ear canal.

So, I find these to be very easy wearing, and not fatiguing, by sound nor fit.

Build Quality -
I have no concerns about the build quality. They feel and look well constructed. I feel no movement between the two halves of the housing, and the vent mechanism feels secure.

Looks -
If you like shiny things, these definitely fit the ticket! They look both dramatic, and intricate. The little grilles of the vents give me an 'analogue' feel, and remind me of the grille on a bass or guitar cabinet.
(I think I might be more of a sound man, than a looks man?)

Well, here endeth the ramble. :L3000::L3000:
Hope this has helped anyone who may be thinking about picking up a set.
Pros: High detail level (above its price level),
Effortless midrange presentation,
Great bass response (depending of the filter),
Lots of sound tuning options,
Solid build quality,
Good accessory package
Cons: The stock cable is too stiff and thick,
Possible fitting problems for smaller ears
IMR Acoustics R1
Someting unique...


IMR Acoustics is a relative young UK based brand, which was founded by Bob James with the main goal to create an In-Ear monitor that sounds like an electrostatic headphone, airy, detailed and with a wide soundstage.

IMR Acoustics Official Webpage:

This review was originally posted on my Review Blog, which I want now to share with the Head-Fi community:

Original Post:


The IMR Acoustics R1 In-Ear Monitor was provided to me by IMR Acoustics as a review sample. As always, I am not affiliated with IMR Acoustics or any third person beyond this review and these words reflect my true, unaltered, opinions about the product.

The Price:

The IMR Acoustics R1 is available on IMR Acoustics Webpage and is sold for around $665.00 USD under the following link.

Purchase link:

Warranty: IMR Acoustics is offering a 3 Year Limited Warranty

Package and Accessories:

The IMR Acoustics R1 came in a rectangular red card-box, which is wrapped with a black cardboard cover that sports the IMR acoustics logo and is containing the following items;

  • 1 pair x IMR Acoustic R1 Monitor
  • 1 pcs x Oxygen Free Cooper (OFC) 2 pin cable
  • 3 pairs x Gray Silicone Ear Tips (S/M/L)
  • 1 pair x White Silicone Ear Tip (M)
  • 2 pairs x Foam Ear Tips (M/L)
  • 5 pair x Sound Tuning Filters & Metal Filter Holder
  • 1 pcs x Hard Case
  • 1 pcs x 6.5mm Adapter
  • 1 pcs x Shirt Clip

Design and Build Quality:

The IMR Acoustics R1 is a unique and robust looking In-Ear Monitor (IEM) with a quite different design language. We can divide the IMR R1 into three parts; the main housing, which is made of an CNC machined aluminum chassis with gunmetal paintwork, the sound switch port, which is in silver color and also made of silver painted metal and the interchangeable tuning filter system.

The Main housing sports two screws, the 2pin female connector and left right markings. The sound tuning port (also described as rotating port) sports a markings (“C” for closed and “O” for open) that shows if the switch is in open or closed back mode. They are 5 sets of sound tuning filters that are all in different colors (black, blue, orange, copper and pick), which I will explain later.

The overall build quality is pretty solid, but it doesn’t looks premium like some other competitors in the same price class.

The Cable:

The IMR Acoustics R1 sports a detachable cable with 2 pin connectors that have a diameter of 0,78mm, which are more common than 2 pin systems with 0,75mm diameter. This 2 pin connectors have metal insertions that give a robust appearance.

The cable itself is made of an OFC (Oxygen Free Copper) wire material that has a tick and protective TPU coating.

The cable length is 1.4m and the 3.5mm 24ct gold plated headphone jack has a L angled profile.

This cable sports also a plastic chin slider and a metal Y splitter.

My first complain comes to the direction choice of the 2pin male connector, which makes the use of third party upgrade cables a bit problematic. My second complain comes to the thickness of the cable which is normally a good thing regarding to the protection, but which is a bit annoying if you try to wear the R1 over the ear.

Fit, Comfort and Isolation:

The IMR Acoustics R1 can be categorized as IEM of the larger side, because the solid aluminum housing is pretty big, but doesn’t feel heavy when inserted to my ears. It should not be problematic for ears with an average size like mine.

The IMR Acoustics R1 normally is fairly comfortable, but the cable is a bit annoying due its stiff and thick nature, which is causing to irritation after a while. I have found a solution, when you wear over your ear with the help of an ear-hook, the comfort issue disappears completely. Bad that IMR Acoustics didn’t have included a set of ear-hook to the package.

The Isolation is above average and there is no noticeable or better to say dramatic change, even when the rotating port is in open position.

About the Hybrid Driver Unit:

The IMR Acoustic R1 sports a custom made 13mm diameter Ceramic hybrid driver unit. This ceramic driver is combined with a 13mm dynamic driver that has neodymium motors, which supports a frequency range between 14- 40000Hz to cover the whole audible range of audio.

According to IMR Acoustics; the ceramic driver inside the R1 is not as power hungry like the competition and has a relative low impedance of 32 Ohm.

As mentioned before, the R1 also incorporates a switchable open and close port on the rear of the in-ear monitor to allow changing the staging or isolating from the world outside when required.

In addition the R1 is supplied with 5 audio filters to allow you to tweak the tuning to your individual style. These audio filters allow you to alter bass levels, treble levels and increase midrange response as required.

Technical Specifications:

  • Driver Type : 13mm driver featuring Neodymium motors with beryllium diaphragm + Ceramic driver
  • Sound Porting : IMR Open and close porting system
  • Impedance : 32 Ohm
  • Sensitivity : 108 +/- 3DB
  • Frequency response : 14 – 40000Hz
  • Headphone Jack : 24ct Gold plated 3.5mm Jack
  • Connector Type : 2 Pin detachable cable
  • Cable Type : Oxygen Free Cooper (OFC) Cable

Drivability (Impedance):

The IMR Acoustic R1 is a relative easy to drive In-Ear Monitor with a rated impedance of 32 Ohm’s and there was only the need of extra volume with the orange and cooper filter.

This feature makes the R1 ideal for the use with portable sources like Smartphones, Tablet’s or DAP’s with a relative weak amplification.


a) In Ear Monitor : IMR Acoustics R1, Campfire Audio Polaris

b) DAP/DAC :
Cayin N5II, Chord Mojo, Hidizs DH1000, Fiio Q5

c) Albums & Tracks used for this review:

  • Jehan Barbur – Yollar (Spotify)
  • Minor Empire – Bulbulum Altin Kafeste (Spotify)
  • London Grammar – Interlud (Live) (Flac 24bit/44kHz)
  • Laura Pergolizzi – Lost On You “Live at Harvard and Stone” (Tidal Hi-Fi)
  • Steve Srauss – Mr. Bones (Flac 16bit/44kHz)
  • Dire Straits – Money for Nothing (DSD 64)
  • Gothart – Jovano, Jovanke (Spotify)
  • Otto Liebert & Luna Negra – The River (DSF) – Binaural Recording
  • GoGo Penguin – Fanfares (Tidal Hi-Fi)
  • Adam Taylor – Colour to the Moon (Flac 16bit/44kHz)
  • Casey Abrams – Robot Lover (Tidal Hi-Fi)
  • Liquid Tension Experiment 2 – Acid Rain (Spotify)
  • Opeth – Damnation (Tidal Hi-Fi)
  • Megadeth – Sweating Bullets (Flac 16bit/44kHz)
  • Metallica – Sad bu True (Flac 24bit/96kHz)
  • Future Heroes – Another World (Tidal Hi-fi)
  • Lorde – Team (Flac 24bit/48kHz)
  • Tom Player – Resonace Theory “Album” (Tidal Hi-Fi)
  • Deeperise feat. Jabbar – Move On (Spotify)

Sound Analysis and Comparisons:

a) Short Description of the Sound Filters according to IMR Acoustics:

  • Black Filter : Maximum attack with impactful bass, richer mids and controlled highs
  • Pink Filter : Slightly decreased bass from the black filter with the same mids and highs
  • Copper Filter : Maximum bass, lush mids and slightly recessed highs
  • Orange Filter : Balanced bass and mids with rolled off highs
  • Blue Filter : More balanced across the range, natural and airy sound with perfect mid and sub-bass

PS: I have burn-in the IMR Acoustics R1 for a approx 150 hours due the Ceramic Hybrid configuration, which should need more time to show its true potential. I have used the stock gray silicone ear tips, which came inside the package of the IMR Acoustics R1 and the filter in pink color will be my reference filter.

b) Sound Signature and Tonality:

As I mentioned before, the IMR Acoustics R1 has a wide variety of sound tuning filters that can drastically change the tonality and frequency response. The user has the possibility to choose one of the five filters supplied according to his taste.

IMR Acoustics R1 provides a warm, neutral, energetic, full or vivid tone signature and presentation through the filters. Since there is a radical sound difference between the five filters, I will try to compare it with each other.

The Pink Filter:

The Pink filter has a linear bass emphasis and sounds fast, energetic and detailed. It’s very natural with percussion instruments such as drums etc. to be used in metal music. The overall speed and detail representation is quite successful.

The bass amount of the Pink filter will probably not be sufficient for bass heads in music types such as Pop or EDM, but is quite enough for natural instruments. The bass has a good depth display, but the extension is a bit shorter than the other filters, such as black and copper filters.

The midrange of the Pink Filter sounds very balanced, clean, energetic and transparent. Instruments sounding very lifelike and the level of detail reproduction is above its price range.

Vocals are successful and the tonality is pretty natural. The coloration level is very low and the lower midrange sound more balanced than the copper filter.

Female voices have a pronounced emphasis on the upper midrange and sounding spacious detailed and vivid.

The treble of the pink filter have good extension without any remarkable ear piercing. Some Instruments such as woodwinds or bells sounding crisp, detailed and lively.

The only noticeable considerable distress is that the treble sounds sometimes metallic and slightly cold. Otherwise the heights are technically successful.

The Black Filter:

The black filter has the most coloration among all filter and has a V-shaped sound signature. The lower frequency range is dominant and the treble is less detailed compared to the pink filter.

This filter shares a deeper and more dominant lower frequency depth; moreover the bass is more controlled and has a good decay. It’s superior in terms of quantity and depth to the Pink Filter, but can not keep up with its speed.

In the Black Filter, the instruments are slightly positioned in front of the vocals and the male vocals can sometimes mix. However, I have not found such a situation with female vocals. The midrange of the Black filter sounds colored, warm and bright, but the Pink Filter has more detail to offer.

The sound on the black filter is tuned for comfortable listening, but is missing some energy and liveliness, when it comes to the treble presentation. The treble extension and sharpness of the black filter is behind in performance and don’t sounds as airy and clean like the pink filter. In short, the black filter is slightly lacking in airiness and for the brightness, but is an ideal filter for long listening periods.

The Copper Filter:

The Copper Filter has the highest amount of bass among all filters and is perfect for Bass-head’s. This filter is superior in terms of bass depth and amount to the black filter, but the bass presentation dominates the R1 presentation to a high degree.

Although the copper filter is more successful in terms of bass amount, depth and extension than the other filters, but the speed and detail reproduction is inferior to the blue and pink filters.

The mid-range sounds fuller, thicker and shares more body than the black and pink filter. But the mid-frequency region is not as detailed and airy as the pink and blue filters. The most salient feature that is forgiving while listening to female voices.

The treble range of the copper filter is less detailed and forward than the pink and black filter.

While the treble detail could be enough for bass heavy genres, it may not be enough for other genres. The copper is less successful in terms of airiness and spaciousness than the Pink filter, but don’t get me wrong, it doesn’t sounds completely airless.

The Orange Filter:

The orange filter has the warmest sound signature among all filters and sounds thick, full and controlled.

The bass amount and depth of the orange filter is inferior to the copper filter, but superior to the blue and pink filter.

The midrange of this filter sounds more spacious and detailed than the copper. The midrange has also a wider volume than the copper, but the detail reproduction and separation of instruments is inferior to the pink filter.

The treble of the orange filter has the less airiness and extension, and is also suitable for long listening periods.

The Blue Filter:

The blue and the pink filters are the most balanced sounding in this collection. The blue filter has a relative linear and neutral bass character, but is inferior to the pink filter in terms of bass depth and emphasis. This filter is especially suitable for music types that require a high bass speed.

The midrange performance of the blue filter is slightly behind the pink filter, but is superior to the rest in the collection. The midrange sounds pretty neutral, lively, clean and spacious.

Although the midrange is a bit more backwards compared to the pink filter and the

Vocals are not as accentuated as the pink filter. But if we compare it with the rest of the filters it sounds more detailed than all the others.

The treble range of the blue filter is slightly behind the pink filter in terms of extension, sharpness, control, speed and detail, but is superior all other filters.

There are no negative situations like sibilance or mixing and the airiness and freshness of the treble range is also remarkable and successful.

As a result, the IMR Acoustics R1 offers its users a wide range of sound filters, which we could descript as vocal, bass, linear, musical and reference filters.

f) Soundstage:

The IMR Acoustics R1 has in general a relatively large soundstage for an In-Ear Monitor and spreads the instruments pretty well over this stage. The R1 is performing slightly better regarding to depth, but please don’t get me wrong, the wideness of the stage is also pretty good at all.

g) About the Switchable Port:

It is possible to use the IMR Acoustics R1 in open or closed mode, thanks to the wheel pointing to points ‘O’ and ‘C’ on the back of the IMR Acoustics R1.

In open mode, the IMR Acoustics R1 has a larger bass range, especially with the blue filter, but the amount of bass decreases. In closed mode, the bass gains more in speed, depth, volume and emphasis than in open mode.

The Comparison:

IMR Acoustics R1 vs. Campfire Audio Polaris

Both In-Ear Monitors have similar price levels, while the IMR R1 has the advantage to change the sound signature and detail level, which can increase or decrease depending on the selected filter. The Campfire Audio Polaris is generally neutral and has a slightly dry and lively presentation.

The bass lines of Polaris are fast, energetic and accented and will be sufficient for most users except Bass-head’s. Polaris is more successful in the amount and depth of the bass than the black, pink and blue filters of the IMR R1, but shares a slightly lower performance than the copper filter.

The bass of this two IEM’s is pretty fast and controlled, but the speed of the blue filter makes the IMR Acoustics R1 superior to Campfire Audio Polaris.

Both In-Ear Monitor’s are sounding fairly lively and clean midrange. The detail performance of the IMR Acoustics R1 with the pink filter is superior to the Campfire Audio Polaris, while the Polaris performs better than the R1’s copper and orange filters.

The midrange of the Campfire Audio Polaris sounds recessed, while the positioning of the midrange is variable depending of the filter that is used.

Both IEM’s sharing a vibrant, well extended and detailed treble presentation. The detail in the treble range is a slightly better with the IMR Acoustic R1 especially with the pink filter, while the Polaris offers a better detail reproduction compared to the orange and copper filters. Both, the IMR Acoustics R1 and the Campfire Audio Polaris are sharing a good performance in terms of airiness and control in the treble range.

The IMR Acoustics R1 has a slightly deeper and also wider soundstage presentation than those of the Campfire Audio Polaris, while the Polaris has the upper hand for soundstage height.


The IMR Acoustics R1 is a very capable and flexible In-Ear Monitor with its unique sound switch port and very effective sound tuning filters. This flexibility and the detail level, which is on a level above its price point makes the R1 to great choice, for those who are looking for an IEM with different sound characteristics.

Pros and Cons:

  • + High detail level (above its price level)
  • + Effortless midrange presentation
  • + Great bass response (depending of the filter)
  • + Lots of sound tuning options
  • + Solid build quality
  • + Good accessory package

  • – The stock cable is too stiff and thick,
  • – Possible fitting problems for smaller ears

Perfect a review. Thanks my friend.
In my opinion, the imr r1 is a headset that plays above its price.
thug behram
thug behram
Great review! Could you please compare it DUNU DN-1000 and iBasso it01? I noticed you have or have reviewed all three. Thanks so much
@thug behram @karanehir35 Thank you for your nice compliments! The it01 and the R1 are very different sounding IEM's. The R1 is on a higher level, with it's price, detail and capabilities (filters etc.). The R1 sounds more effortless, especially in the mid-range and bass department. The it01 is a great budget IEM but has its limitations. So it wouldn't be fair to compare them : ) The DN1000 was a very old journey in the past so that I don't remember the sound anymore.
Pros: sound, fit, price, design (at least for me)
Cons: cables are reliable, but not the most comfortable
Ceramic drivers in the role of high-frequency tweeters in the portable audio are no longer a novelty; they were used by both the Japanese from Radius and the Chinese from 1More, wherein achieving excellent results in a treble area. However, I somehow did not find the model, which, in addition to the "tops" had well developed the other parts of the diapason. Now such model has appeared, so let's talk about it.
1-Main Pic.jpg

First of all, I'd like to thank IMR Acoustics for providing me a free sample in exchange to my honest and unbiased opinion.

IMR Acoustics R1 is an unusual model, using the hybrid scheme, combining a big 13 mm dynamic driver with the beryllium-coated diaphragm and a ceramic tweeter for high frequencies. The R1 also incorporates a unique switchable construction that allows to you change the type of earcups from closed to open (half-open, to be precise). Also, these IEMs have a detachable cable and allow tuning of the sound with the help of filters.

The cost of this model, of course, is no small, the R1 Price is 500 pounds, but going forward, I can say that in this case the cost is chosen correctly and matches what the buyer receives. Also, you can save pretty well, buying one of B-stock items, available on IMR's site with discount.

Design and comfort
One of the most fun features of R1 is the fact that in the photo (and partly in the video) they look worse than in life, which became one of the triggers for couch warriors who like to rate headphones by the photos. In reality, IEMs are attractive, with a slightly brutal design: everything is made of metal, assembled with screws; and looks a bit retrofuturistic. The build quality is quite good, but how they will behave themselves after a couple of years - only time will tell, but at the first impressions, they look entirely indestructible. Rotating covers for adjusting acoustic enclosure are pretty convenient even for blind control; they have a proper fix in the end positions (may be, of course, over time, they will become rickety, but this has not happened yet).

Despite the large size, R1 is comfortable in wearing; at least they fit without any problems in my ears, providing a long-term wearing comfort and the sound a little above average. During headphones wearing there is a slight driver flex, but careful handling helps to avoid problems.

The cable is made detachable and uses a two-pin connector with a bump for protection of the connection from incorrect polarity. Both stock cables (they are the same except for the plug) looks brutal, and they are the thickest non-twisted cables for IEMs.

At first, isolation seems disobedient, but over time it became softer. Of course, regular R1 cables can't be called ideal of ergonomics, but in fact, it turned out, that they are quite convenient in wearing, the microphone effect is almost absent. However, you'll won't have to worry about the durability of this solution.

Before listening, the headphones got 60 hours of burn-in, changes in the sound were during the first 8-10 hours.

Before talking about the sound, it is worth to say a few words about the possibility of its tuning. First, by rotating the outer parts on the case, we can change the cases between closed and open (it would be more precise to call it "not closed" or "semi-open"). Of course, it affects the sound isolation (not so much as it could be, by the way), the low frequencies and, as a result, a bit an imaginary stage. I use "open" option in the majority of cases, it is neutral, more balanced, and the imaginary stage is slightly wider (although the difference is not very big). In a noisy environment, a closed version comes to the rescue; firstly the isolation is a bit better. Secondly, the low frequencies penetrate through passive noise isolation most of all, so slight increase in LFs compensates external noise.
5-Side by Side.jpg

Secondly, you can alter the sound can with the help of filters. After trying out different variants, I've stopped at the blue, as the most balanced. If desired, IMR R1 can be turned into a very bassy model of outstanding quality, but I did not feel such a desire, so the review below is written for a neutral version of tuning.

With any tuning option, lows remain noticeable, but with blue filters, they have the best combination of control and impact. Bass has a perfect weight, staying pretty fast and offering great texturing. Lows go deep, almost reaching physical limit possible for IEMs. Of course, it isn't super-speed low frequencies of BA IEMs, but for the big dynamic driver, bass performs more than reasonable. That sense of well-controlled power that's what makes this so unique. When necessary, lows here can represent blows, implosions, thunder roar, when that's not required, they stay on their place, offering the great hint of warmth, adding realistic body to low-range instruments.

Mids are a bit smoothed, giving the lovely tint of realism to the R1's sound. These earphones don't try to make an accent on microdetails, but of course, the resolution is more than okay. Mids are emotional, with a pleasant level of energy and drive. The imaginary stage is spacious, with pleasant instruments separation, it's noticeably bigger than average both in width and in depth. Layering and instruments separation are also lovely and very realistic. IEMs don't try to make the sound more spacious then it is, so adequately mastered recordings will be a real plus.

Treble is another substantial part of this model. Highs have the perfect extension as well as layering and resolution. At first, IEMs without typical roll-off above 10 kHz sounds a bit unusual, but after some usage, you'll be surprised, how many small nuances you were missing before. Treble attacks and decays are also really lovely. From another hand, this IEMs are critical to material quality, some recordings have a weak upper treble area, and IMR R1 will clearly show that to you.

Few selected comparisons.

Dunu DK-3001 Dunu's hybrids are closer to neutrality and have a slightly better resolution, but lows and highs of R1 are more "tasty." Of course, it's subjective, but that's just my opinion. So, 3001 are a bit faster, but sometimes happiness is not in speed.

Campfire Audio Lyra II Lyra II is also a more neutral model tending towards monitoring representation. It offers less weighty lows with faster representation, but on the mids and treble R1 is a clear winner concerning engagement. Generally speaking, R1 sounds like a step from Lyra II towards Vega.

Campfire Audio Andromeda Well, of course, "Andro" is a better performer: neutral, but emotional, spacious, with better staging. From another hand, Andromeda's mids are dryer, and sometimes I can trade better technical characteristics for more "fun." Moreover, let's not forget about the price.

This headphones, of course, require a good player, wherein they have enough "potential" even for the top-tier solutions. Subjectively, I liked them the most with neutral players (iBasso DX200 or Ultima SP1000).

Style-wise, IMR R1 are universal, if you are satisfied with extended treble (not all genres benefit from that), the sensitivity to recording quality is above the average (especially over the upper frequencies).
8-Rear Port.jpg

Few tracks that I subjectively liked with this IEMs

Calvin Haris — One Kiss The work of the Scottish DJ perfectly demonstrates all the strengths of the headphones. Excellent elastic bass, clear middle frequencies, pleasant, treble effects and, of course, a general feeling of three-dimensionality — it is everything that is needed R1 to show itself from the best side.

George Michael — A Different Corner Looking with an unbiased glance, I can say that masters of pop music are well-known for their quality of the recordings, especially, if we talk about a live recording of a very emotional vocalist. IMR R1 does not pass on this material too; there is a beautiful staging, an excellent transfer of vocal emotions, full legibility of all instruments.

Massive Attack — Teardrop Of course, this is not a novelty, and the track is famous, but after listening to the track with the characters of today's review, I could not miss it. The signature corporeality in the presentation of the material turns both the piano and the accompanying vocal into a real feast for the ears and clearly outlined lows and light, extended treble complement the sound.
9-With Paw Gold.jpg

The complete harmony of content and appearance, quite a brutal case hides a forward, powerful sound with enjoyable tuning possibilities inside. Price, of course, I cannot call budget, but this is the case when headphones compete well in their segment and in many cases overperform it.

Pros: Wonderful Bass, Tuning Filters, Performance to Price Ratio
Cons: Cable Ergonomics
IMR Acoustics R1

IMR-R1 – Direct link to information

Purchase B-Stock - B-Stock purchase if available


A Little Technical Stuff:

· 13mm driver featuring Neodymium motors with beryllium diaphragm + Ceramic driver

· IMR Open and close porting system

· 5 Audio filters

· 2 Pin detachable cable

· Impedance: 32 Ohm

· Sensitivity: 108 +/- 3DB

· Frequency response: 14 - 40000Hz

· 24ct Gold plated 3.5mm Jack

· 1.4M length OFC cable

· Hard Case

· 6.5mm Adapter

· Huge selection of ear tips for the perfect fit



· Black - Maximum attack with powerful impactful bass, rich mids, and controlled highs

· Pink - Slightly decreased bass from the black filter with the same mids and highs

· Copper - Maximum bass, lush mids, and slightly recessed highs

· Orange - Balanced bass and mids with rolled off highs

· Blue - Beautifully balanced across the range, natural and airy sound with perfect mid and sub-bass.


IMR Acoustics IMR-R1

-MRSP: Universal fit £500.00 GBP/$663 USD at the time of the review

Sometimes available in B Stock – (currently £299.00 GBP - $397 USD)

I want to thank Bob James, proprietor of IMR Acoustics for providing me with the IMR-R1 for review.

Bob has been known in the industry for quite some time due to past affiliation with Trinity Audio. Bob’s company, IMR Acoustics, is a UK based company. The IMR-R1 is his current companies first go-round with an IEM and I will say they have made quite a royal splash, UK-Royal, get it? The IMR R1 has price positioned itself in the middle of the IEM tiers unless you are able to purchase a B-Stock which is quite a terrific bargain. However, while they may have priced themselves in the middle tier their sound quality can marginally compete with some upper tier offerings. I find the IMR-R1 has a great sound to price ratio.

I am not generally the person that has a lot of patience for “tweaking” sound, I guess I am more of a plug and play person. The IMR-R1 has taught me that experimenting with various filters and open/closed port combos were fun and worth the experimentation. In the end, I was able to find my sweet spot with an open port and the pink filter, but I also will say I enjoyed the default black filter almost equally as well.

The IMR-R1 is not without faults, as I will touch on later, but sound quality and the ability to engage the listener is not one of those faults.

A one sentence summary would be, the first offering from IMR Acoustics is a worthy listen.

A Little Marketing Hype:

The R1 is unlike any other universal in-ear monitor available on the market today.

Experience sound like never before with beautifully textured bass and lush midrange and highs that are present but not harsh.

Tuned to perfection using IMR's custom 13mm Ceramic hybrid driver unit. With its specialist hi-res ceramic driver combined with a beryllium 13mm dynamic driver with powerful neodymium motors for a huge soundstage and precise instrument placement and with an FR from 14-40000Hz to cover the whole audible range of audio.

Unlike other manufacturers using ceramics in this market that require high power to drive their units ours only needs 32 Ohm!

However, the R1's abilities do not stop there! The R1 also incorporates a switchable open and close port on the rear of the in-ear monitor to allow you to change the staging and shut off the outside world when required. In addition, the R1 is supplied with 5 audio filters to allow you to tweak the tuning to your individual style. These audio filters allow you to alter bass levels, treble levels and increase midrange as required.

The First Switchable Open and Close Port

The IMR R1 uses a unique switchable open and close port on the rear of the in-ear monitor, allowing you to change the staging and acoustic levels and shut off the outside world whenever you choose. This innovation is easily recognizable in quiet environments and is exclusive to the R1.

Fully Customize Your Experience

The IMR in-ear monitors are supplied with 5 acoustic audio filters allowing you to tune your IEM’s to your individual taste. These audio filters enable you to alter bass levels, treble levels and increase midrange to suit your personal preferences.





· 3.5mm to 6.3mm adaptor

· A semi-hard shell, zippered carry case,

· 3.5mm cable

· Eartips out the wazoo

· IMR-R1 monitors

· Filters and more filters

· Shirt clip


Unboxing and Accessories:

The accessories are plentiful. There are no cutesy items like wiping cloths or bags but the accessories that are included are exactly what is needed. A semi-hard, zippered carry case, ample ear tips in a variety of different styles and sizes and the sound filters. Originally a 2.5 balanced cable was included with the 3.5mm cable but the 2.5mm cable had issues and the decision was made to only include the 3.5mm cable. After the 2.5mm balanced cable was redone and issue free, I asked Bob if I could receive one and was promptly sent one. I have a 2.5mm and a 3.5mm SE cable, both being stock. I cannot think of anything else I would want as an accessory to further enhance my experience for that matter.

The explanation of the filters and what they attempt to achieve is listed above. The IEM’s are threaded as are the filters, so one must only unscrew whatever filter you are currently using and screw in one you would like to switch to. Very simple! Each and every filter is distinguished by a different color. The only issue is the fact it is difficult to decipher which is the orange and which is the copper, copper is the darker orange one, maybe green or some other color not so close, might have been a better choice.

I tried all of the filters and finally settled on the pink filters. I will say that “settled” may not be the correct choice of wording because out of my three favorite all seemed to be the “right one” at various times. I found the black(default), copper and pink to be my favorites. Keep in mind this is only my preference and YMMV and probably will.

Eartip wise, I decided on the JVC Spiral Dot L tips. They provided me with the best overall experience. I received a great seal and bass response and well as comfort with the JVC tips, and overall the best sound.

Now for the elephant in the room, the cable. Frankly, the cable sucks. It is rubber coated, uncomfortable, unruly, springy cable with a weird connector, to add to that, the cable doesn’t always want to stay behind the ears. The connector is a 2-pin so what could be so wrong? The pins insert into the IEM at an angle making it almost impossible to find one of your existing cables that will work. I hate the cable ergonomics and how it connects.

The cable should not enough deter anyone from buying the R1, as a matter of fact, I have worse cables in my collection, the Dita Truth, a $500 cable, has worse ergonomics. The sound of the cable is adequate, but the fact that it has a mind of its own is disturbing. The cable ergonomics do improve a little over time. In one of the online forums there are many folks mentioning that they have found aftermarket cables that provide comfort and fit inside at the angle and that they have fallen completely in love with the R1 with an after-market cable.


Build and Quality and Fit:

The IMR-R1 is quite an industrial, almost military looking IEM with metal screws and a brutish metal open/closed port dial. The R1 is neither large or small, the housings have a certain heft with its aluminum shell. The dial on the face of the housing is the main focal point as it is large and industrial with a notched edge. The bright chrome dial is designed to twist to give you either an open or a closed IEM depending on your environment. The nozzle itself is medium in length but extends further due to the fact that the filter threads into the nozzle end. The design is almost three pieces with the dial being one and both sides of the housing being two and three. The housing itself is a gunmetal color but with the huge dial being bright chrome it gives the illusion everything is chrome. On the side of the housing closest to your head, the monitors are labeled identifying the L and R and an IMR logo is emblazoned on the outside of the housing. The dial had some imperfections in the metal, I am usually very critical of imperfections but these have such an industrial design I wasn’t bothered.

The build quality is solid in its metal housing. I am sure they are not indestructible but they certainly have a feeling that they will be your companion for the ages. The only thing I question may be the threading where you insert the filters. Inserting and removing with time can cause the threads to become stripped and cross-threaded. These are only ramblings and possibly unfounded worries. Also, after initially playing around with filters you will more than likely settle on a filter that satisfies you and not swap them often. Also, remember the IMR-R1 has a three-year warranty.

A little more on the open/closed port dial. While it is a nice option, I found there to not be a staggering difference in sound quality between the open or closed position. Possibly, there is a bit more air in the open position but to me, it is not a huge night and day difference. It is subtle more than drastic. Also, the difference in isolation from outside noises is minimal.

Overall, I have zero-real complaints with the comfort of the IEM. They are about in the middle of the pack as far as comfort is concerned. I have had torture devices and some IEM’s I barely knew were in my ears and these are somewhere in between, if it weren’t for the cable, ugh! The nozzle has a slight upward tilt which happens to work well for my ears.

The IMR-R1 is a hybrid driver design utilizing a dual driver design. One being a beryllium13mm driver and the other a ceramic driver said to be a hi-res ceramic driver. I had no problem driving the IMR-R1 with any of the sources I have in my collection with the impedance being 32 ohms.

While I am not disturbed by driver flex I know many folks are and I want to tell you that driver flex is present and can be quite strong, especially upon insertion.


Review Setup:

This review was written utilizing multiple sources, Opus #2, LG V30, QP2R and Opus#1S. I listened using both a 3.5mm SE and 2.5mm balanced connection. I mostly utilized the pink filters and JVC Spiral Dot ear tips. My sample music consisted of 320kb and FLAC as well as streaming Tidal Masters, Spotify, and Deezer.

Moving on to the sound section….

The IMR-R1 is one of those IEM’s that comes out of the box and just smacks you into reality from the start, and it is a Godsmack. The default filter is the black filter and the R1 immediately begins to impress you with its prowess. It is a rich, snappy, bassy, with a up front and center aggressive sound. The R1 commands your attention and I admit it did get my attention. The IMR-R1 is not a smooth, Cohiba and Cognac type of IEM, not a warm, inviting s’mores around the campfire listen.


To effectively articulate the presentation and overall sound signature I would begin with aggressive, fast, furious, snappy, gritty and unapologetic. There is a tremendous amount of energy and snap in the signature. As I have stated I am using the pink filters which I felt had the most impact on bringing out the positive attributes and taming the most negative attributes. The R1 does not do much to try to tame music files that are prone to sibilance or harshness and to me it’s sharp aggressive delivery of the highs is one of the few negatives I can mention. The positives are without a doubt are the incredible bass that envelopes the listener and makes for a toe-tapping, head bobbing experience. An example of some of the music that will showcase the speed and presentation of the R1 would be EDM or specifically the likes of Infected Mushroom. That genre of music has a lot going on within the music and the R1 also seems to deliver at a frantic pace so they match quite well. While my description may conjure a manic display the R1 performs with the same level of intensity across the spectrum, so it delivers quite a balance. If you want immersion, play YYZ from Rush and take in all of the fast and furious bliss that the R1 is capable of. The R1 is an incredibly capable IEM.

The soundstage is very large and very well defined. Geometrically, It would be a large cube as it presents itself in more of a 3d fashion than a square. I think the fact the clarity of this IEM is superb lends itself to the encompassing feel that there is so much air around the notes. It certainly has one of the largest stages I have encountered. Worth mentioning is the fact that to my ears the entire delivery is so in your face. When listening you can forget feeling you are two or three rows back from the stage, with the R1 you are exactly at the stage. I feel even with the pink filter everything is in your face, and some of the filters make this effect more pronounced.

I would classify the tonality and timbre to be average. The R1 has showcased other qualities in which it excels but the tone and timbre have a slight metallic sound, and those characteristics are placed mid-way through the list of specific qualities pertaining to the R1, with instruments sound ing realistic but their timbre being off. I am highlighting what I hear, but I do not wish to sound as if there are any glaring defects that would be considered deal breaking. I think the fact the treble extends so darn well really overshadows any artificial tones. The delivery is not spastic or out of control, in fact, I find it very controlled it is simply the tuning of the R1 and I feel Bob is presenting us the music exactly as he intended to.

Each frequency range is clear, defined and well presented. Nothing bleeds or interferes with the providing you with clear definition. While there is a strong, snappy bass presence there is no real feeling of warmth or smoothness. Some adjectives that would not describe the R1 are lush, smooth, warm.


The bass is the driving force of the R1 and clearly, it is my favorite part of the signature. It is a thunderous yet fast, snappy bass. The sub-bass kicks with a jaw-rattling force, especially with the copper filters. The Red Hot Chili Peppers, By The Way, is a delightful listen to get a feel for the intensity of the bass. What the heck, anything by the Red Hot Chili Peppers and Flea is awesome with the R1. The bass in the R1 is proud of its weight and it flaunts its girth without any loose or flabby notes. It is crisp and defined, to say the least. I am a huge fan of Dynamic Driver bass and the R1 certainly carries on that DD tradition. All of the bass frequencies are clearly represented and accounted for. Definition and resolution of the bass notes are what you can expect while having a serious impact that the listener can feel as well as hear. I feel the pink filter may decrease the sub-bass somewhat. There is a sharp decay and you won’t find any lingering notes. The bass of the Dita Dream is still at the top of the heap of the DD’s I have heard, based at the time I received the R1, but this would certainly be a close second and first in terms of impact with the Dunu DK-3001 also thrown somewhere in the mix.


Depending on the filter used, the mids can be very front and center. I think the pink filter is a little less aggressive than some of the others. The pink filters may produce a slight dip in the lower mid-range. There is no decline in the amount of clarity or details in the mid-range and as previously mentioned the separation is huge. Possibly, because the pink filter appears to slightly lessen the sub-bass it creates the illusion of increased clarity and detail. There is nothing analytical or fatiguing about the mid-range of the R1 in that it is not the most micro-detailed but the clarity is phenomenal. There are adequate details revealed but you won’t have fatigue over long listening sessions due to an overabundance of detail. To me, some of what you can achieve from the mid-range is going to be based on the music you throw at it. Meaning, the R1 has a capable mid-range and if the music is complex and detailed then that is what you will hear.


This is the part of the signature I wrestle with the most. The treble extends well and has a very aggressive shimmer. The treble certainly aids in producing the awesome soundstage and delivery of details but yet there is something metallic to me in the tone. It is not really a natural timbre and I think that is part of the perception of the in your face highs. They say perception is reality and to me, that is the reality, I enjoy the overall IEM immensely but I cannot effectively articulate my feelings towards the treble without sounding negative. Nothing is truly offensive here nor would I say that the treble is troubling but it is the weakest link to the entire signature. I am hesitant to say the R1 is a bright IEM because I found balance with the pink filter. The copper filter appeared to lessen the treble a bit more but I enjoyed the extension and width the pink filters provided me. As I said before if you have music that is sibilant the R1 will do nothing to smooth out the rough edges. You can expect details and clarity and I am being critical, because I love how the treble creates a balance and harmony throughout the entire range. Some of the sources, such as the Opus #1S, with its smoother tone and rich full sound, helped cure what I feel ailed the R1. Listening to Dire Straits Sultans of Swing, the cymbal hits can be a touch overbearing.



The R1 doesn’t need a great deal of power to drive but with some extra power, it will certainly excel. It is an IEM that realizes the sweet spot between well powered and underpowered, meaning that I found its aggressive nature to be fatiguing with too much power, just overbearing. I want to say that I have tried to become more volume conscious lately as I am trying to preserve my old ears and hearing. I have found that while it is really enjoyable to bump up the volume on occasion it probably isn’t the best for the hearing. I know it is not an earthshattering bulletin that loud noise damages hearing but it is becoming my reality.

All of my sources drove them perfectly fine and while most of my sources have a more neutral to slightly warmish profile, except maybe the Shanling M3S, I found it is indeed the neutral to warmish signature that works best for my needs. I would say that tone and organic sound might be what you should seek in a DAP to find your ultimate pairing.

My least favorite pairing of the sources I utilized to write the review would be the LGV30. I did not feel it provided the tone and body that the aided in smoothing out the rough spots with the R1.

My favorites were the Opus#2, Opus#1S, and the QP2R. The Opus#2 has a slight edge because of the warmth in its signature. The Opus#2 is very organic and has been my reference DAP for quite some time now. As I will mention in another review, it has been replaced as my reference by the QP2R but I still found the Opus#2 to be a slightly better pairing with the R1. The stage remains immense and the slight warmth, in all of the right places seemed to mesh so well with the R1.


The Opus#1S has such a full, rich sound with a very cozy tone that it was really a match made in heaven for the R1. It lacks a little resolution that the Opus#2 offers but the pairings tonality is truly hard to beat. For the $600 difference between the Opus#2 and the Opus#1S, with the 1S being the less expensive, I do not think you can go wrong with this pairing. For $400 for the Opus#1S and a B-Stock R1 for around the same price, it is quite a formidable combination.


To you QP2R owners or anyone considering the QP2R you will not be disappointed, but I found that the amount of power the balanced output delivers, you can easily listen at lower volumes. The sound is not quite as warm, as the slightly warm tilted Opus#2. That said, to me a touch of warmth is better with the IMR-R1 so I give the nod to the Opus#2 with this pairing. The QP2R does, however, provide a big, full concert hall sound.


Yikes, comparisons are super tough with the IMR-R1. Firstly, you have so many tuning options between the open/closed port and the array of filters. Secondly, they are at a price point new that I don’t have anything to compare and B-Stock it is one of the best IEM deals around and again I have almost nothing in this B-Stock price range.

I will provide a comparison between the DUNU DK-3001, which is a DD hybrid, and $500 and the FIBAE 2 at $560.

DUNU DK-3001 vs. IMR R1


This is an interesting head to head. I love most everything about the DUNU-DK3001 except for the medieval dungeon torture device style fit that the DUNU employs.

The sound of the DUNU is smoother in its delivery and no way near as in your face as the R1. Soundstage wise the R1 is certainly the king but the DK-3001 is no slouch, I find the R1 stage to be one of the best I have heard. I would like to say, in general, I really enjoyed the signature of the DUNU, I had no sound issues. I equally enjoy the R1 and I do feel it is a better IEM by a nose. Partly, because you have more tuning options and partly because it has a superb overall clarity. My critical points are more when I dissect the frequencies as opposed to what it brings to the table as one cohesive IEM.

The bass in both is incredible, with the R1 being a touch more present and snappy. They both deliver nice bass layering and clarity, Dunu is smoother and the R1 is crisper. The overall tone may be more natural with the DK-3001 and I prefer its tuning and tonality to the R1. I generally like a smoother tuning than an aggressive one. The R1 is extraordinary in its clarity and how it digs into the song and extracts the detail. Neither IEM are detail monsters and they confidently leave the analytical sound to others on the market. Treble is abrupt in the R1 and smooth in the DK-3001. I think by now you get the idea. Personally, you can’t go wrong with either, for me, I give the nod to the R1.



The soundstage is displayed differently between the two IEM’s, both are incredibly wide but the R1 has a more 3D geometry. The F2 is a fun, musical IEM with a warmish signature. The warmth of the F2 is so welcomed. The R1 is more detailed and direct with a higher level of clarity than the F2. The F2 adds a richer, lower mid-range with the R1 having more resolution and clarity in its mids. This showdown would more depend on the mood of the listener. As previously stated, I like smooth and warm. However, once you plug in the R1 and hear the bass snap and the how the sound all comes together you quickly become a believer.

Two different moods, but with the tuning options I would find myself grabbing the R1 more than the F2, even though the fit is better with the F2 and its warm tuning to make it a tough choice I would give a slight edge to the R1.

Sorry, there are not more comparisons I just could think of any fair comparisons that I have in my possession.

In Closing

IMR Acoustics is a new kid on the block, the owner is not. Bob has been the topic of drama from the Trinity days, but I can only speak from my own experience and it has been stellar. This is not an attempt to sway anyone’s thinking, it is merely my experience. Responsive responses, great service, quality first product, again overall stellar.

The ability to tune the sound to your liking is pretty incredible with the open/closed port dial and the tuning filters. Without a doubt, you can find something that strikes your fancy.

The build is an industrial inspiration and heavy duty but not uncomfortable in contrast to how it looks. I think they are built for the long haul and heavy duty.

The sound caught me by surprise. It kicks some serious butt! I know the overtone of this review appeared negative referencing bright and aggressive but everything comes together so darn well. The frequencies all blend and the sounds have an incredible synergy. There is oodles of clarity and resolution.

Bass is incredible, snappy, with little decay and it is always present. The bass never interferes with the other frequencies.

The cable really is not good. If I was asked to make one improvement, the cable is hands down the weakest part of this product. The sound quality of the cable is fine but the unwieldy ergonomics and the fact it doesn’t like to stay behind your ear makes it a challenge to like.

If you want validation for your purchase or a recommendation, consider this both. It is a terrific addition to the collection or if it is your only IEM, you can feel confident you have made the right choice. Enjoy!


Pros: Reference tuning
-Wide sountstage / frequency response
-Switchable open-close vent
-Exchangeable filters
Cons: Connectors are horizontally aligned
-Packaging doesn't look so premium
-Stock cables aren't compatible for other recessed 2 Pin IEMs


IMR Acoustics is a new in-ear brand around the block, founded by Bob who previously worked with Trinity Audio. So who is Bob? Before talking that, let me first give a brief insight about Trinity Audio. TA has been considered as one of the popular manufacturers for their active communication with the users and for their cost effective gears. Bob was the one who communicated with users and managed the entire making of their product. Now, as a guy who used to be a TA fanboy, I’ve tried almost all of their gears since their debut to Kickstarter with the Delta V-II. Few of their products felt to be somewhat like prototypes, but overall I had very good impressions with TA. End of last year, Bob got out from TA and started his own brand, IMR Acoustics.

Now before moving on, some of y’all may have heard about the complicated situations now going on with Trinity Audio. For those who do not know, I rather suggest you to search up what is going on with them, because it’s going to get way too lengthy to explain. Anyway, Bob have clarified that IMR Acoustics is clearly a distinctive brand departed from Trinity Audio, so I won’t be relating IMR much to TA here.

Enough with the background, let’s now move on to the IMR R1. IMR R1 is classified as a flagship IEM and currently priced for £500.00 (approx. $700). IMR R1 is their first model and they are preparing for other 2 IEMs – resulting into a lineup with total 3 products. Cheaper or pricier, that is unknown.



The R1 comes with a normally sized box and various accessories, including a 3.5mm cable, 2.5mm cable, 4 pairs of filters, AV adapter, 7 pairs of eartips, carrying case, and a shirt clip. It comes with most of the essential accessories and I’m quite satisfied about it. The packaging itself, though, seems to be somewhat simple. It didn’t particularly surprise me as I was aware as TA used to have a similar style of box.

But anyway, I’d still prefer the packaging to have a stylish look, or a similar approach to what Campfire Audio does. Their packaging is simple, yet beautiful. This is the first product from IMR, so I suppose this would get improved soon.



The earpieces are fully made out of metal coated with a color of gunmetal. I wasn’t able to find any flaws from its build quality and the earpieces seem to be pretty darn durable. The driver configuration is a hybrid 2DD, using a 13mm neodymium motors with a ceramic driver.

R1 isn’t only unique with its driver configuration, but also has a switchable open/close port. I haven’t not seen such feature from any other IEMs so far and caught my eyes right away when I first discovered the R1. The switchable port system that allows users to easily tweak the sound as well as the isolation. Sound leakage is moderate or relatively less than most ported IEMs, and it significantly improves when the ports are closed. There isn’t much change for isolation, only showing minimal difference. Though isolation is actually decent enough either way, so I don’t find this problematic at all. Difference does exist sound-wise, and I’ll talk about that below on the sound section.


Cable / Ergonomics

The stock cable feels smooth, chubby and has a sturdy feeling in terms of durability. It’s not particularly thick or stiff, so it won’t be problematic while you walk around with these. The cable has a comfortable fit and doesn’t occur microphonics. One thing that I’d like to see a change though, is its connector alignment. It uses a normal ciem 2-Pin (0.78mm) connectors, however the connectors are aligned horizontally, not vertically like most IEMs. This doesn’t mean that your ciem 2-Pin cables won’t fit but you have to re-shape the earguide, if the cable has one, and the process gets even longer if the earguide is shaped only with shrink tubes without the steel wire.


Usability / Matching

The fitting is pretty nice. It’s ergonomic and comfortable even after long time listening sessions. It’s meant to be worn over-ear, so wearing these straight down won’t give you the best experience. Keep that in mind if you prefer wearing earphones straight down.

IMR R1 shows adequate, but distinctive sensitivity to different filters, players, cables, and eartips- not extreme though. In this review, I’ve used JVC Spiral Dots eartips (as I believe it performs the best with these) and the stock cable. Aftermarket cables could surely bring out more from the R1, but the stock cable does its job. At least this cable doesn’t feel like holding back R1’s potentials. I have used the black default filter and paired with my QP2R and DX80.



R1 does an awesome job presenting weight and depth of the bass without getting muddy or loosened up. It is impressive how clear and prominent the bass sounds without overwhelming the upper frequencies. There’s a bit more bass amount than typical slightly-V shaped but less than Shure SE846 or Campfire Vega. The edges of the bass are polished, giving a smooth, analogue taste. Now most flagship IEMs that are well known for its bass performance are usually equipped with large amount of bass. R1 manages to keep up with such IEMs, picking up all the details to the very low notes, however with just the right amount of bass.

Don’t get me wrong, the amount is plentiful and has a strong and manly rumble to the lows; it just doesn’t get the point where it feels stuffy. I’m quite positive bassheads could also find R1 to be satisfying. What I also love from the bass is its wideness. It spreads out wide without the border (or the edge) of the bass getting vague, making bass more prominent and full-bodied. It also got great density with that DD-style punch at the lows.



Sweet, creamy mids are slightly stepped ahead with a natural thickness. The vocal sounds lively and airy, providing a very spatial presentation which I found to be quite unique. R1 does well on both male & female vocals, and I’d say it has that “Multi driver-like” richness but with better coherency. The overall brightness is just about neutral, however the ceramic driver adds a brighter tone to the upper mids, making the female vocals more refreshing. The sibilance section from the frequency is briefly polished, making it non-fatiguing. Overall, R1's sound signature reminds me of HYLA CE-5 but with a more naturally toned mid range.


Highs, etc.

It’s easy to think for dynamic drivers to sound dull on the trebles, but thanks to the ceramic driver R1 manages to pick up the details with good precision. Highs feel clear, crispy, and does well on expressing the dense texture from treble instruments. It’s visibly brighter than lows or mids, however it won’t be a problem as it doesn’t get spiky. The highs on the R1 tends to stay transparent without any coloring added to it. The treble spreads wide sideways as the bass did. And with the spatial mids added to that, IMR R1 generates one of the finest, largest headroom for an in-ear.



IMR wasn’t trying add unique coloring on the R1, but they rather stuck with the basics and nailed it. IMR R1 aims to have maximum wideness for both frequency response / staging, and I'd say they accomplished it very nicely. I can consider R1 to possibly have one of the widest soundstage among flagship IEMs available to the market, and that’s a good start for IMR. I’ll be glad to keep my eyes on how IMR shapes out their products in the future.

Thanks for reading! Visit for more reviews.​

Thanks to IMR Acoustics for providing the R1 in exchange of an honest impression.
I am not affiliated with IMR and none of my words were modded or asked to be changed.
I have nothing but good things to say about Bob. All of my transactions with Trinity were delivered accurately and in a timely fashion. Any correspondence was handled professionally by Bob. The R1 is out of my price at the moment. I would quite interested in a "budget" line, if Bob goes down that route.
"It’s visibly brighter than lows or mids". What are bright lows?
Watermelon Boi
Watermelon Boi
@MrDelicious Just highlighting that trebles are clearly brighter.
Pros: great adjustable sound, detailed sound, wide sound stage.
Cons: need custom tips as they are too heavy for normal tips.
hi all i have now had these for a few months.

i work in coffee shops a lot so need good noise isolation, i got a good fit with foam tips but when they got hot the kept falling out.

i was struggling to get the best sound with the supplied tips and was going to give them back but i asked on here about custom tips and Blommen said that i can get them from I live in London and used Gisele at for the moulds. she was really helpful.

they cost £50 for the moulds and £55 for the tips.

Now that i have the custom tips, it changes everything !!!!!!. it took me a wile to get them in ok. they are amazing, they never come lose, the base is now so full with the copper filters, altho i am going to try the blacks again :) they sound great. i can sit in a cafe at half volume, and not hear anything :)

i would advise everyone to get custom tips for any earphone, definitely the way forward.

UPDATE tried the black and sticking to the copper :) re listened to all my music, they sound unbelievable !!!!!


Pros: Customizable Sound, Full-Metal Construction, Excellent reliability, Filters and Vent settings, High-quality cable, 2-pin connectors, Excellent bass and treble, Good Impact, Nice PRaT, Engaging Sound, Revealing signautre, Good all-arounders
Cons: Pretty Pricey, Premium Quality comes at a price.
IMR Acoustics R1 - Customizable Enjoyment

IMR acoustics is one heck of a little IEM that comes with tunable sound with both filters and an option to change its design from closed to open. We'll look into what it does best and what its downsides are today.


We haven't had the chance to review any IEM from IMR acoustics before, and we aren't sure if there's been any, but the creator of IMR acoustics is a respected engineer who has vast experience with designing and tuning IEMs, so he had an excellent base start for IMR R1. As the company is new, we don't have a large amount of data regarding its customer interaction, but our preliminary data shows that IMR acoustics is from UK and will be very helpful with your purchase decision and will provide high-quality after-purchase assistance.

It should be noted that I have absolutely no affiliation with IMR Acoustics, I am not receiving any incentive for this review or to sweeten things out. This review is not sponsored nor has been paid for by IMR Acoustics or anyone else. I'd like to thank IMR Acoustics for providing the sample for this review. The sample was provided along with IMR Acoustics request for an honest and unbiased review. This review will be as objective as it is humanly possible, and it reflects my personal experience with IMR Acoustics R1. Every opinion expressed is mine and I stand by it, the purpose of this review is to help those interested in IMR Acoustics R1 find their next music companion.


Purchase link:

Purchase link 2:


About me


First things first, let's get the packaging out of the way:

IMR R1 comes packaged in a high quality, pretty weighty cardboard box. It is fun to open the package, and IMR Acoustics placed a good amount of care into designing an excellent first interaction between the customer and R1.

The outer package is black and it has a very sleek large logo on the front, which slightly reminds us of a sci-fi movie. On the back of the main package, you can find the main specifications for IMR R1, which are quite impressive as well, as it features a 13mm Dynamic Driver along with a ceramic BA driver.

The box within is used to store the R1, and it is red in color. All materials used are thick cardboard and they all provide an excellent amount of protection for R1.

Inside the main box you can find R1 seated in a foam cutout, without their cables attached. After removing the first layer of foam cutout, you can discover the rest of the accessories sitting comfortably just below. There is a professional cable, with what seems to be high-quality connectors, placed inside a small hard carrying case that also wears the logo for IMR Acoustics. We noticed a sufficient collection of tips, and although IMR R1 doesn't feature our favorite tips, Spinfit, they do feature a few high-quality tips which offered us a very efficient and pleasurable usage.

Box contents:
- The IEM Body
- 1.4m cables
- Hard Transport Case
- 6.3mm Adapter
- Tip Selection
- 5 Audio Filters
- Filter Holder

All in all, the box contents are good for their price and usage, there aren't any accessories we really found missing from the package, unless you want to count Spinfit tips, which would be the best selection of tips for a IEM.

What to look in when purchasing a high-end In-Ear Monitor

Technical Specifications

13mm driver featuring Neodymium motors with beryllium diaphragm + Ceramic driver
IMR Open and close porting system
5 Audio filters
2 Pin detachable cable
Impedance: 32 Ohm
Sensitivity: 108 +/- 3DB
Frequency response: 14 - 40000Hz
24ct Gold plated 3.5mm Jack

Build Quality/Aesthetics/Fit/Comfort

Get ready for the little trip!

Starting with the build quality, IMR R1 is made out of very high quality metals, and this makes them ever so slightly heavier than similarly sized IEMs. The plate on which the filters rest is also made out of a large piece of metal, machined with care, and the filters are made of metal, some of them with material inserts for the best acoustic dampening.

The IEM bodies seem to be carefully machined, and while the IEM bodies are larger than what we've seen to date in most cases, they surely look sleek and sturdy. There are actual screws placed on the IEM body, and while we didn't open the IEM body itself, we're sure that IMR acoustics made those to be easily serviceable, so they can provide a large number of years of flawless usage to the one purchasing one. There is a Open/Closed dial on the back of the IEM body, which, when moved, will provide a more open or a more closed sonic character. The Open position will give the sound more soundstage in size, but it will also increase the bass resonance, similar to the mechanism we've noticed in Sennheiser IE80.

There are also a set of interchangeable filters included with IMR R1, each with a sound signature of its own. The sonic changes are not exactly small, but they are not as high as going from a different IEM to R1. Each Filter is made of metal and is connected to the IEM body with a metallic thread (screwed). The whole thing is made of metal and feels extremely solid, we can't detect any plastic in the build of the IEM bodies, and we're quite enthused with the findings so far.

The cables are connected to the IEM body via one of the most loved connectors, which is 2-pin. The cables are quite thick, and they seem to hold an excellent overall build quality and thickness.

The cables also have metal insertions, and albeit we feel like it might be overdoing it a little, it does provide a sense of well-made and high-quality.

The 3.5mm TRRS jack is angled and gold plated.

We're crazy for the build quality of R1. When it comes to their comfort, they are on the larger side of things, being a rather large IEM, with large IEM bodies, a normal to larger bore and over-the ear wearing style. The overall comfort is good, but those will not disappear in your ears, and the metallic materials included in the build should be considered for comfort reasons. The tips included provide excellent comfort and wearing, they do not get slippery with usage, and R1 can be used for very long periods of time with literally no fatigue.

When it comes to their style, they are on the slightly industrial side of things, with a larger wheel on the back, a larger physical size, and with screws included in the build.

All in all, we are amazed by the build quality of R1, and we feel those are IEMs that can last you for a lifetime, we like their comfort, and we feel that their aesthetic style will fit just fine with many customers. Of course, the fun part will be the sound.

Sound Quality

IMR R1 is the type of IEM that makes you think "Now here's a warm IEM with a really engaging signature!"

In a few words, they are warm, with a strong sub-bass and mid-bass, they bear an excellent midrange that is very vivid, energetic and very detailed. The treble is engaging and energetic, with a good amount of sparkle and with the area after 10kHz smoothing out a bit, but staying fairly present and energetic.

The sub-bass is one of the most interesting aspects. Along with the mid-bass, the sub-bass of R1 can change when you use the wheel on the back of the IEM, as the IEM features a closeable acoustic chamber. This compresses the bass for quicker, less in amount and more precise response in the "closed" position, and a slower, more natural and much bigger in amount response with the wheel positioned in the "open" position. The trick here is that you can fine tune the IEMs to your tastes, and you can go anywhere from really bassy to pretty tight and quick bass response. Anything in between is doable and R1 is here to bring that to you.

The midrange is one of the most vivid, energetic and detailed we've seen on a IEM in the 500£ area. It can render male and female voices with excellent depth and emotion, it can show a juicy guitar solo in the songs of Metallica, and it can make you cry when you listen to the sad songs of George Enescu in classical music. In fact, the key word here is their versatility, R1 sounds good with classical, R1 sounds amazing with pop and electronic, and R1 sounds bloody sweet with metal music. There's no genera they really lack in, and if you require one IEM to do all musical styles, R1 and its sweet midrange sure can do any music genre you throw at it.

The textures of R1 work well with the textures of a violin, the textures of a guitar, and they seem natural and feel just right even with both male and female voices.

The treble is sparkly, it is firey and it becomes smoother as it goes higher. There's no serious roll-off to be discovered, but the treble climbs nicely with strength and expression / emotion until the 8-9 kHz area, after which it becomes slightly softer, all whilst keeping an excellent amount of air and separation between the instruments, defining an interesting stage and a good amount of high-end details.

All in all, the overall signature is very versatile, it simply works well with almost any music style you like to listen to, there's nothing R1 doesn't do well, and if we are to pick something that they do best, we'd say that they do similarly well in everything. Vivid, detailed, energetic, forward, and well-textured are just a few of the words we'd use to describe the sweet sound of R1.

A lot of those descriptions apply to R1 regardless of the filter they are used with, but some of the filters can change the sound to the point where those descriptions might not be accurate. We've tried using the filters that seemed the most natural and reference via IMR Acoustics description. We tried Black, Pink and Blue filters to provide the review for the Sound Quality part.


The soundstage of R1 is variable in its way, every filter and the wheel on the back also changing the soundstage size and type R1 has. There's some instrument separation lack in certain combinations, but if you like your music blended together rather than well-separated, then R1 sure is one of the best IEMs to do that, along with providing a large soundstage, provided you select the right combination of tips, filters and vent position. In all honesty, we could get to sound well-separated, wide, and even narrow if we wanted to, it is a really interesting thing to have and play with.


The ADSR and PRaT (Texturization) of the sound stays fairly consistent across all filters used, but it changes with the position of the vent. Things are best defined and clearest with the vent in "closed" position, and using it in "open" position will slowly make the transients go from good to rather natural all the way to rather slow. In all fairness, the texture definition is still rather good with the vent in fully open position, but compared to it in closed position, it tends to render textures less enhanced and smoothed out. For Jazz we strongly recommend the vent to be kept in open position, while for EDM / Electronic music in the "closed" position. Other musical styles can be experimented with, but those would be our picks so far.

Portable Usage

When it comes to their portable usage, we were quite impressed with R1 and their portable usage. They are actually very svelt and their cables never gets in the way of listening to music. Even if it doesn't fully work for you, you can happily change the cable with any of the 2-pin connector cables that can be bought from a third party seller.

When it comes to their isolation from the outside noise, it is extremely good, you are separated from the outside noise, and even while gaming, it is impossible to find the noise of our workstation, even at full load, if there is a little music playing. Taking a walk through the noisy streets of Bucharest is no issue for R1, as it separates the listener from the environment, and on this note, please pay attention while walking with music!

There is no microphonic noise that we can detect while wearing R1.

R1 can safely be driven from a smartphone, and provide excellent results, but we'd recommend using a stronger source so you take full advantage of this amazing IEM.

There are many sources that can really drive them, but the best results will be the best with a high-end source like Opus #2, DX200 and FiiO X7mkii/FiiO Q5.


IMR R1 vs Dunu DK-3001 - This is probably the most interesting comparison given their price and overall build quality, as both are really solid IEMs, made really well by good companies. DK-3001 is slightly larger, and it comes with Spinfit tips, which is a plus, but their shape, especially the inner part of it, is slightly less ergonomic for some folks, where R1 doesn't come with spinfit tips, but it is very ergonomic for most ears, although they are slightly large. The sonic abilities are outstanding on both, and the overall detail retrieval and overall sonic quality is similar for the two, although R1 has the upper hand in customizability, and although it reveals the same details as DK-3001, R1 is fully customizable and can change with the taste of the listener until it can fit almost any bill. By default and with most filter combinations, R1 is warmer and provides a slightly thicker sound, but this shouldn't turn anyone away from them, as they are quite good like this. It doesn't quite take the place of DK-3001 in terms of everything else, especially soundstage size, where DK-3001 tends to extend more, but it has its place as a competitor for DK-3001 in this price area.

IMR R1 vs Sennheiser IE800 - IE800 is quite a bit more expensive than R1, and they are slightly more revealing, but they make a fair competition given that IE800 has been slowly growing less expensive, with the release of IE800S. Now that both can be found more or less at the same price, they should both be considered by a buyer. Starting with the build quality, no one can fault Sennheiser or IMR Acoustics, both standing on similar grounds, but R1 has detachable cables straight from the base of the IEM, while IE800's cable cannot be detached from any other point than from below the Y split. The size of Ie800 is smaller, but R1 manages to win our hearts in ergonomics because the tips of IE800 still get slippery after a while and need to be taken out and washed when they get, while with R1 we haven't noticed this. The sonics are quite different, IE800 being strongly U-shaped in its sound, with a very thick, enhanced and extremely satisfying bass that is sure to please any rock / metal / pop / acoustic music listener, while R1 doesn't get quite this strong in the bass with any combination of filters and vent position. The midrange is actually more revealing and has more detail with IE800, but it is more forward with R1, thing which means R1 works better with Jazz, Vocal and other voice-oriented music where the midrange needs to be presented forward. The treble is considerably more forward on IE800, having more sparkle, more shimmer, more impact and more extension, but those all come at the price of very easily sibilance reveal, meaning that IE800 will show sibilance extremely easily, and if your music was sibilant, IE800 will show that, IE800 being not recommended with music that needs to be laid-back and relaxing, and being much better in electronic, pop, rock, metal, where laid-back music works better with R1, like downtempo, Jazz, and other types of music that need to be played in a laid-back and relaxing fashion. On this note, R1 still is extremely versatile.

IMR R1 vs Beyerdynamic Xelento - Xelento is another interesting IEM to compare to IMR R1, as the price of the two can be close, and because one might be considering both. On the outside, the aesthetics are in favor of Xelento as they have a sleek and rounded body vs the similarly shiny, but featuring-screws body of R1. On the comfort part, R1 can be slightly more comfortable, especially as it has a more universally sized bore size and it will work with Spinfit tips and other third party tips. The sound is vastly different, with Xelento being much bassier, much thicker, much more focused on the bass and midrange, where R1 feels more balanced over the whole spectrum. Here, R1 works better with Rock, Metal and Pop / EDM, where Xelento is much better with Jazz, Classical, Downtempo and other laid-back music types, or for those who want their music to sound laid-back. There is a good sense of space and instrument separation in both, but the treble of R1 feels more natural, compared to the overly smooth and friendly treble of Xelento. Of course, for those looking for the ultimate forgiving IEM, Xelento is quite forgiving, being good at letting the music shine with albums that have large amounts of sibilance and such. The two IEMs feel like they are geared towards different types of customers, R1 being quite good for those who want a versatile and customizable IEM, which sounds mostly balanced with a warmer sound, while Xelento is geared towards those who are looking for the ultimate relaxation and ultimate music experience with a smooth sound.

Recommended Pairings

IMR R1 seems to respond very well to being paired with a higher quality source, like iBasso DX200 or FiiO X7mkii. While it works with smartphones, those don't reveal the full amazing sonic performance of IMR R1.

IMR R1 + iBasso DX200 (AMP5) - Combining IMR R1 with a true high-end DAP like DX200 paired with its AMP5 module sure is a blast as DX200 offers one of the best sonic performances there are. The transients and detail revealing abilities of R1 are instantly improved when compared to them being driven from a smartphone, and there is an excellent sense of depth and width to all music played through the combo. Everything is placed where it should be, the music feels emotional and enthusiastic, and we can safely say that this combo will be a favorite for almost anyone who wants the ultimate experience from their IMR R1.

IMR R1 + FiiO X7mkii (AMP5) - FiiO created something very competitive in their X7mkii, and it is really close to DX200 with its AMP5, sometimes comparable, depending on the IEM or Headphone. As AMP5 for X7mkii makes things much better for this little DAP, we surely recommend our fans and readers to look into this specific combination for the best results. X7mkii with AMP5 provides an excellent depth and width to music, a ferocious impact and dynamics, that not to be taken lightly. Transients offer music a better texturization and everything feels snappier when compared to less expensive sources. The power and abilities of X7mkii are quite similar to those of FiiO Q5, and if both are running the same AMP module, we feel that one would be really happy with either.

IMR R1 + Hiby R6 - Here, R6 is a little on the thicker, warmer and less detailed side, when compared to X7mkii or DX200, but it is much better than any smartphone we could find to pair with R1. The transient reproduction and dynamics from R6 to R1 are quite incredible. The highlight of using Hiby R6 is how fluent its whole firmware is, being a true pleasure to use and experience. We felt, however, that we could name this combo R7, in light of the names of both devices.

Value and Conclusion

IMR R1 is a new thing for us, coming with adjustable and configurable sound, and with an impressive performance, form a company that we don't know quite that much about. We did our investigations, and it seems that the director of IMR Acoustics is an outstanding acoustic engineer named Bob who was previously involved in many successful projects.

With R1, there are many things to love about it. First, they have a really good build quality. It is rare that we see a IEM assembled using actual screws or including actual metals in its build. While it isn't quite that light, it sure isn't heavy for the quality of the materials used.

IMR Acoustics made sure to also use some of the highest quality cables we've seen to date, and while this seems to still be a rarity, R1 comes with detachable cables, and even with 2-pin based connectors, thing which is rare, but well respected as 2-pin connectors provide one of the highest quality connectors there are.

The aestetics are good, IMR R1 looks like an excellent IEM to take with you regardless of your personal style, and they'll surely fit with almost any environment you're in, but they really shine when it comes to looking slightly aggressive and slightly industrial. The comfort, on the other hand, is quite good. We found excellent comfort in them although they are on the slightly larger size.

The sound, the most important aspect of any high-quality audio purchase, is quite outstanding. The removable filter design found on IMR R1 is not only well-made but also works very well. We're really happy that IMR Acoustic included a large number of filters in their package, along with a really well-thought venting mechanism that lets you really customize the sound. From brighter to warmer signatures, from relaxed to tight and energetic signatures, IMR R1 can do a lot more if you take the time to tinker with them. Their detail retrieval is very good for the money, and at 500£ they surely are a nice deal, as you're getting an entire package of signatures.

If you're looking for something really interesting, comfy and well-made, we urge you to check out IMR Acoustics R1 as those are some of the most impressive IEMs we've seen at 500£, especially in build quality and customizability options.

Stay safe and remember to always have fun while listening to music!



Contact us!

(Click Buttons)




Pros: Delicious dynamic bass
Customization to fit your preferences
Soundstage width and depth
Solid construction (time will tell)
Price to performance ratio is very good
Cons: Cable is a mess design-wise
Treble can be sharp at times
The IMR-R1

About me

So first of all, a little backround on me. I am not a reviewer, nor do I have any aspirations on being one. I simply write this review to highlight this product because I think it deserves attention and also because it is a way of giving back to the community. I am more of a silent on-looker than a participator in forums, partly because of me browsing on mobile which makes it tedious to write long messages and partly because I am a man of few words. A habit I now break.

In my opinion, a great number of audio equipment reviews get caught up in flowery poetry in order to describe sound. This makes every iem/headphone sound great in some way and becomes an affirmation of a product the reader already owns or is set on owning.
On the other hand, you have those that seem to be an unboxing with a side-order of "It sounds good out of my phone and the soundstage was wider on my amp, all in all it's great!"
My intention will be to try and hit a middle ground: It's a product (objective), yet it reproduces art (subjective). Let's hope I succeed.

In order to read this review, you need to understand that I am not objective as far as sound goes, not in the least. Math and science is objective but "I am not a number, I am a free man!" So, my preferences will shape my opinions, and here they are: I listen to metal 80% of the time, 10% old progressive rock (Rush, Pink Floyd, Yes tec.) and the rest is a mix of reggae, female vocals and electronic. I listen at semi-loud levels and I prefer warm sounding gear with big bass, mids must be present for guitar and vocals and I like my highs to be airy and a bit recessed or at least without any harshness or peaks.
There, I just described my ideal iem. You needed to know, otherwise the review would have no context. So, with that in mind, let's at long last get to the review...

It's....a box!

IMR R1 -Overview

The IMR-R1 is a creation of Bob, formerly of Trinity Audio. There has been some controversy surrounding his former place of work, but this has nothing to do with his new firm. Also, I don't own any TA iems so I'd rather not get into it or comment on it.
This is supposed to be the iem he "always wanted to make". Releasing at 500£, the equivalent of 710$ for those over the pond, it is firmly taking a place in the mid-tier category price wise. I however, paid 300£/450$ for a B-stock. I will get into the differences later but let us have look at the specs first:

  • 13mm driver featuring Neodymium motors with beryllium diaphragm + Ceramic driver
  • IMR Open and close porting system
  • 5 Audio filters
  • 2 Pin detachable cables (3.5mm TRS and 2.5mm TRRS balanced) Impedance: 32 Ohm
  • Sensitivity: 108 +/- 3DB
  • Frequency response: 14 - 40000Hz
  • 24ct Gold plated 3.5mm Jack
  • 1.4M length OFC cable
  • Hard Case
  • 6.5mm Adapter
  • Huge selection of ear tips for the perfect fit
This is what is included in the B-stock package

As you can see it is a pretty significant package, well designed box yada yada, everything is good and feels like a premium product. As I said before I have a B-stock, which means that I don't get a balanced cable and that there might be some minor imperfections. Luckily, I have found none.
Five different filters and the option to close/open the port for more air gives one great customizability as to the sound that suits your individual tastes. The filters have each been tuned for a specific sound-signature but to be perfectly blunt: no point in getting an iem with dynamic drivers unless you plan on getting your bass on! And fret not; these can seriously kick!

Now I will primarily be focusing on the bassier two filters, the Black (standard) and the Copper (moar bass). I will not go through all five filters because this review would be too damn long! All listening is done on Sony WM1Z and Samsung Note 8 single ended unless otherwise stated.


Let's get the cable out of the way first, this is a weird one.
The quality of the cable is good, thick enough so that it shouldn't fail in the near future and when/if it does, it is replaceable. I had a little bit of difficulty with the left part of it because it wouldn't stay behind my ear. It seems to have to have sorted itself out now, so not a problem anymore.

What makes it a weird one is the connections on the earpieces. What the hell is going on here? You pull em out and think "ah, standard 2-pin connection" but no! Upon closer inspection there are several factors that make these a PITA and the worst part is, it could have been avoided so easily. The female end on the earpiece is turned around 90 degrees, which means that the pins on the cable have to line up horizontally instead of vertically as in EVERY OTHER IEM!!! Why?!? No, seriously why? What this means is that if you have a cable or buy a cable you must make sure that it does NOT have ear hooks or is shaped in any ordinary way. Also, connectors must NOT be angled. This is of course not a problem if you just stick to the standard cable in the bundle. Luckily the sound makes up for these shortcomings.

Up close with my custom tips, these are NOT included:)


Mmmmm dynamic bass. These are the epitome of dynamic drivers bass wise. They kick with such authority that you unconsciously draw your lips back in a smile, showing of your rattling teeth to anybody looking. First off, these go low, 30-50hz is nicely heard and felt. The rumble is heavenly and just lies in the background of the track if it is mastered to include it, giving the music a nice warm foundation to build upon. From there, 60-100 is the main emphasis with the two filters I use and let me tell you: feels great! The impact is felt, and it gives life to rock and metal, just makes it sound like you are listening to the band live or on speakers. The drums sound like wardrums and just makes you nod your head while the bass guitar around 100hz and onwards pounds away just reorganizing the insides of your skull. Now granted, all this sounds like they are in severe basshead category...and they are, bass is definitely enhanced with the black and copper filters. The thing is though, in my opinion the bass is tight and non-intrusive (black filter) to the midrange. It does color the sound though, this is a warm iem. Warm yes, but not veiled or dark.

With the copper filter it does get a little dark, I wouldn't exactly say veiled but warmer and darker. Also, bass is less impactful and more analog sounding, a bit looser and midbass focused.

Tl;dr Exceptional


Now with all that bass talk you would think that the mids would be taking refuge behind it and that the IMR-R1 is yet another V-shaped pretender. Not so. With the black filters this iem is a kind of W-shaped signature meaning there is an equal distribution across the frequencies without it being balanced or reference. That being said, bass is still the frequency that has most quality and quantity, however it does not mask the mids. The mids are still very present and clear, actually surprisingly so. Clear as a winters day with the sun shining, the bass ads a hint of warmth to the mids but does no veil them.

Guitars are exceptionally crunchy, adding great life to all kinds of rock. Horn instruments also sound amazing. Vocals come through with good detail, better than average but there is nothing romantic about them. I cannot discern any difference quality-wise between male and female vocals. They do have a decent amount of air to them. The most exceptional part of the mids for me personally is this: even eq'ed, sub-bass and midbass up 30hz + 4.5 dB / 62hz +3 dB / 125hz +1 dB the mids come through clear and detailed without any lack of details. And without the drivers sounding "stressed" or strained. What I can't figure out is if this is the mids doing a good job or the bass? Either way it doesn't really matter; great stuff!

Tl;dr Very Good


Alright, so the highs are the weakest part of this iem –at least with the filters I prefer. I am not sure why dynamic drivers that have a great quantity of bass, usually have a hard time with treble. I have noticed this with the CA Vega as well, it seems in order to have a single dd deliver hard hitting bass the treble also becomes hard hitting, which is not what most people, myself included, prefer.

The highs have a good presence here, they do a fine job of letting themselves be heard through the rest of the sound spectrum. Even in complex passages they are not masked by bass or mids, but the detail is simply not there. There is, to my ears, a greater emphasis on lower treble, -cymbals crash with authority and provide awesome energy. When moving up the ladder frequency–wise the treble lacks air and extension with the black and copper filters, with the copper filter the treble becomes significantly softer and easier on the ears. Even so, the treble is not fatiguing to my ears when driven by the WM1Z, but on my phone the treble can be a bit tizzy (tst tst) with some harshness. This is with the black filters, I have not gone through all five on the phone, so experimentation can be done but, in my opinion trebleheads should look elsewhere.

Tl;dr Good

Great synergy, from single ended no less!


As with other aspects of the IMR-R1 the soundstage is highly customizable. On the back of the two earpieces is a wheel that can be turned towards "O" or "C" as in open or closed. I have found that a ¼ of a turn is the sweet spot for me, sometimes a bit more towards open. This widens the soundstage, giving more air to the whole presentation. Also taking away some harshness from the treble and extension improves. With bass as well, more extension but in turn it does not hit as hard.

It is hard to describe the soundstage when so many factors affect it (filters, the wheel, tips, cable) but generally, with my custom ear tips, original cable and single ended, the soundstage is deeper than it is wide although width is decent. If you put your fingers lightly on the ports on the back, covering them up and then taking them away you can clearly hear how the soundscape spreads out from the box-sized in your face dimensions, into a clearly better separation of instruments and a wider presentation.
How much you turn the wheel obviously affects isolation from the outside, so again it is crucial to find one own's sweet spot.

Tl;dr Very Good

The most neutral and organic sounding filter.


Before we reach the end of the review I would like to throw in some short comparisons, the keyword here being short. It is important to note that these comparisons are a bit unfair as I cannot listen to R1 is balanced which makes them less valid than I would like. Thanks, weird cable connectors!

CA Vega

Compared to the Campfire Audio Vega, the IMR R1 is somewhat similar in many regards. Both sport a metal housing with an industrial design. The R1 is in my opinion hampered looks-wise by the customizability factor and the Vega wins here, by have having a cleaner design. Fit wise it is a toss-up. I had my custom tips made for the Vega (thanks Custom Art) and now use 'em on the R1 so yeah, fit is too personal to rate. Quality also seems about equal.

Sound: compared to the Vega the R1 has greater quantity of bass (black filter) and I want to say better quality as well. Hits harder because it has a bit more midbass and has greater potential for eq, maybe because of the size difference (13mm vs. 9mm). This in turn makes the R1 warmer than the Vega. Mids are better on the R1, I found the Vega to be harsh in the upper mids making female vocals sound strained and adding sibilance to some records. Details seem equal. Treble is similar in tonality, but Vega has the better extension. Soundstage wise the Vega has better separation and depth but not as wide.

ASG 2.5

Oldie but goodie. These two iems are actually nothing alike, apart from them being considered bass monsters. My ASGs are custom; so fit, build and so on are not comparable.

Sound: Bass on the R1 hits harder, cleaner and deeper. The 2.5 has a lot more midbass and it colors the whole presentation, making it warmer and more mellow. Mids on the 2.5 are veiled and lack detail comparably, a lot more recessed. The treble is more present on the R1, sharper and less airy. The 2.5 has a softer and more extended treble, though you have to look for it as it is not "in your face". Soundstage goes to the 2.5, it is simply outstanding, more like a headphone than an iem, very holographic. Weird, given the bump in midbass but there you go.

These really pound at your eardrums when listenig to metal!


As you can tell, I am pretty stoked about the IMR-R1. This is not the most natural or realistic iem out there. However, it does a great job at presenting music in a fashion that I find entertaining and moving. There is no doubt in my mind that if you are looking for a capable universal iem with an ability to rock your socks off, you should look no further. It might not be sophisticated or a reference monitor, but I'll be damned if it doesn't make me smile and enjoy my music to an extend that I have not experienced in a very long time.
Pros: Fun, Impactful, Detailed, Filters work
Cons: Don't scream high end on the outside, a bit of driver flex
Firstly I would like to thank Daniel for passing this sample on to me for review, the sample came from IMR themselves. They have received well over 50hrs of burn-in as is suggested.

*disclaimer: This sample was provided for the purpose of writing a review, no incentive was given to write a favourable review. All opinions expressed are my own subjective findings.

Gear Used: Audio Opus #2 / iBasso DX200 > R1


Packaging, Build Quality and Accessories:
The R1 come in a simple box, it is black and red with the company name on the front. I have been told the packaging may change in the future, but as is it is a fairly standard affair with specifications listed on the back. Slide the outer sleeve off and you will find the R1 held tightly in place in a foam insert, the carry case is held in a similar fashion as are all the rest of the accessories. For the price the packaging is not luxurious, but it is compact and serves its purpose.

The R1 are well built, the housings are metal and well finished with a 2-pin detachable cable. The cable socket is mounted horizontally instead of vertically like most IEM's, so cables with a moulded ear hook will not fit very well. The dials to change between open and closed vents on the back move fairly easily, they could be a little tighter to avoid accidental adjustment upon insertion. The cable is rubbery with good strain relief, out of the box it takes a little time for the cable to keep its shape behind your ear, but it's not a big issue. The nozzle filters have a good size thread and screw in tightly, it is well implemented. The different shades of metal of the housing don't scream high-end, but overall they feel like they will last a while.

Accessory wise you get the filters which are screwed into a block of aluminium, a 3.5 to 6.3mm adaptor, a semi hardshell carry case, 2 cables (one 3.5mm, one 2.5mm balanced), regular single flange tips in S, M and L, a pair of M bi-flange tips, and 2 pairs of foam tips S, L. Overall you get a fair amount of accessories, and I can't think of anything else that could be included.


Comfort, Isolation and Driver Flex:
The R1 are an odd shape, but once you find the right tip they are comfortable over longer periods of time. the housings are metal so a little heavier than most standard IEM's, however I don't find them falling out of my ears, the cable is soft enough to not be a problem during use.

Isolation is good, both with the vents open and close the isolation is roughly the same in my opinion. They drown out a fair amount of outside noise, and would be fine for day to day use, but not the best in noisy environments.
Driver flex is sometimes an issue, I found it more of an issue with some tips over other, so be sure to experiment. The driver flex is quite bad, but tends to only present itself upon initial insertion.


Now these come with various filters, so I'll write a little summary on each filter. They also have the open/closed vent option, however I did not find this to make a huge difference so I left them open (closed has slightly bigger mid-bass impact, open offers a slightly wider soundstage).

Black (stock):
The black filters give these a fun but slightly L-shaped sound signature, the bass is big and full bodied, with incredible sub-bass presence. The midrange is pushed back somewhat, and does not allow the finer details of recordings to shine through properly. The highs are not exactly recessed, but they are controlled and never overly bright or in your face. The lows carry real power with these, feeling the impact along with hearing it, the midrange lacks a little definition with the black filters and the highs ultimately lack a little air and separation up top. The black filters are great for those looking for an engaging, powerful and fun sound signature and these sound very good with the black filters. Micro detail retrieval is good but these are more about having fun and letting go of technicalities and just enjoying the sound, and that they do very well with excellent extension on each end and great coherency.

With the pink filters, the bass is a little more controlled than the black, having a little less body and quantity. The lows still extend well into the sub-bass but kicks are a little more subdued, and they are not as lively and as fun. With the pink filters, the mids gain little clarity and sound a little less full, but the highs are still lacking a little air and openness that leads the pink filters to sound a little odd. There is a narrow band in the midrange that is more prominent than the rest of the sound, by controlling the bass, the midrange is a little cleaner but the balance of the sound is all off and overall I don't like this tuning as much.

Bass, Bass and more bass, these are the ones for the real bass heads out there. They offer plenty of punch and articulation but the lows mask the rest of the sound, making them sound a little muddy overall. Again I am impressed by the power down low, and female vocals still come across with fairly good presence but the lower midrange is masked and the highs are rolled off. The sound is very smooth with these filters, but again way too much bass for most people.


The lows are much more balanced here, the upper midrange seems a little forward with these filters. These is still excellent extension down low but the lows are much more controlled, this allows the midrange to shine through. The midrange has great clarity and detail retrieval with the orange filters, the bass no longer comes in and overpowers them. The tonality of the midrange is erring on the colder/analytical side of sound, but they never become harsh or fatiguing. The highs are lightly rolled off, this leads to a fatigue free listen, but one that has a slight focus on the midrange. Overall the orange filters sound very good, with a slightly mid-forward sound but one that still has excellent extension down low just with a bit more control, and lightly rolled off highs.

Now these hit the spot in terms of balanced sound without anything sticking out too much or being too emphasized. There is excellent clarity across the board with the blue filters, there is no real mid-bass hump like with a few of the other filters, but there is still fairly strong sub-bass presence. The lower midrange is no longer shadowed by the lows, the highs are present and extend with ease and they sound quite coherent and natural. The sound is still powerful and engaging, and not a laid back and smooth sound. The blue filters to my ears allow the most detail to come through and there are plenty of moments where you hear subtle details in the recording with these.

With open vents the soundstage is fairly wide, and there is good air around instruments, of course this also depends on the filters, the Black, Blue and Orange having the most air, with the Pink and Copper being more closed in. Instrument separation is very good overall, and they have good PRAT allowing even faster mixes to be easily picked apart.

What is very impressive about the R1 is the detail retrieval with all the filters, these have the ability to pick out detail the other IEM's around this price range struggle to. These are a very fun IEM but they are backed up by incredible detail and control, few other headphones give you this technical performance coupled with a fun sound.



£500 is not cheap for an IEM, especially since you can get the excellent Dunu DK-3001 for the same price. But with the R1 you can change the sound signature with the filters, and the differences between them are big. The stock Black filters are superb for an engaging and super fun on the go IEM, with the Blue having a more neutral but still engaging sound.

The R1 is a great first product from IMR, and I am really interested to see where they go from here. As they stand, if you want a fun sounding IEM, then you need to check out the R1 as I don't think you'll find an IEM that is this powerful and enjoyable at this price. If you want a more neutral and smoother sounding IEM, then I suggest looking elsewhere. These will get your feet tapping, that's for sure.

Sound Perfection Rating: 8.5/10 (Overall looks could be sleeker, the packaging doesn't scream high end, but they are extremely fun to listen to, with the ability to tune the sound signature)



Pros: Read my text
Cons: None
Not a product review per say, but still belonging to this space.

I believe I have read every single word in related to the infamous TA and some want to equate IMR Acoustics to TA, undeservedly. As a new, very satisfied, owner of a pair of R1s, I want to share my experience.

I have learnt about Bob’s previous work and when I saw the design of the R1, read about the philosophy behind his latest creation and read a couple of reviews, I took the plunge and preordered, without hesitation. For me, talent and dishonest behaviour usually don’t go hand in hand, and Bob is a very talented engineer and designer. Passionate people, who invest their soul in their trade, deserve our attention. Honestly, I am not capable to review an IEM and I lack the experience to evaluate it against other competitors, so I leave this task to other profesional reviewers. Nevertheless, I know what I hear and am totally pleased with the R1s lush, powerful and musical sound. The build quality is excellent and the fit in the ear is very comfortable, with small size and no sharp edges. I value highly the open ports as a way of easing preasure in my ears and, hopefully, preserving my hearing. Good cables with 90º jacks, both 3,5mm & 2,5mm, generous accessories and classy packaging. My expectations have been overcome to the fullest and I am delighted.

Finally, I want to tell that Bob fully lived up to his word, has been very attentive and proactive and made sure I got my shipment in time. Later, he took care to inquire if the goods were delivered and if I was satisfied. What more can I ask for in customer care? I know when I meet a gentleman and Bob is one of them. He deserves all credit for his work and success in his new venture. Well done Bob and I wish you the very best!
Pros: Clear and consistent sound across all genres.
Fantastic deep rich bass that packs a punch.
Built like absolute tanks
Ceramic driver definitely separates this product from the crowd!!
Cons: None as of now


Hello everyone! This is my review of the IMR-R1. Who is IMR?

IMR is a new company started by well established audio fanatic known as Bob.

The company aims to start a new chapter in Bobs career and for him to pursue his goal of creating some of the world's best sounding earphones. And he’s done a damn fine job if I do say so myself.

The IMR-R1 are utilising a special driver that is a combination of Beryllium and Ceramic. The reason for this is that there are limitations of other setups that Bob aim’s to overcome with this new technology. Rather than focusing on driver count and worrying who’s is bigger than who’s, the aim here is to create something phenomenal. Beryllium and Ceramic both have their individual strengths, both of which are present here.

Tech specs:

  • IMR Open and close porting system

  • 5 Audio filters

  • 2 Pin detachable cables

  • Impedance: 32 Ohm

  • Sensitivity: 108 +/- 3DB

  • Frequency response: 14 - 40000Hz

  • 24ct Gold plated 3.5mm Jack

  • 1.4M length OFC cable

  • 13mm driver featuring Neodymium motors with beryllium diaphragm + Ceramic driver

Before I start, I would like to thank Bob for allowing me to try these after many weeks of begging! ^_^


I’ve studied design for 9 years now and have worked in the audio industry with one the UK’s highest regarded manufacturers. Design for me is a huge part of every product I buy, ergonomics, feel, materials, features, product longevity, I wouldn’t say I’m picky but it’s definitely 40% of my reason for buying something.

To start with the IMR’s design is quite fascinating. Looking at them you might think they are uncomfortable, however this is quite the opposite. I personally am a fan of their aesthetic. I’ve never been into flashy products with gold and all that crap. I feel the IMR focuses on sound quality, but somehow manages to look great. I love the attention to detail and the industrial vibe the hex screws give off. Shows that these are a REAL product that has received time and effort to create, it's definitely not to be messed with.

Material wise, these things are built like a tank. Extremely strong exterior, and the removable cables have a very satisfying feeling when removing them. The rotating vent covers on the side of the housing are very easy to operate, so much so that I was able to adjust within seconds without having to take them off. Something I was VERY happy about considering some tracks require that extra width.

I wore these for an hour straight at one point during my testing and didn’t suffer any discomfort or fatigue whatsoever.


With this being a universal IEM, isolation is going to depend on what tips you’re using. By this I mean brands like Comply are going to supply you with a better seal. During my testing I found the isolation to be good, using my rubber tips. (I couldn’t find any comply)

In regards to letting sound through the body of the earphone, I found none more than any other earphone, microphonics were non existent due to the wrap around ear design.


I guess this is the main attraction of any review so I had best put the earphones back in while I write it.

My test gear for this isn’t anything fancy. I’ve owned a few DAP’s in the past, Questyle QP1R and an AR-M2, however I just don’t find myself using them as much as a phone with a good headphone jack, too bulky.

The earphones come supplied with an array of filters that vary the signature of the sound, some people prefer a warmer approach, where as I go for the silver filters which brings out the high and low end.

For this I will be using a Oneplus 5 with a Qobuz sublime subscription.


Rather than splitting this up into sections regarding the bass and treble, I’m opting for a general written description of the sound.

The signature of the R1 is rich and punchy. It an extremely expressive piece of equipment and is an absolute joy to listen to. The accuracy of the sound is spectacular and presentation is very well spaced without giving that “concert hall” vibe. It expresses a very “there in front of you” feeling, which in turn triggers that shiver down spine feeling I got with the iSine 20.

The mids and high’s are extremely well received here also, something I think bob was going for with the Ceramic plate. One track that absolutely strikes this is the opening of “Ain’t no Sunshine - Eva Cassidy”. The plucking of the guitar possesses depth that I’ve not come across before with another IEM, not only that but once the vocal work starts, I was astonished by the differentials between her, the bass and the guitar, which surpassed even further expectations at the introduction of a piano. The separation here is not something I would expect from a unit with this few drivers.

My second test track for this review is Dust bowl Children - Alison Krauss, Just adding here I ain’t no hillbilly. But my father was always a big fan and it’s just something I’ve picked up. For those who know the track, there’s a lot going on here. It’s a fantastic demonstration of the R1’s ability to present a magnitude of instruments simultaneously. That little banjo is really going for it right in the background and you can certainly feel it.

The third track is Owl City - Fireflies, the candlelight singer songwriter known as Owl City loves to work that treble in areas not many others would even think of. This track was selected to get a feel of the treble. One thing that I really hate is harshness of treble and it’s far too common to find that I have to EQ the heck of the high end just to stop my eyes squinting. This testing was done with a flat EQ and I had no issues listening to any of my music. What really surprises me is the resolution of the treble. Ceramic is an extremely brittle material, and I did initially have my reservations about whether my dog would run away screaming if I asked him to try these out. However the sound was very clear and consistent even at the higher end of the spectrum.

The mids of the R1 are very lush and are not left out. My track for this was

Hey now - London grammar. The bass in this track is very present and requires good sub bass presentation in order to fully accentuate itself the way the artists intended. I chose this because I wanted to see where to vocals would be placed in comparison to the bass. Pleasantly the mids weren’t suppressed at all and her voice was

very much present.

Switchable Open and closing port

A major selling point of the R1 is the choice of having an open or closed vent. This of course gives the effect of a wider presentation, some tracks definitely take advantage of this and sound so much better with the vent’s open. My personal thoughts on this are that it purely depends on your own personal tastes and I wouldn’t say that one or the other is better. However it is a very welcome feature and something unique that doesn’t hinder other aspects of the product, but instead makes it all the more compelling.


To conclude

The R1 from IMR is an excellent product. It definitely competes with products within and above it’s price bracket, having tested and compared these with the iSine 20 from Audeze. I would say I prefer the less ridiculous aesthetic and build quality.

The sound is simply spectacular and I feel the combination of Ceramic and Beryllium has definitely paid off here, so hats off to Bob for doing such an amazing job with the engineering. The R1 is an all round high performer that offers a very engaging sound which surprisingly performs very well on my mid range chinese phone.

I would personally recommend the R1 to anyone looking for a very complete audio experience that doesn’t require a thermonuclear reaction to power it. In a highly saturated market with so much choice, it’s difficult to find that “one” that sticks out.

All I’m saying is I know which one I’d go for knowing what I know now.