Symphonium Audio Crimson


aka JP-nums or JP-numbers
Lead Organizer for Can Jam '09
Symphonium Crimson - One persons two year journey to find the One
Pros: class leading transparency
best headstage in its class and above
best tonality I've heard in this price bracket $1.5-$2.5k
Bass is deep but extremely well controlled
Cons: slight peak in the upper mid/low treble that while not sibilant on the wrong recording can show itself
The nozzle is fairly wide so tip experimentation is required
not a fan of the can style case, needs to be wider and maybe more shallow
Symphonium Crimson - One persons two year journey to find the One

First it is important to know this is just a review, one persons opinion (YMMV). The unit being reviewed was purchased by me at CanJam London for full retail.

Who am I, what do I value in audio reproduction and what’s my basis for comparison. Well I started down the audiophile rabbit hole with speakers in 1992 with my first pair of Alon 1 speakers. These were highly transparent but with deep tight bass response. As they years went on I fell in love with horn based speakers like the Altec Lansing Voice of the Theater and more recently OMA (Oswalds Mills Audio) Imperia and Mini as benchmarks.

I fell into headphone listening only due to a change in living arrangements, shorthand for I moved in with a friend and they weren’t going to indulge my audio gear in their living room. In late 2004 I joined Head-Fi as a short stop gap to find headphone audio to fill in this gap. Almost 20 years later I'm still here enjoying the people, music and gear (in that order).

I have owned AKG K-1000a, Grade PS-1, RS-! Pink Drivers (wow try these), RAAL ear speakers, several Stax headphones… My current full size drivers are the LCD-5 and HifiMan HE1kse. In ears I was there for the start of JH audio in 2009 and had 3 of his units (13, 16, Lola), also the Sony ier z1r, FIR M5 and I currently own the 64 Audio U12t and the Sony M9. I’ve auditioned countless IEMs at multiple CanJams and find two truths: 1) the IEM space has seen the greatest qualitative growth in the Head-Fi space over the past 5 year then any other category and 2) the sweet spot for me in IEMs is the $1500 to $2000 range. I have heard a lot of crappy weird sounding IEMs in the $3000 and up range that are just plain wonky. At Can Jam London I was searching for an IEM that could potentially dethrone the 64 Audio. This is a tough ask as they are pretty highly regarded and are normally found in the top 3 or 5 IEMs by reviewers that stack rank al products regardless of price.

I tend to favor a fast dynamic sound but also need deep tight bass that won’t overshoot into the mid range. I listen to primarily Classic Rock, Grunge, some classic metal, Jazz primarily from the golden age of 1957 to 1965 but wander out of that range a bit for great stuff and lastly blues music. I need a transducer that will make my toes tap and cause me to involuntarily smile or air drum without consciously being aware of it. Timbre aka tone quality is vital as I attend many concerts and play guitar and bass (woefully mediocre but joyously) so I have heard a wide array of actual instruments in many different spaces. A touch of warmth is ok but too much and the music loses its drive and vibrancy. So you could say I value PRaT and transparency.

I like to take a few weeks to sit with a piece of gear prior to writing a full review as sometimes gear that wows at a show or in a quick listen can fatigue over time and sometimes the shy wallflower comes to life and reveals greatness after a week or two.

Ok dude enough about you and blah blah blah… Did you like the Crimson or didn’t you?


I tried these pretty much directly following an audition of the Helios SE and then the Subtonic Storm (these are the best I have ever heard). I really liked the newly tweaked Helios and fell in love with the Storm (my wallet said no). I was expecting to be let down as how could test the Crimson directly after the Storm and not be let down? I was not and I was giddy with excitement at how much I enjoyed these.

Bass - This is a tough one as this may be my favorite IEM for bass reproduction and it’s not the quantity but the quality and how low these play. They have nice sub bass reproduction. The bass is fast and you can follow the bass notes extremely well better hear the cane in pitch than other IEMs I have tried. The bass has incredible texture as well. Listen to a Hammond B3 low notes and it brings chills, Charlie Hunter (Everybody Has a Plan Until..) it almost feels like a visceral impact to the body (although that is physically not possible). There is no bass bleed into other regions. Total win for me here!

Midrange - ok for me the test here is guitar, sax, trumpet and vocals. I can be sensitive to upper midrange brightness. This is my one caveat with these in rare instances there can be a touch of glare with some guitar sounds. I have experienced this extremely infrequently and it may just be the recording but for those with a similarly sensitive to this I thought I would mention it. Now for the good and oh I mean great stuff. TIMBRE in spades my friends. Guitars come to life with these in a way not heard by me in an earpiece. Last night I put on Let it Be by the Beatles and there is an iconic solo and the detail, tone and transparency had me feeling like this was the first time haring this song. As I explore my collection over and over gain I am hit with this experience. Vocals are super clean and clear, they come right out of a deep dark silence to appear hanging right in front of you. These also portray vocal nuance like throat or mouth sounds well. I have had several emotional/hair raising moments with these.

Treble - highly extended, at least for these late 50 year olds ears. My hearing has been tested and it is surprisingly good but age does what it does to hearing. I find the treble well executed and may be the reason for the wide stage and detail retrieval. There is a lot of information in the treble with these but oddly it is never overdone or harsh. I can’t fully explain it, it is there when you need it but it doesn’t push the instruments into harsh or exaggerated sounds. This is also an area that provides great instrument location and overtones that can really bring out the quality of the sound.

Dynamics - These are to my ears very fast sounding earpieces with a great degree of accuracy. They may favor newer masters with a fuller range of bass. All in all I found these a lively listen with great macro dynamics and very good micro dynamics.

Separation and Stage - Not sure how they did this in an earpiece but the head stage is pretty wide with sounds appearing extremely well localized in a 180 degree plane from your ears around you. You can tell the designers really focused on driving separation of sounds as you can clearly pick out each instrument in space in a way not present to this degree in any earpiece I have owned. Clarity is second to none (ok, ok, with the exception of the Storm)

Sonic Quibbles - If he mix is weak sauce then bass is not going to be great, my other pieces seem to homogenize this to a degree. There can be upper mid peaks for me, this is most present in guitars in rock music but only shows up infrequently

Fit and Finish - Fit good but I did need to experiment with several tips to get a fit that was comfortable. I settled for now with the AZLA Crystals. Normally I am a medium but due to the larger nozzle size I needed to size down to the MS to get a fit that sealed well and was comfortable. These are pretty comfortable in my ears with no part of the outer shell creating rub spots or pain. I like the look and the forged carbon has grown on me. The 8 wire cable provided to the early adopters is well done and has good flex. I would love an ear wire for the cable around my ear but I can always add one later. I have pretty much exclusively used the 4.4 as both my daps and my usb dongle docs have this as well.

While I have used many songs to audition these over the past few weeks. I largely focused on a few songs I have used over the past 30 years:
  1. Eric Johnson 40 Mile Town
  2. RATM - Killing In The Name Of
  3. Mad Season - River of Deceit
  4. Miles Davis - Shhh Peaceful
  5. Led Zeppelin - Babe I’m Going To Leave You
  6. Bill Evans - My Foolish Heart
Equipment Used - Shanling M6 Ultra, Ibasso DX320 (amp12) and FIIO BTR 7.

The Crimson is somewhat ruthless with the source and the Shanling and Ibasso showed up well with the Crimson. The FIIO sounded a bit harsh and listening fatigue arrived after about an hour and the timbre was just not as good. So all comments are based on the sound I got from the DX320 and M6 Ultra. I did need about 20% more volume subjectively compared the the 64 audio but at no time were the Crimsons hard to drive. I use medium gain on the devices and on the Shanling for instance it never goes much above 20. On low gain maybe 28 is needed so no worries for powering these.

Now on to comparing these to what’s in the current line up. You know you are truly crazy when you take three sets of IEMs with you on a trip to France so you can complete a review :) . Comparisons used the above tracks in more of a stream of consciousness approach.

Crimson vs 64 Audio U12t (m15 module) - U12t excellent but softer sounding bass is fatter but also significantly less defined. Treble on the U12t slightly more diffuse and delicate. Greater perception of details and sense of space with the Crimson. Layering better with the Crimson. Greater midrange presence on the Crimson. It takes several seconds to adjust to the change between these two as they deliver very different experiences to my ears. The 64 audio has good technical chops much has a bit of a warmer sound while the Crimson is significantly better technically but somewhat drier. Crimson delivers more tonal information for guitar sounds it is pretty noticeable. When switching back and forth coming from the Crimson going to the U12t the sound felt veiled and a bit closed in. Overall I prefer the Crimson although the mighty U12t is still a top flight IEM. The cost of the U12t new is $2k vs Crimson at $1.5k at release. Buying new I’d tip my hat to the Crimson.

Crimson vs Sony IER M9 - This comparison is a bit unfair to the Sony as it is about $1k new versus the $1.5k new Crimson. Similar to the 64 Audio comparison, the Sony is warm neutral so the Crimson is just so much more open and spacious. There is more kick drum impact on the Sony coming from the lows that are not nearly as controlled as the Crimson. The Sony has a nice warmth that I could see as an alternative to the Crimson on nights when your brain needs a rest or like this morning when I had a bit of a hangover from too many beers in a cafe with a new Belgian friend who loves jazz and plays in a band that plays around the world but like most musicians has a day job. Well this am maybe the Sony was a bit more prescriptive for me than the more incisive Crimson. One thing this comparison has also shown me is once again with three IEMs at $1k, $1.5k and $2k price is not the arbiter of what is best (at least for me). So I’d chalk it up to me preferring the Crimson head to head but seeing a place for the Sony as a backup, more warm alternative to the daily driver of the Crimson.

Conclusion - Well if you’ve stuck with me this far you obviously know the Crimson has a strong buy recommendation from me. It’s got the edge in transparency, head stage, tonality/timbre, and the bass is right up my alley. CanJam SoCal is right around the corner as of the writing of this review and we’ll likely see a ton of Crimson impressions so you’ll have plenty of others to juxtapose this review with. Thanks for reading and Thanks to Symposium for continuing to push the envelop!!
Do you know what the driver configuration is? Doesn’t say on their website.
It’s not public knowledge. I couldn’t get the driver setup out of Symphonium at all. They do keep most of their driver configurations to themselves. It has a 4 way crossover so it’s at least multi driver.
4 BA probably. Very efficient crossover design. Nothing wrong with it.


1000+ Head-Fier
Fun like the Triton, Super detailed like the Helios
Pros: Fun and dynamic tuning. Wonderful looks. Does everything well.
Cons: Can be a little too bright with certain ear tips. Rare fitment issues for some.

As a huge fan of both the Triton and Helios, I was beyond excited to see a new Symphonium IEM coming out. I always liked the more fun tuning of the Trition but I wanted it to have the detail and magic the Helios provided. I initially thought the Crimson might be a follow up to the Helios but the marketing seemed to suggest the Crimson would have its own tuning. The Crimson doesn’t have any public info on the driver count or even what drivers are being used at the moment. The Crimson comes in at $1499.00

Quick shoutout to my friends running a short tour before CanJam for sending over a production unit to check out on short notice. While I always appreciate the chance to test and review products sent in from manufacturers or dealers, it never affects the rating of my reviews.

The Symphonium Crimson can be pickup below:

Onto the review of the Symphonium Audio Crimson! My personal preference is a hybrid/tribrid IEM where I get good hitting bass and have a detailed treble with decent mids. When it comes to an over ear headphone I prefer a spacious sound with a deep low end, the mids to be more forward and the highs to be a little bright with some sparkle. I listen to a lot of genres but I hover in the classic rock, blues and edm music with some rap here and there.

Gear Used​

IPhone 14 Pro Max with headphone adapter, Hiby R6 PRO II, Letshuoer Cadenza 12, UM MEST MKIII and Everolo Z8/SMSL SP400 stack

Looks and fit​

The Crimson comes in a nice black shell that isn’t overly heavy. The outer faceplate has a really nice red outline and the faceplate is a nice mix of what looks like carbon fiber with a little red mixed in. I had a softer feel to it so maybe it's a different material. Regardless, it's quite a beautiful IEM to look at in person. It’s also about a medium size shell compared to other IEMs in the $1K+ range.

When it comes to the fit, I know both this and the Triton/Helios fit others ears just fine with no problems. I’ve had a different experience only with Symphoniums IEMs and due to their fully sealed design(no vent holes), I have an issue with their IEMs causing too much of a seal when I use them. No matter the tips, I get an extremely strong seal that causes eventual over-pressure discomfort and a headache after an hour or so of listening. I’ve not had this issue on sealed CIEMs in the past so this is less of a design issue and more that all the Symphonium IEMs make the ultimate pressure seal in my specific ear canals. I’ve not heard any other person complain about this issue I’ve had. Had this been a vented IEM, I think it wouldn’t be an issue for my ears. I do however like the slightly smaller shell design.

Isolation and sound leakage​

Since the Crimson is a sealed design, It has wonderful passive isolation. It also doesn’t leak sound(at least from arms length) which makes this a good option for those in quiet areas that want to listen at louder volumes without disturbing others.

Packaging and accessories​

Since I got a tour unit on a short notice. I only got some tips, their standard carrying case and the new stock cable with a swappable plug. I will mention they have included some very good tips. I’ve been wanting to try the Divinus Velvet tips for a while now and they include them with the Crimson and they are a wonderful premium tip. Same thing with the standard Sednafit 2 standard tips they include. These tips will also be included for those who buy the retail units.


These final impressions were done off the Eversolo DAC-Z8 connected to the SMSL SP400. These impressions are what the Crimson sounded like to my ears. This was also using the Spinfit W1 tips. Things like ear tip selection and DAC/amp selection will produce different results and impressions vs what my ears hear on my specific gear.

I will note that the Crimson does benefit from tip rolling and I’ll be listing my impressions with my preferred Spinfit W1 tips. The treble seems to be affected the most by tip rolling. I found the W1 tips sit on the more sharper side of treble when paired to the Crimson but I like this pairing regardless.

The Crimson has a nice strong bass response that provides very good slam and impact in the sub bass region. It has a more balanced mid bass so it sounds strong yet controlled. On the first listen I had quite the smile from the bass hits on the first few tracks I listened too. I really enjoy a strong bass like this that doesn’t overpower the rest of the tuning. The mids are very detailed and don’t sound artificial. Same thing with the vocals. Very detailed and life-like instead of sounding metallic or artificial at the upper end of the vocals. The upper mids aren’t super boosted but they sound fast and accurate. Somewhere in the lower treble(maybe upper mids) I do hear a more spicy peak. I would call this a more overly sharp sound vs a sibilant or splashy bright sound. I found that tip rolling did affect this amount of sharpness and I later confirmed that this can happen with some tips on the Crimson. With the Spinfit W1 tips I used, I did find the treble to sound sharp but with a fast decay so everything and I hear a nice sense of detail. The resolution the Crimson provides is indeed top notch and I found it competes with some IEMs that come in at a high price. Overall, a wonderful tuning that is well executed.


The Crimson is a surprisingly wide sounding IEM with a good amount of depth in the soundstage as well. This is probably one of the better examples of good staging and imaging. I didn’t quite experience the neat imaging I remember the Helios provided but overall a very good IEM for those hunting a wide and deep soundstage. The imaging was spot on and I was able to pick out details in busy tracks with ease.


The Crimson is a little harder to drive than most IEMs on the market. This is the same thing with the Helios and Triton. While I think it can run off most modern source gear, I think mid-range source gear will provide a bit more detail and staging. Since it’s harder to drive, I had no issues with floor noise/hiss when running balanced.

Stock cable​

The stock cable looks like their prior cables but it now has a swappable plug at the end which is a nice addition. It looks like the plugs I’ve seen on a lot of newer IEM cables so it might be compatible with other plugs but I would still stick with the OEM plugs if possible. The cable has no ear guide which I think makes sense due to the shape of the Crimson shell. I personally prefer a ear guide but for Symphonium’s IEMs, I like it without the ear guides.

IEM comparisons​

LETSHUOER Cadenza 12​

The Cadenza 12 is still my all time favorite TOTL IEM to date. Keep this bias in mind as I tell everyone that I do like the Cadenza 12 over the Crimson. This is mostly because I like the highly resolving and neutral sound the Cadenza 12 provides. Both the Crimson and Cadenza 12 have what I would consider vastly different tunings. The Crimson is a dynamic sounding V/W shaped IEM that works very well with everything. The Cadenza 12 is a neutral turned IEM that also does mostly everything well but just a bit more safe. The Cadenza 12 can’t compete with the treble energy the Crimson provides but I found the detail retrieval to be slightly better on the Cadenza 12. Does that constitute a $700 price increase over the Crimson? Not even close. However, I do really enjoy the tuning and fit of the Cadenza 12 over the Crimson for my ears specifically. Read my note on fitment above.


Both the MKIII and Crimson do wonder bass and soundstage/imaging. I’m gonna start off by noting that I found the MEST MKIII has some of the widest soundstage due to their unique bone conductor. Which provides a neat light echo to the entire stage which gives a high sense of space in tracks. The Crimson is just really good at a big sounding stage but without any of the tricks. Which is impressive given that both have about the stage soundstage width and depth to my ears. The bass impact on both is fantastic but I do find the bass sounds a little more controlled on the Crimson but doesn’t lack the slightly thinner mid bass the MKIII has. The mids on both are about the same with both sounding accurate and natural. The vocals on both are darn close to my ears and neither are artificial sounding. The big difference comes to the upper mids and treble. The MKIII has more upper mid presence and then starts to trail off in the upper treble. The Crimson can be much sharper sounding in the treble area and it has way more energy in the upper treble unlike the MKIII. I think this is where one has to choose very strong treble performance or a safe and more tame treble between the two. Both pull in great details and the resolution on both is really good.. For my personal preferences I really like the Crimson tuning but I have a hard time choosing between the two.

Amping Combinations​

Hiby R6 PRO II​

The R6 P2 is my favorite neutral-warm DAP and I like the pairing with the Crimson. The R6 P2 does well at not coloring the sound when listening with the Crimson. It also does well at bringing out a bit more energy when paired with the Crimson. The bass is nice and strong, the mids are fast and accurate, the vocals are smooth and natural sounding. The upper mids and lower treble do sound a little less intense here but I think the upper treble is still fast and detailed. Staging is close to the desktop stack I use but still very wide and deep sounding. Overall, an easy pairing to love.

Eversolo DAC-Z8/SMSL SP400​

This desktop combo is what I use to review all my current audio gear with. I think the Crimson does scale with better gear and I found a small but noticeable difference going from my DAP to something like my desktop stack. I think any mid-rang source gear wise will be enough to make the Crimson sound great. Maybe avoid overly cold and bright sounding source gear as I can see that negatively impacting the upper treble if paired with the wrong tips.

Overall thoughts​

So where does the Crimson sit in the Symphonium lineup? Well for me, I think it pulls the best parts from both the Triton and Helios and it very much feels like the perfect mashup of the two tunings. Ignoring my weird fitment issues with all of Symphonium’s sealed IEMs, I absolutely love the tuning and performance the Crimson provides. So on that high note, I highly recommend the Crimson! If anyone goes to the upcoming SoCal CanJam, definitely give it a try! Symphonium Audio does really well at spending time to design well tuned IEMs. They continue to be one of my favorite audio companies and I think as long as they continue their trend of high quality over quantity in their product line, they will continue to be one of the top players in the IEM market. Great job to the team and I look forward to what comes next. Thanks for reading!!!
Compared to my desktop stack, I 100% agree.
Smirk 24
Smirk 24
Good to know! I needed a sanity check as I received my R6 Pro II rather recently.

What desktop stack do you use for your IEMs?
I'm using an Eversolo DAC-Z8 DAC and SMSL SP400 headphone amp