It is with great pleasure, and with thanks to RHA (as well as nmatheis for helping to organize the North American leg) that I can say that I have been selected to take part in the RHA listening tour. During this tour, I have 10 Days to listen to & evaluate the CL750, CL1 ceramic earphones, and the Dacamp L1, a digital-to-analogue converter with class AB amplifiers. Although I am very grateful to be able to participate in this tour, I receive no compensation other than the joy of listening to these items in the comfort of my own home, and the following review is my honest opinion.
 
Here’s some info paraphrased from their website:
 
-Stainless steel housings for durability and longevity in addition to low internal resonance
 
-High conductivity oxygen-free copper cable, coated in durable TPE with stainless steel reinforced cable divide and terminations
 
-High impedance (150 Ohms), it is recommended that you use them with a headphone amp (such as the RHA Dacamp L1)
 
-3 year warranty, $139.95 (USD)


 
This is my 1st experience with any RHA products. RHA has a reputation for a robust build quality, and I can honestly say that the CL750 lives up to that reputation. The Stainless steel housings are striking, and their long term durability seems evident to me. They do feel heavy in the hand, but they never felt uncomfortable during any of my listening sessions. The cable is braided oxygen free copper, quite robust, attractive (IMO) and was mostly microphonic free during my listening due to the over ear orientation. As durable as the CL750 seems, there is an incident of note that needs to be mentioned. While shoveling snow, the volume in the right earpiece dropped to an unlistenable level. It seems likely that this was due to moisture since I was exerting myself, however the cause has not been diagnosed. This leads me to believe that these would not make good earphones to exercise with. I am not overly concerned since every manufacturer has problems occasionally, and I haven’t heard of anyone else having problems on the tour. The defective unit was quickly replaced so that the tour could continue.
 
Comfort was very good overall, with the housings sitting securely in my ears. The biggest problem for me comfort wise pertains to the size of the nozzle which exerts a little pressure with any tip I chose. This wasn’t enough for outright discomfort, but I was always aware that there was something stuck in my ear (more so than with some more comfortable IEMs I’ve used from Shure & Westone). I personally have a challenge with IEMs in general due to my left ear canal being smaller than my right, but I found a good fit among the abundance of tips provided by RHA. There are a good amount of accessories included with the CL750. There’s a 3.5mm to 6.35mm adapter, a truly generous amount of tips (11 in all, including 6 pairs in various sizes of single flange, 2 double flanged and 3 genuine Comply Tsx-200 ) a stainless steel holder for the tips, shirt clip, and a fairly large carry case.




 
Before I offer my listening impressions, I’ll start with a little about myself. I’m pushing 50 and have less than perfect hearing (50 is pushing back). I’ve been a music lover for as long as I can remember, and I learned to listen a little more critically during the few years I sold audio equipment (and the more I listen, the more I learn). My fascination/infatuation with headphones began about 4 years ago, and has only gotten stronger. The majority of my listening was done listening to FLAC, WAV & various MP3s with primarily RHA’s own Dacamp L-1, assisted by my Shanling M2, Fiio x3 (1st gen.) or my HP all in one PC  acting as a source. My tastes are fairly eclectic, but my listening centered on classic rock, folk, jazz, classical and various genres of EDM.
 
At 150 ohms and 89db sensitivity, The CL750 is not easy to drive. These earphones do best with a decent amplifier, whether separate or within a dedicated DAP. Plugged directly into my Samsung Galaxy S7, I could certainly achieve adequate volume and the dynamics didn’t suffer much, however I found my Fiio and Shanling to be a noticeable step up in fidelity. The Shanling sounded great at about 30-35 out of 60 on low gain, and when paired with the ALO National the CL750g faired even better. However when paired with the Dacamp L1 I found there was a certain synergy (no surprise there) which is why I did the majority of my listening with that combo.
 
The CL750 is endowed with a full and healthy bass that isn’t overly pumped for my tastes, and supports a fairly neutral mid bass, which is slightly elevated but not overdone. Listening to the song ‘Moorish’ by The Funky Knuckles, the synth intro & kick drum sounded rich with plenty of life, and never crossed into sounding boomy, which can happen on more bass oriented sets. The bass, while energetic enough for EDM, didn’t sound out of place when listening to classical or other acoustic music. Well done RHA.
 
Describing the midrange, the word ‘lush’ comes to mind. Vocals never fell so far back as to be called recessed, but there is a bit of a shroud that mid-heads would not appreciate. While on random, I came across George Thorogood singing ‘Purple People Eater’ of all things, and I found myself enjoying the song. To use this song as an example his voice, which sounds fairly neutral on, say, the HD600, sounds like he’s standing a step further back in the room with the CL750. A song like Madeline Peryoux’s ‘Instead’ sounded a bit more natural overall, even if her voice sounded a little less husky than I’m used to.
 
Moving into the treble is where we run into some potential issues. While I found the treble to be somewhat peaky I didn’t find it too bothersome. There is a little extra shimmer up top that some will find problematic, yet some will likely enjoy. The tone never sounded unnatural to me, but there were times I thought the treble was a little over energetic, again, without being annoying. The cymbals & high hats in Cheryl Crow’s ‘My Favorite Mistake’ took on a pleasant forwardness, and the strings in Zigeunerweisen Opus 20, (written by Pablo de Sarasate) had a wonderfully vivid presentation.  The biggest problem, though is that sibilance is present in the lower treble region, so be forewarned. The S’s in the MP3 I have of Valarie June’s ‘Somebody to Love’ is unpleasant at best. Letting RHA’s Dacamp L1 work its magic by decreasing the treble helped tremendously. Once I dialed it back to -2, the treble became much less obtrusive.
 
Overall, RHA did a heck of a lot right with the CL750. Whether you hold the driver problem against them or not, the build quality, from the stainless steel housing to the robust braided cable and steel termination suggests a product more expensive than its present price. The sound signature has a lot going for it, even if it's not for everyone.There is an issue with sibilance, and some will prefer the midrange to be more forward, but when you tally up a great build, excellent bass, decent midrange, and energetic treble and you have an IEM that I think is going to appeal to a lot of people.

Disclaimer
 
I got this unit as part of Australia/New Zealand tour arranged by @RHA Team, thank you very much for including me in this tour
 
Introduction
 
I am just another music fans in this world, I love listening to music, and that made me stumble into head-fi around 10 years ago when looking for the best way to listen to my music. I am not in anyway an audiophile, heck not even close, so please forgive any lack of details in my review. Most importantly this is my personal impression on the unit, most likely i heard things differently than you, my ears, my preferences, my brain
 
I've listened to RHA CL750 for about 4 days. I've used them with LG V10, Walnut V2 DAP, and through RHA DACAMP L1 . The source will be either my personal music or google play music.
 
Music preferences
 
My music preferences is mostly instrumental, whether it's Classical, Jazz, Celtic, New Age, etc. I also enjoy music with vocal on them, but my playlist is mostly instrumental. I would say around 80/20 mix.
 
Example of the music I listen (not limited to):
- Acoustic Alchemy
- Tony McManus, Soig Siberil
- Hawaiian Slack Key guitars
- Fusion Jazz (Lee Ritenour, Dave Grusin, Fourplay, Special EFX, you get the idea)
- Akira Jimbo, Tetsuo Sakurai, Casiopea
- Incognito
- Europa Galante/Fabio Biondi, Musica Antiqua Koln, Rolf Lislevand
- Yoko Kanno
- Madonna
 
Sound signature preference
 
Hmm...not sure what my pref is, I enjoy Fostex TH-600 very much, It's one of the best headphone I've heard, so that make me a fan of U or V shaped sound signature.
 
Having said that I also enjoy ZMF Blackwood which have mid-centric sound sig compare to the TH-600, so i guess i am flexible
 
My typical listening gear is: Asus Xonar STU -> Project Polaris -> ZMF Blackwood
 
When travelling I usually use MEE P1 straight out of DAP/Phone.
 
Build Quality and Design
 
This is the first time I use RHA product, and I am quite impressed with the build quality of the CL750, the silver casing is pretty solid and smooth, and not heavy at all. I also like how they cover the cable with a transparent plastic tube/rubber?, no microphonic sound at all, although when it's tangled they kind of make them hard to untangle. The ear guide is ok, although i would prefer a more stiff ones.
 
Sound Quality
 
Ok the most important part for me, sound quality, so how do they sound? They have a classic V shaped sound signature, treble and sub bass is emphasized, mids is recessed but still enjoyable. Music sounds clear and crisp, but can sound a bit thin or hollow.
 
When I tried them the first time I have a bit of trouble with the fitting, apparently I push the tip too much and that stop them from getting a good fit on my ears, and without a good fit, they will sound very hollow with harsh treble and lacking bass, so if you tried them out and find them sounding bad, maybe it's not fitting your ears properly.
 
I listen to a lot of acoustic guitar music and I found CL750 sound sig quite enjoyable, string sound on higher frequency sound crispy and clear thanks to the elevated treble, however i did miss a bit more mid bass that will bring body to the string sound.  From my experience, instrumental music sounds great with CL750, even though the mids are recessed you can still enjoy them.
 
Hearing female vocal is a bit different, it's very dependent on the mastering (and maybe quality of the source as well), for example, I tried listening to Vanessa William - Colours of the Wind and the sibilance is very obvious. Madonna - Cherish is almost similar experience. From what I can hear both recording is a bit bright, and the CL750 sound sig just elevated them even more. However, not all vocals are sibilance, for example Orange Pekoe - oriental jazz mode sounded just fine to me
 
I do found solo piano to sound great with them, most of the solo piano recording i listened to tend to sound bit dark, so CL750 fits them well, in my opinion anyway.   
 
Having said that, if you don't mind using EQ, i find that lowering the treble really make them shine, with the treble reduced, you can hear the mids clearly and they actually sound very nice.
 
Comparison
 
RHA CL750 vs MEE P1
 
Coming from MEE P1, I can't help to notice the absence of the mids on the CL750, it's there but definitely outshine by the treble, it's bit shocking in the beginning. However as i used the CL750 overtime I didn't really notice the recessed mid as bad as before. The treble on the P1 is never sibilance, and in my opinion is perfectly balance with the mids. 
 
So MEE P1 have more balanced sound signature compare to CL750, with some slight mid-bass hump on them than given them a warm sound sig. I notice that CL750 have a bit more sub-bass (probably around 60hz region) while the bass on MEE P1 is more pronounced on the upper region (maybe around 110hz and above). 
 
If i have to pick it would have to be MEE P1 for it's more natural balanced sound, but with a bit of EQ CL750 is pretty close behind them.
 
RHA CL750 vs CL1
 
WHen i listen to CL1, i have and immediate feels that the CL1 is like the big brother of the CL750, very similar sound signature but more, specifically more bass and treble. More bass - great!, more treble - ah, not so great for me. CL750 alread a bright IEM by default, and CL1 somehow add even more trebles make them sounding hyper-clean and bright, while this might be favourable for some music, when you hit those bright recording it's really painful to hear them.
 
Again, with EQ they can be a better IEM, I prefer the bass of the CL1, but prefer the treble on the CL750, so a bit undecided here. However comfort and build wise CL1 is way better than CL750. 
 
Summary
 
If you read through my review, you might get the impression that I don't really like them, but the truth is I quite enjoyed them, I listened to them nonstop for hours on the Walnut V2 (great pairing here) and only if I compare them to the MEE P1 then I realized the recessed Mids.
 
If you like V shape sound signature, bright and clear sounding IEM, give RHA CL750 a try, they might be the right IEM for you.

Box & Accessories 

 
Was greeted by a high quality packaging , and the neatly arranged CL750  .
Under it was where the documents and accessories were stored . 
 

 
The quality of the entire packaging felt luxurious , what's included is a 1/4" jack , which has the same stainless steel case as the jacks , a high quality case which was padded and a significant improvement over the previous RHA case . The previous RHA case made of leatherrette peeled at the edges where they were most contacted with . Overall the new pouch looked like it could sure stand the test of time and daily torture . Like RHA products , they provide a vast number of silicone eartips from dual densities to foam , all at different sizes , so you'll never have an excuse on not getting the perfect seal ! 
 
Audio


 

RHA sent the review unit to me for demo , Do note that the review is done in no particular favor of RHA , and i do not get to keep them . What you are about to read would be an honest impressions from my point of view , however your mileage may vary . I did not went to read about the IEM before hand and have zero knowledge on the retail price or any technological "breakthroughs" to note . This is to keep the review as fair as possible , by just blind hearing them . 

My Current daily driver is the MA750i , it has been so for over a year , it was also the most interesting and forgiving IEM i have ever heard . At the MA750's price range , it was a sure-recommend for those who are looking for something musical and smooth after the lengthy burn-in period of about 3-4 months on listening . For those whom have not heard the MA750 , you should be informed that the sound fresh out of the box was harsh , metallic and emotionless , pretty much like the CL750 which i have now . A pity RHA did not burn in them before sales , because the MA750 is excellent after burn in , one of the most obvious improvements i have ever heard in an IEM , it was also the IEM that made me believe that burn in can be this drastic . 

So , being an avid fan of the MA750 + iFi iDSD Micro pairing , i could only expect the pricier , revised model to be better in every aspect . However , i was slapped with great disappointment . The CL750 was emotionless , harsh , metallic , a pain to listen to , and unfavorable with every ear , i went to pass around my group of audiophile friends , and every single one of them disliked it . if 2 of 5 of my friends liked it , the IEM stands a chance of being a love-hate IEM . However , 5 of 5 of my friends disliked it , this proved that the tuning was unattractive , that 100% of the people whom i passed it to , disliked it . 

I was really enthusiastic about this at first , hence i gave this a try before the CL1 and the L1 . The very moment i heard the sound from these , i wanted to send them forward to the next reviewer in the RHA tour , because i really did not want to write a negative review on their product . But since it has arrived , and i believe that everyone should be aware of their current sound before dropping your hard-earned money on this . I would seriously recommend every individual to give their product a try before purchasing it . Hate to say that one of the worst IEM (CL750) i have heard , and one of my most reccomended IEM (MA750) comes from the same company . 
 
A general description of it's sound would be , artificial sounding , poor acoustics , poor tuning , poor soundstage , poor instrumentations , poor instrumental positioning , lacks texture , lacks resolution , no amping potential , overly harsh in treble , suppressed bass , messy spectrum , lacks emotion , lacks natural warmth , noisy , uncomfortable sounding , it just felt like the MA750's traumatized antisocial younger brother . Every single thing was wrong with it . 
 
Pairing
Pairing with the DACAMP L1 with the 3.5mm was tragic . Overly bright , even with the treble turned down , it sounded unnatural . Everything sounded artificial and extremely unattractive . 
 
Honest Final Thoughts
The audio is terrible . Retailing at S$249 , is daylight robbery ,regardless of the research and material that went into it . Personally i rank IEMs based on their musicality and enjoyment , and completely disregard the price point or technology behind it . This was simply not musical nor enjoyable at all to recommend it to a friend , and i certainly would not pay for it . I would not use it even if it was given to me for free . I apologize to RHA for this frank review , but i believe the Head-Fi community deserves to know the truth . 

The RHA MA750i would still be a far better recommendation option for the price of only S$178 . 

 
RHA CL750 – initial impressions
 
Reid Heath Audio are a Scotland-based manufacturer who will be familiar to iFans, with their T10i and T20i all-metal IEMs being prominently displayed in Apple stores across the UK. Their products have been firmly aimed at the “consumer” end of the market, with models like the MA750 and the T-series occupying the very competitive pricing sectors between £50 and £200. As part of their recent world tour (thanks to @glassmonkey for arranging the UK "leg" and the RHA team for getting the gear out on loan), I had the chance to hear their first foray into the more serious audiophile end of the market with their new CL1 Ceramic IEM, a hybrid DD/piezoelectric tweeter design encased in a fully ceramic housing and requiring more amplification than the average mobile phone or low-end DAP to get the most out of the included technology. While developing the dynamic driver for their new hybrid flagship, RHA discovered that with a little  tweaking, the dynamic driver could produce a very good full-range sound in its own right, hence the release of the younger (and cheaper) brother in the new range, the CL750. A high impedance/low sensitivity “budget” IEM seems a little unusual – if you want to see how it stacks up against its competitors, read on.
 

 
Tech specs
 
Driver: CL Ultra-wideband Dynamic driver
Sensitivity: 89dB
Impedance: 150 Ohms
Frequency range: 16 - 45,000 Hz
Max power: 50mW
Weight: 35g
Cable: 1.35m braided OFC
 

 
Unboxing
 
The CL750 certainly comes in some impressive packaging for a £99 product, the black box looking large and classy. A blown-up picture of the CL750 shell adorns the front, along with the ubiquitious “HiRes Audio” logo (note that 45kHz extension). The rear of the box carries an engineering blow-out of the internal workings of the driver, with a few notable points highlighted and a frequency chart nestling towards the bottom right. Opening the package, the inner box slides out to present the CL750 shells sat proudly in a thick foam insert, which pulls up to reveal RHA’s zippered carry case, which is about the size of a small wallet (without the money, sadly) and the instruction manuals and warranty details. The usual generous load-out of RHA and Comply tips are safely held inside the carry case, along with a metal cut-out to store the tips once they have been removed from their individually sealed packets. As this is a fixed-cable model, there aren’t any other notable accessories apart from a clothing clip. Overall, the impression is of a serious and costly piece of electronics rather than a “budget-conscious” option, so it’s definitely a good start.
 

 
Build quality and ergonomics
 
The CL750 is a solid feeling piece of gear, weighing in at a hefty 35 grams all told. This is due to the thicker than average braided cabling and the all-metal construction – the shell of the IEM is stainless steel, the main body of the IEM being made from one solid metal disc with an inner ear section that slopes inwards as it approaches the nozzle, looking like someone has attached an inverted funnel to the main housing. The cabling is fixed to the outer IEM shell with a solid see-through strain-relief, a thin portion of memory-plastic helping the cable to fall neatly behind each ear (the CL750s are designed for over-ear wear only).
 
In terms of comfort, the small puck shape and nicely designed inner-ear surfacing allows for a very ergonomic fit in my large ear canals, with the CL750 sliding solidly into place in my inner ear and the over-ear guides locking the IEM into place for extended listening sessions without any discomofort or readjustment required. The cabling is also worthy of mention, with a good combination of soft and supple outer sheath (in a transparent rubbery sheath over the visible oxygen-free copper wiring underneath) joining at the solid metal Y-split to form a tightly braided lower section, which behaves with zero microphonics and excellent softness. At first glance, the cable looks like an expensive after-market replacement, with only the fixed entry to the IEM shells giving it away – visually and functionally, it definitely screams quality.
 
The cable is terminated in a nice sold metal 3.5mm TRS jack (no microphone option on here – the power requirements to driver these IEMs properly would probably make that impossible in any case). The jack does appear to have a threaded section at the end to attach another adapter (6.3mm?), but nothing like this is included in the package so that is presumably designed for more “aftermarket” modification.
 

 
Sound quality
 
Test gear:
Hifiman Supermini / Megamini
RHA Dacamp L1 (balanced and unbalanced)
Fiio X7 (with AM2 module)
 
Test tracks (mainly 320kbps MP3 or FLAC/Tidal HiFi):
Nathaniel Rateliff & The Night Sweats – S.O.B. / Wasting Time
Blackberry Smoke – The Whipporwill (album)
Slash – Shadow Life / Bad Rain (my reference tracks for bass impact and attack, guitar “crunch”)
James Bay – The Chaos & The Calm
Sister Hazel – Hello, It’s Me (bass tone)
Chris Stapleton – Whiskey And You
Elvis – various
Leon Bridges – Coming Home (album)
Foy Vance – The Wild Swan
Daft Punk – Random Access Memories (album)
Aerosmith – The Definitive Aerosmith
Mavis Staples – Livin’ On A High Note
Twin Atlantic – The Great Divide / GLA
The Darkness – Permission To Land
Led Zeppelin – Mothership
Shawn Mullins – Soul’s Core
Sammy Hagar & The Circle – At Your Convenience (live album for audience sounds)
 

 
General impressions on the sound signature
 
The CL750 has a nicely balanced basic tuning through the bass and lower mid-range, with good sub-bass extension,  a decent amount of body and a nice tonality. Moving through the vocal ranges into the lower treble, it starts getting a little “hot” for my tastes, with a sharpness around the top end of the vocal ranges that can make some tracks a little harsh for extended listening. Despite this spike, the vocals and lower mids can sound a little recessed to me compared to the higher bass and treble volumes, leaving an overall impression of a “V” shaped sound in my head.  Once you are through the troublesome vocal region the harshness subsides, and the IEM actually extends well into the realm of canine enjoyment, topping out at the 45kHz mark according to the manufacturer’s promotional literature. Using RHA’s Dacamp L1 (also part of the touring gear), setting the treble reduction at the maximum permitted setting of -3dB does help tame the harshness somewhat, although this still sits firmly on the edge of enjoyable for me with some of my sibilance tester tracks, and in some cases remains more than I can handle for any extended listening. In terms of texture and detailing, the CL750 definitely has the chops to compete with (and exceed) a lot of the other IEMs that sit around this price range, so if you are a fan of a bright signature and can handle the extra heat RHA have decided to bake in to the default tuning, this may well be the IEM for you.
 
In order to tone down the treble enough to make this review possible/enjoyable, unless otherwise stated below, the following impressions are based on using the provided Comply Tx200 foam tips and a -3dB treble reduction through the Dacamp L1.
 

 
Highs
 
With a stated extension so high only dogs and animals using echolocation are interested in it (and only Mariah Carey records in it), you would imagine treble would be a major strength of the CL750. In the main, you would be right. Starting at the top, the treble has near limitless extension, holding clear and crisp all the way past my hearing range with a nice sense of energy and cutting edge to it.  It holds on to the screaming high notes of the dissonant guitar solos and intro in “Starlight” by Slash without any effort, laying out the higher guitar harmonics like a surgeon arranging their scalpels before a particularly tricky operation. Unfortunately, as you travel further down into the lower treble/high mid-range, the downside of this treble tuning rears its head, with a very punchy “spike” in proceedings that starts just as most singers clear their throat and only stops a few kHz further up the scale. This does have an unusual effect of the sound, crisping everything up nicely but actually losing some of the beautiful extension in the listener’s ear as the higher sounds can be dominated by the lower (and far louder) treble frequencies underneath it. Cymbals are a good example – there is a lovely crisp “tssk” sound to the initial hit, but they then seem to vanish into my ears without trace rather than splashing nicely into nothingness, usually overrun by whatever is going on underneath them. For my tastes, these are definitely an IEM I would need to EQ in order to enjoy properly, as the tuning is just a little too harsh for me to listen to on the types of music I enjoy. The flipside of that is that for tracks I am able to engage with, the crispness and crunch the IEM can bring in the higher registers is truly impressive.
 
It should be noted that micro-details in this frequency range are very well presented, with the clarity of the driver bringing a lot of fine detail out of the background into the main listening experience. Location cues (often driven by frequencies that sit above the usual human hearing range) are also easy to pick out due to the exemplary extension of the drivers.
 

 
Mids
 
Moving down into the mid-range, the texture that the CL Dynamic transducer can put out is pretty enjoyable, with male singers sounding raw and emotive, the fine nuances of their vocal inflections coming to the fore of the sound like you were running your ear over a piece of very expensive certificate paper or card. For voices like Otis Redding or Shawn Mullins, the sound is beautiful, with a gravelly undertone that highlights the imperfections in the voice and paradoxically highlights how well the driver makes this sound. Spinning up “Mama Told Me Not To Come” by Tom Jones and Stereophonics lead singer Kelly Jones, the junior Jones’ voice sounds like velvet gravel, and Tom’s soaring voice sounds just as magnificent as always. This sadly serves to highlight the sharpness present when the vocals reach just a bit higher, with the female backing singers and their higher-pitched lines teetering on the verge of harshness, and sounding a little thin in comparison (to be fair, an elephant could probably sound thin in comparison to Tom Jones, but you get my point).
 
Instruments fare better with the tuning on display, with a nice tonality on piano and guitar, and saxophone and other wind instruments sounding clear and clean. Electric guitar is crunchy and energetic, bordering on too aggressive without the -3dB EQ alteration. The sound isn’t massively thick, with a leaner note presentation and sharp edging to the sound that brings the sound back towards a more neutral or treble-centric overall sound rather than a warm and smooth style tuning. Acoustic guitar sounds very nice through these, with the strumming intro of “Mother Maria” by Slash and Beth Hart translating beautifully against the breathy sounds of Beth Hart singing the main refrain.
 
Flipping across to some more electronic fare, “Go” by The Chemical Brothers sounds surprisingly good, the rapped vocals coming through clearly and the swirling synths giving an appropriately euphoric backdrop to proceedings. “Feel The Love” also sounds very good, the Hammond organ refrain and the short, punchy synth riff kicking things off both build nicely into the main body of the song. John Newman’s vocals can sound a little quiet compared to the backing, however, making me want to pump the volume more to correct the “dip” in the V shape. To be fair, if you like more synthesiser based fare, the definition and edginess of the tuning will probably work very well for you here, with even the curtailed hi-hats adding rather than detracting from the presentation.
 

 
Bass
The bass on offer here is tight, deep and definitely north of neutral. It isn’t a basshead tuning by any stretch of the imagination, but the solidity of the bass and slight emphasis on the mid-bass region gives a nice warmth and substance to the lower reaches of the soundscape which contrasts with the more starkly neutral sound on offer higher up the scale. There is a nice presence and extension to the sub-bass without being overwhelming, and it is certainly more than enough to handle tracks like “Heaven“ by Emile Sande with ease, providing a nice low-level thrum and sense of physicality to go along with Sande’s crystal clear vocals. Playing the Random Access Memories album by Daft Punk is also a success, with the liquid basslines dropping right down to the floor of the tracks without losing much in the way of power or presence.
 
Trying my more traditional bass testers, “Bad Rain” by Slash is full of texture and definition, the tightness of the bass notes giving a muscular backing to the track, letting the listener feel the twang of the strings as they vibrate. “Hello, It’s Me” by Sister Hazel is also handled well, with the creamy bassline underpinning the song having just enough body to fill the lower end of the track like it should, while retaining a leanness and definition to the sound that again brings out the texture in the listener’s ear. It isn’t as gloriously smooth and velvety as some other IEMs I have heard, but the song doesn’t suffer due to the more dry and detailed interpretation. Dry is probably a good word to describe how I hear the bass on these IEMs, with the drivers presenting bags of detail and timbre in the lower end to define the sound, without an overwhelming amount of body or substance behind it. Comparing the CL750 to more heavyweight bass cannons like the ASG 2.5 or Campfire Vega, it is like a men’s health model in a room full of bodybuilders – plenty of strength and lean definition, but just lacking the additional “mass” to push it into the next category up. For people who aren’t after a bass bazooka, this tuning works very well, and is probably the strongest area of the signature for me.
 

 
Soundstage/separation
 
The CL750 gives a nice sense of location and placement of instruments, presenting in my head as a perfect sphere of sound that pushes just outside the limits of my head in all directions. Not a spectacular staging in terms of width, but it definitely has above average depth in this price bracket for me. The clarity of the driver also helps with separation, with multi-layered tracks like “Shelter Me” by Cinderella pulling the music into multiple distinct layers without too much effort. This isn’t the most clinical IEM on the market (as you would expect given the pricing) so don’t expect JH Angie/Campfire Vega levels of definition and staging, but for the price, this definitely exceeds expectations.
 

 
Tip choice
 
Tips are the standard RHA fare, with multiple dual-density silicon options, some dual flanged silicon and a smattering of Comply Tx tips. For my personal preference, the dual-density silicon fitted beautifully but were a tad on the bright side, so I found the best synergy with the Comply Tx-comfort series tips that are included. The “Waxguard” covering takes a little edge off the treble, still leaving it with plenty of crunch and bite but taking just enough off along to allow the treble reduction on the Dacamp to do the rest for my personal preferences and also allowing the best seal in my ears.
 

 
Power requirements / DAP synergy
 
At 150 Ohms and 89dB sensitivity, there is no getting around the fact that the CL750 needs amplification to sound its best. You can get an acceptable listening volume from a mobile phone (my LG G5 managed it at pretty much close to full volume output), but the design of the drivers demands that if you want to really enjoy what they bring to the table, extra juice is definitely a requirement.
Running the CL750s through my various sources, a surprisingly synergistic combination is provided by the new Hifiman Supermini, with the higher than usual voltage output of the tiny DAP bridging some of the power gap between standard phone/DAP outputs and the beefier Dacamp L1 to produce a good approximation of the sound form the L1. The little brother of the new Hifiman range (the Megamini) also does surprisingly well here too, requiring a good few more volume steps to reach the same output but again sounding a little fuller and less harsh than the G5, sitting between the phone and the Supermini.
 
Firing the CL750s straight from the Fiio X7 on high gain mode (AM2 “mid power” module), the sound surprisingly still felt a little thin, so this wasn’t an ideal match for me personally.
 

 
Overall conclusion
 
If the information I have read is correct, the CL750 was born out of a discovery the RHA engineering team made when looking at wideband drivers for their flagship hybrid IEM design. That rings true for me, as this IEM feels like something that has been discovered more than designed. It has bags of detail for the price range, but requires a small power pack to drive it. It has great texture and warmth in the lower end, but an unpleasant sharpness to some vocals that wouldn’t be out of place in a razor-blade factory. If you have the requisite gear to drive the wideband dynamic at the core of this IEM, you will likely not be looking at a fixed-cable £100 IEM to run off it. If you are looking for a quality IEM in the £100 price bracket, you are unlikely to get the most out of this piece of engineering with lower level (or less expensive) source gear. Certain things have been done extremely well (the ergonomic design, the beautiful cabling, the fantastic detail retrieval), but to me this feels more like an evolutionary stage in development than the final solution for this particular driver. If RHA can pour some water over the screaming heat in the high-mids/lower treble and allow the super-highs to really shine like they should, they could go somewhere with the technology. I am still a little confused what exact market they are going for, as selling an IEM for £100 that needs a £400 amp to really perform seems like a little bit of a disconnect in terms of the “use case”. This is one of the reasons for the low overall score I have given on this review - for me and my personal preferences, while I can appreciate some of the technicalities on display, the CL750 is too hot to be enjoyable for my ears, and a little too power hungry to appreciate properly without reaching for my “serious” gear, which reduces the likelihood I would use it as I would most likely reach for one of my more expensive in-ears at the same time. Major treble heads, people who don't suffer from the same particular sensitivity in the higher mids/low treble as I do and those who are happy stacking their DAPs might have a different experience, but as of right now, this is an IEM with plenty of potential but not quite the execution for my tastes.

 
Hello, Head-Fi! I am one of the members who was lucky enough to be selected to review the three newest products from RHA here in North America.  These products are the CL750, CL1 Ceramic, and the Dacamp L1.  Today you will be reading about the CL750.
 
Disclaimer: The CL750 were provided to me as a part of the North American Review Tour by RHA.  I have been given 10 days to listen to and then write a review where I will pass them along to the next reviewer.  My opinions written in this review are just that, mine.  They do not reflect RHA as a company.  I am receiving no monetary compensation for this review.
 
Introduction:
My first introduction to RHA was about a year ago, when they first released their first micro driver IEM, the s500i.  I found them a superb value at their price point, even though they had a pretty strong v-shaped sound and poor isolation.  I was also not too fond of their fit.  The CL750 is the more budget orientated IEM from RHA’s new CL line-up.  These use an ultra-wideband CL Dynamic transducer.  In short, this gives them a huge frequency range and superb detail.  The retail price of these IEM’s is 139.95 USD or 99£. This price slots it in a very competitive price range; the question is, does it hold-up to the competition? The short answer is yes, read below for more details!
 

 
Build Quality:
I am not going to spend large amounts of time talking about the packaging of the CL750 simply because many other Head-Fi members have already done a wonderful job with better pictures than I could take, so instead of rehashing past statements I will simply say the packaging is nicely done and well presented.  The CL750 also comes with a wealth of accessories; including a nice carrying case and plenty of different ear-tips to choose from.
The 303F stainless steel housing is nicely machined and is free of any rough or sharp edges.  The attached cable is, in my opinion, wonderful.  I personally think it is the nicest cable present on any IEM at this price point.  It lays flat without memory causing coils.  It is braided and is rather robust.  Microphonics on this cable is very slim, which is nice as this is usually a no go for me and other IEM’s as it is super annoying to me.  Consider it a pet peeve.  The only real improvement one could make to the cable would be making it detachable, but it is not a deal breaker especially with RHA’s 3-year warranty! That is an amazing warranty and I think speaks volumes about what RHA thinks of their own products.
 
One odd thing about this IEM is it does not come with a ¼ inch adapter.  I find this odd for two reasons: 1) It is advertised “for use with amplifiers” of which many have only a ¼ inch input such as my Grace Design m9XX.  2) It is threaded in an identical was as the CL1 Ceramic which does come with an adapter.  It seems like an odd omission from the generous amount of accessories for the product.  As of now, the threaded adapter is not available online for purchase either.  I am told that it will be available for purchase at some point however.  All is not lost, though, as a standard “clip-on” ¼ adapter will work just fine.  All of my threaded adapters are not compatible with the thread on this IEM so be wary if you choose to purchase the CL750.
 

 
Design and Comfort:
I personally love the design of the CL750.  The Aerophonic design of the chamber not only reduces distortion (so claimed by RHA) but also makes these IEM’s extremely comfortable.  The shape of the housing allows for minimal contact with the actual ear allowing these to simply disappear while wearing them.  Furthermore, the over ear loops are easily molded to the listener's likings and are thin and light enough not to bother someone who wears glasses, like me.  As far as comfort goes these earn top marks in my book.
 
Sound:
Notes: source material was through the Dacamp, m9XX, LG V10, and the Fiio X1i using a variety of lossless and non-lossless music files.  All of them were able to power the CL750 well.  For specific questions on each of the above source components please comment or PM me! Helps keep the review more on point!
 

 
Alright, so this is all fine and dandy that these look and feel great, but how do they sound? Short answer: extremely detailed with harshness at times.  These headphones have some serious treble present.  It is so present that it over-shadows the upper mids a bit on some tracks.  Luckily, it has a wonderfully done lower mid and bass region.  It really helps balance the overall tonality of this headphone giving it a quality V or U shaped sound signature.  Let us have a more detailed look!
 
The bass of the CL750 is wonderfully done.  It is just north of neutral to my ears, but not by much.  It has a good decay in the sub-bass region which means it will not take away detail in the track and gives a very lifelike presentation.  Pair this with the very articulate midbass and you have a headphone that does an awesome job at replicating male vocals.  I was very impressed with the replication of “I’ll be Standin’ Tall” by Josh Kelly.  He had a good fullness to his voice, but a nice crispy edge giving it a more realistic quality. 
The mids of these headphones are wonderfully detailed and are never impeded by the bass.  The only real downer about the mids is that they can sound slightly hollow in the upper regions and feel a little distant.  While a little distance can be nice as it gives a nice spatial orientation of the music, it can at times go a little too far, however.  This creates a presentation that feels as if the volume is too low, but turning it up will cause painful treble.  The mids were so close to perfect, but not quite there.
 
The treble on these is where I expect to see the most positive, and negative opinions.  As I stated right away these have some passionate treble.  The lower treble region has a large spike and then decreases in the upper frequencies.   It is well above neutral by a couple Db to my ears.  Now if you read my bio, you will know I do like a little treble sparkle in my headphones.  If they are too rolled off I tend to get bored with them or crave more detail.  That being said, these may easily be too much for many.
 
What do I think of the treble? I like it a lot actually.  While it is a little harsh at times, I would not call it sibilant unless it is on poor quality recordings or recordings that are naturally treble hot.  Generally speaking, it creates an amazing amount of detail and extension.  The extension is slightly robbed by the initial lower treble peak, but not too much to my ears.  If I were to make an improvement on the treble it would be to dial it back a touch in the low treble regions to give some vocals more room to breathe.  This would help open up those upper mids and reduce the harshness on some tracks.
The CL750 has a sound that is certainly V-shaped, and this may be a turn-off to many listeners who prefer a more neutral and warm sound signature.  I personally find the detail wonderful.  I was floored by the level of detail and the texture present when I was listening to “Thrace (Sunday morning Session).”  The recordings are filled with tons of detail and texturing that the CL750 handled with ease.  One thing you will not need to worry about with the CL750 is a congested sound, which is pretty impressive considering this is a single driver IEM.
 
Comply-Tips:
I wanted to write a special section about using the Comply tips.  For me, they really help out the CL750.  They give a better fit for my ears, especially my right ear which is oddly shaped.  This seal has a couple of effects on the sound of the CL750.  First off, it brings the midrange forward a bit giving it more depth.  It also takes some of the sharp treble out.  This I believe is in response to the wax-gaurd that is present on the comply tips.  If you get these and find the treble just a touch too hot, try out the Complys!
 
Comparisons:
I do not have a whole lot of IEM’s currently that match these in price, but I will make a few in case they apply to you.
 
SE215 (~100USD) vs. CL750 (140 USD): These are priced close enough, in my opinion, to be competitive.  The first thing I will lead with is that these are two very different headphones.  The SE215 is much warmer in signature with a decent mid-bass hump (as many Shure products usually do) and rolled off treble.  In contrast, the CL750 has a neutral bass and a treble emphasis.  The first thing you need to ask yourself if you are considering these two IEM’s is which musical taste best suits you?  That on its own could solve the dilemma for you!
 
If I had to pick a winner I would have to choose the CL750 for a few reasons.  The build is better, despite not having a removable cable. When it comes to value it could come down to personal preference.  The 215’s are easy to love with their laid back sound, but the CL750’s offer far more detail that I have come to love a great deal.   The fact is both offer an excellent value, but I would again give the victory to the CL750 as the sonic performance and detail are much better than the 215’s.  For audio quality, I am giving the nudge to the CL750.  It brings out far more detail and texture to the music that the se215 just cannot match.  I also find the CL750 noticeably more comfortable for long durations with a less microphonic cable.
 
CL750 (140 USD) vs. CL1 Ceramic (450 USD): Here comes a match-up I am sure many will be interested in.  The two new IEM’s from RHA pitted against each other.  I will not go into too much detail for the CL1 as I have a separate review for them, but I will give a few details for comparison's sake.
It is worth mentioning to start that the CL1 is about 3 times the cost of the CL750.  This means the CL1 is 3 times better than the CL750 right? False.  If I had to choose between them I would choose the CL750, in fact, I am likely going to purchase the CL750 as it has continued to impress me each day I listen to them.  The CL1 is even more treble hot than the CL750 which is just too much for me, and I even like some treble heat! Truly the only category I would give the victory to the CL1 would be in the build.  The ceramic housings are immaculate and look like nicely polished pebbles.  Everything else: sound, comfort, value, etc… goes to the CL750.  Not too shabby! (unless you are the Ceramic…)
 
One thing worth mentioning.  The above comparisons are for the CL1 without the Dacamp L1.  When you add that, and the balanced cable to the CL1 than it wins in every category easily.  The problem with that is now you are shelling out a cool 1000 USD.  At that price point, you enter a whole new realm of expectations in what you are getting.  It certainly does not sound 10 times better than the CL750, but it does sound incredible.  I go into more detail in my CL1 review so go there for more details!
 
Conclusion:
I am not going to try and draw conclusions for you, but simply sum up my experience with these over the past 10 days that I have had the privilege to listen to them. 
The CL750 is a wonderful IEM that should be on your shortlist if you are looking for an excellent, detail orientated headphone.  It offers wonderful clarity, especially at it's price point.  If you are sensitive to treble, you will want to pass on these as it will likely be too much for you.  I think these will appeal to a certain audience.  It does not try to be an IEM for everyone to love, instead, it picked one area to excel in, and does it very well in my opinion.  If that target lines up with your listening preferences then I am sure you will love these.  If it does not, well then take a pass and look elsewhere.
 

 
Thank you to RHA again for giving me the opportunity to listen to the CL750.  I have enjoyed every moment with these.  For those of you reading this review, thank you for taking your time to read my opinions and impressions of these new IEM’s from RHA.  If you have any questions regarding them let me know!
 
Happy Listening!

This 750 is part of a triple item tour organized by RHA, and I will be reviewing the CL750 connected to the RHA DACAMP 1 as they came in together, so it seems logical to use them together. I also did put the mojo into the euqation, just food for thought.
 
 
 

 
 

Packaging

 
The packing is straight forward, a pouch filled with different tips, and a booklet. That's about it.
 

Cable

The cable is 1.35 meter long, and is double braided OFC.The splitter portion has the Reid Heath signature, same as the MA750i I have, just presented classier, and lighter
 
One thing noticable is gone is the spring coil near the end of the 3.5mm jack, some see it good some don't, but for me, not good to go for that path.
 
Second is the screw on jack for the adapter, should have kept the universal compatibility IMO.

 

 

MA750i cable in comparison

In direct comparison, the MA750i cables are thicker and heavier, but less prone to tangle. 

 
 
You can see how they differ.

Listening Impression

Treble

The first thing I noticed when I plugged it in, is the immense amount of treble that the CL chimes out. It is literally ear piercing, and I did what i NEVER EVER did, I had to equalize down the treble at least -5dB on foobar just to be able to listen correctly. At first i thought it was the DACAMP kicking the treble way over board, but then I put in the mojo to test, it has lesser treble pitch, but still ear pitching. Hence, lastly, i HAD to use it with the x5ii to conclude if the IEM itself is the issue, and indeed it was, the treble was killing all over all my rigs. Way too much treble, not cool.Strike one!
 
MA750i is so much softer in the treble section and hence much more comfortable to listen to for long session. Mild treble but doesn't lose presence.
 

Mids

Now in direct comparison with the MA750i, the mids are more recessed on the CL. The MA gives a warm cozy vocals and with thickness, but on the CL, things are pushed back, and the vocals were thin. I'm starting to feel the urge not to write ahead, considering it's strike two on the CL ! Even on an a capella song, the vocals are so weak, and I did not understand WHY did they took the 750 model to the twisted abyss. I almost had a tear, knowing that the CL750 wasn't up to my expectation as the ALL NEW 750 generation. I felt it was not configured correctly to be out there.
 

Bass

This is somewhere that there is at least some compliment. Bass is punchy and short. Accurate and still preserved a little portion of the MA750i's bass performance, although with a lesser mass to it. I put on a bass heavy music, and the bass didnt punch my ears but still had that pop to it. Thats something

 

Conclusion

So, MA750i or CL750? that's what a lot of people had in mind, and I have to say, depending on mainly what audio quality you seek. IF you listen to a lot of music that doesn't perform well on treble sections, then this might help. Since the vocals are also relatively recessed, keep that in mind. For me, MA750i is still the general way to go, CL750 is out of the window for me, although the new iteration of the cable is lovely af, but that doesnt count anything if the drivers are the bad here. I'm keeping my MA750i TQVM.
 
Anyways still. I thank RHA for the chance, and as a fanboy, I hope they reiterate the 750 and be better than the MA version. Please, please, fix it and I will get it!

RHA CL750 Review
 
January 2017
 
 

 
Long intro… perceptions, patience and redemption! 
 
I will approach this in a different way to how I usually do as it is a relevant journey and road I went down although a long one before finally getting to review these so the Intro is quite epic proportions in length but felt it had to be told in relation to what I have heard and experienced from start to finish. So here is my story for Christmas…
 
I currently own the RHA T20 IEM which I had been looking at getting for a while and finally got them at a show recently after hearing them again and this is where I had my first opportunity to try out the new CL range they had on the table but it was towards the end of the day and had only limited time to try them out in the various different combinations available especially when taking into consideration wanting to try my current own gear with their respective offerings so was like a mad jumble of cables and equipment between my gear and their three new arrivals.
 
So after my session with them at the show had left me to want to try these for longer and took the opportunity to apply for the RHA tour in which at this stage I have to thank and acknowledge Glassmonkey and RHA for letting me have the chance to review these in the comfort of my own home for 10 days. 
So to start with usually it will be one item to review over several days but this was three bits of kit over 10 days which was a challenge in itself but life is full of challenges and this would be a fun and interesting one.
 
Going back to the show when I first heard them I have to say and going to be honest here as I could quite easily erase this part from my memory but it wasn’t the most positive experience I had at their table trying these for the first time and started off with the CL750’s which thought be best natural order of things before making way to the new flagship CL1 and their new Dacamp so first of all tried it with my Chord Hugo just to see how it would fair and know the Hugo can be fussy with anything that is bright.
 

 
 
 
I was surprised when I plugged it in it was sounding strained with quite a harsh treble (more so than normal RHA treble experience of say T20 and I am one of those sensitive to anything too bright or hot with the top end)  but this had the life sucked from the mids with hardly no bass and my Hugo was struggling to drive them and had been at a volume I had not seen before so after talking to the RHA guys I tried another set of 750’s they had and same thing.
 
So I thought nothing of it and moved onto the CL1s through my Hugo only to find a similar thing so thought this was a bit strange so tried my Vorzuge Pure with the Hugo which is the tool I use when I have any IEM or Headphone that is to bright or cannot be driven properly by the Hugo usually does the trick but again even with Hugo at a high volume or used even line out my to my Vorzuge Pureii+ was even challenged by them even in high gain and they never struggle with anything so checked all my connections as I knew this did not sound quite right.
 
All connections seemed secure so turned off everything and turned it back on and tried again, this time the 750’s sounded a bit better than before and turns out it was the Chord Hugo must of freaked out and had a funny turn and have not had it before then or since so went about listening to the 750’s and have to say although it was an improvement still took a bit for my Hugo to power them and it was still too much treble ended sharp sound with not right balance across the frequency’s to me and it still was not right so added the Pure again and although better than just with Hugo thought it did not sound right. 
 
At his point I’m thinking after trying the CL1’s again with same results even though friendlier on the ear than the 750’s at this point thought well might as well give the Dacamp a go at this stage as I thought it has to be the magic ingredient as they have made it to go with each other like the Two Ronnie’s belonged together to do comedy for four decades. 
 
 
 
So plug the CL750’s into the Dacamp and it again seemed a slight improvement but was still far away from what I had expected and still was coming across all treble with no bass at all, same mirror image occurred with the CL1’s after on the Dacamp and the experience left me perplexed as my audition with the Dacamp was good and enjoyed it so knew it was the both IEM’s not right to my ear. I did relay this back to the RHA team at the time and they did say the final production models where going to have a bit more bass but just thought to myself even so the treble needs to be tamed a bit more than I heard there. 
 
I mean I’m border line with the T20 treble sometimes like I am with my Sony 7520’s can sometimes throw up going beyond the comfort of what treble extension can do to been uncontrolled and sounding what to most 17 year olds must sound like an ASBO alarm outside a off licence.  But the overall balance was not there and was puzzled why even my Hugo and Pure struggled with them.  My Sony ZX1 Walkman was a no go but felt I had to try that from the start just to know for confirmation to myself my ZX1 has all the grunt of a two stroke scooter trying to chase a 750cc Suzuki down the road. 
 
SO I  walked away thinking the Dacamp would sound good with my JH16’s but already had the very under-rated Vorzuge Pure amp and a Hugo. 
 
And I must admit I was having second thoughts like a runaway bride about even doing this tour review knowing this and then a couple of people reporting hearing a too much treble and nothing else and feeling disappointed but sometimes we all need to have the full fact’s in front of us to know the full picture and I decided to tell myself stick with it and if they are that bad still you will have to  possibly be first review where I have to give a low rating as to be honest what reviews I’ve done so far I have been lucky with them all been pretty good sounding products on the whole plus ones where I have applied for a tour have gone for ones that have interested me personally and know probably sounded half decent to start with or heard them before anyway but this was a bit daunting it could be my first negative reviews and after buying a T20 recently which I enjoyed with caveats and all thought would be a shame to start with it been RHA gear.
 
So upon receiving these from Takeanidea I was in intrepidation and suspense how this would all pan out.  So I will now start my review the normal order of merit so if you want to find out how they sounded please fast forward down to the Sound Impressions header to find out.
 
For now I will talk about packaging, build and design functionality….
 
Unboxing
 
The packaging from the outset even for the CL750’s seem to have had a direction of lets make this look like a flagship type of feel to fit in with the new Cl range as a whole although this out of the three new RHA products is the lease luxury packaging it is above average taking into account this is only a £99 product.
 
So once the bottom card flap is opened the inner box slides out to present the 750’s sitting in a nice laser cut foam protection tray housing and once lifted out the rest like carry case, manual and accessories are all located in two split dividers in the bottom of the box. 
The Cl750 comes with the following accessories.
 

1. Protector case
2. Dual density Silicone ear tips (6 pairs)
3. Double flange ear tips (2 pairs)
4. Comply TSX-200 foam ear tips (3 pairs)
5. Clothing clip

 
Build, Design & Fitment…
 
 
The build of the Cl750 is the normal high standard with its stainless steel aerophinic design that will be so familiar to how the MA750 looks. This are not going to break when you drop them like acrylic shell housings and they do not feel too heavy either, there is enough weight though to know they are made from steel and have a feel of quality about them which is extended in the form of the cable which is a braided oxygen free cable which has high quality 3.5 plug termination which I did not notice any microphonics during my time with them. 
 
They look like time has been taking on them and look quite cool with the durable PTE which shows the copper cable and the actual cable entry to the shells look to have a durable flexible soft plastic moulding to protect the cable but cannot feel they missed a trick as I know this is a very competitively priced IEM for what is trying to achieve but cannot see why they didn’t make them detachable still like the CL1 so these could also go balanced to go into the Dacamp L1 as would of made it more tempting for the CL750 customer to maybe jump to the CL1 also knowing it already had the balanced cable included and not to mention it would have been interesting to of heard this balanced after hearing the CL1 in balanced mode (but I’m not going to spoil that here, you will have to check out the CL1 review for that!)
Apart from maybe not having detachable cable the design and build is the usual RHA standards.
 
Fitment for me personally was good but did have to fiddle to initially get it past the Tragus part of the ear but once it got around that all though feeling a little uncomfortable doing so it locked in place and I actually used large Comply’s which I do not usually do as I’m usually a medium size but as the design of the metal shell once locked in place did not budge it was ideal for the Comply’s to expand without moving the ear piece anywhere it shouldn’t off so for me it was quite a good fit but can see maybe this design not been so good for others but will also be a trial and error with tips also in conjunction with balance of fit and sound.
 
For me I could listen for long periods with these in and have had my fair share of issues with Comply’s with certain IEMS recently which I think also is very reliant upon the design of the shell in conjunction with the tips.
 
Warning: these will feel cold on a proper winter’s day when inserting if outside out and about!
Solution is for RHA to make a portable rechargeable hairdryer for them or IEM dryer in this case!
Imagine that in the accessories section!?
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
Sound Impressions…
 
 
The following impressions was done with:
 
Chord Hugo
Vorzuge Pureii+ amp
Sony ZX1 Walkman direct H/P out, and as source to Hugo/ Pure combo
HiFIMAN Supermini direct H/P out
HP X360 Spectre WIN10 laptop via Hugo/ Pure via Vertere DFI USB cable
Music files used: WAV, FLAC, DSD 256
 
 

 
 
I will start with tips in general as this is quite an important disclaimer before I go on about the ramblings of what I heard in my ten days with them is I tried some different tips but as I have found out in general of late is I preferred the Comply tips overall for the sound approach to silicones for the ability for slightly better isolation and better bass response as well as slightly taming the highs a little even though I found silicones okay in the end with these I personally preferred the Comply’s despite them giving me other headaches in general and been far from perfect with different IEM’s I have tried in the last couple of months.
 
This reminds me of once hearing a pair of Heir IEMS (cannot remember the model now for the life of me, maybe Tzar350?) which I tried a few years ago which had a same type of sound which was a clean linear sound which was quite revealing that really needed an amp to go with them but were very much treble happy as a few of Heirs earlier models I heard were capable of but the difference here is the 750’s do not have so much of that piercing treble like the Heirs had and more importantly what I heard at the show a couple of months ago from the CL750’s that were on that table which was a shock but at the same time a pleasant and surprising shock.  It was not just the treble but also the mids where there now with an actual bass presence that could be distinguished and have to say from what I heard at that show two months before hand was quite a relief but knew I still had a long road ahead with listening to them to see if they actually did have potential to sound good.
 
I started off playing safe by using them with the Dacamp L1 as my way of thinking was if it still sounds not right with the Dacamp L1 what chance did I have but luckily for me the more songs that went by I thought well… I’m still here listening so can’t be too bad.
What I was finding was a good clean and crisp linear sounding IEM which had reasonable tight lower bass response that was packing a bit of punch on impact in general at the same time from the RHA’s own Dacamp but not a nasty hump in any particular frequency and had good control with no distortion.
 
The neutral and clean no nonsense sound coming from these was actually very reminiscent to a not so well known or heard Ortofon EQ8 (have to credit RocketRon for introducing me to those IEMS) which have a good level of detail without been over articulate with enough musicality but without the aid of an amp the Eq8 was dead in the water as it would sound half its potential self with hardly no lower bass response when in fact with the right amp that could deliver the EQ8’s came to life with a really low controlled hard hitting bass that just left you hooked to the sound. 
 
The CL750’s are very much like that just with not quite as much low end bass as the EQ8’s but the CL750’s are far from shy with the amp powering them. 
 

 
 
So this is not the first IEM designed to really be paired with an amp but to get the best from them it will need a good amp section like the Dacamp to get the 750’s to sing but for the difference here with the CL750’s compared to the old Heirs I heard a few years ago and the later EQ8’s from last year or so is the CL750 comes in at least £200 less than them and is very intriguing to think these are only £99 which is about only £20 more than the acclaimed MHA750’s which I unfortunately have not really heard so will not be able to do that comparison for those MHA750 fans out there.
 
But the more I spent time with the CL750’s I was finding I was enjoying these with all sorts of musical genres and it did not really phase the 750’s from what I heard.
 
The treble (no not trouble!) with RHA is some might find it too much and after my long intro about that and owning a pair of T20’s even with flat filter on they have a slight tendency to lean towards presenting the treble with more accentuation and at times with some tracks can find it approaching border line as I do have a treble sensitivity to a degree despite my older age of losing a few DB’s which is natural at my age (which is early 40’s by the way without giving that away)
 
I had this issue with a pair of Sony headphones a few years back which I really loved in the Z1000’s but the treble was to sharp and piercing despite loving the rest of the sound signature and frequency range till good old Jude at the London Head-fi show a few years ago enlightened me to the non EU version in the Japan made version of them which was essentially same headphone.
 
The Sony’s labelled them as the 7520’s which had better bass presence (as the Z1K also lacked there a bit)  and the hot treble had been tamed so got them on his advice and true to life he was right (not that I doubted golden ears for a second of course) although the 7520’s still once in a while could exhibit the border line a treble getting a bit much with some tracks like I find with the RHA T20’s so after hearing the CL750’s at that show like I did thought here we go but something has definitely happened in those two months.
I do not know what exactly but these are noting like I heard at the show by the distance from the earth to the moon and (same went for CL1’s in my other review on them) and the treble was now not over piercing yet had an amazing amount of extension still which the 750’s are capable of but without feeling like Sharon Stone is ramming an ice pick into your head! It had plenty of headroom but with an accurate and controlled delivery which aided the tonally accurate side of the treble range.
 
It is a very clean and un-coloured with the treble to the ears and tonally sounds real enough and this area is probably the only area that sounds a bit raised in terms of frequency tuning to probably get those extension ranges in the shiny metal bits on the drums like symbols & hi-hats to have a real tone to the impact and trailing edge of the notes with a nice shimmer with good decay.
 
I have to say I was still a bit flummoxed and perplexed at this stage I was not hearing an ear bleeding top end like I did at the show two months before.
 
But what is a good treble which RHA like to or seem to spend a lot of time on to other companies in trying to perfect without getting the mid’s and bass right.
 

 
 
Well, the mids are not recessed much thus it does give a more hall effect sound with the sound staging but the clean spacey sound of the 750’s make it easy to hear mid information retrieval individually and there is a nice cohesion between the highs and lows to the mid-range which is why there is never any real nasty surprises listening with them as you always know what you are going to get with them once you put them on.
 
 Of course I mean that in a positive way, not a negative as it just handles any music thrown at it with a consistency of clean controlled accurate hard hitting dose of equal measures in everything it does.
 
Vocals I really liked as they were just clear and projected considering they sounded a tad distant but had good grain to details with an artist singing so you locked onto them first then the music flowed up to the front door of your ears like a natural wave of sounds and always was just easy breeze to hear the lead vocalist with enough detail in their notes with a sense of openness around the artist singing although maybe male vocals in general just edged female singers I am a sucker for female vocalist and very fussy with the reproduction of a lady’s lungs but the RHA was very adaptable and passed the test for me and to be fair was not far behind how it portrayed male vocals anyway.
 
The 750’s extension is good and having the mids tidy and informative enough with details which I think are above it’s £99 price label to what I’ve heard from others in this price point recently as most IEMS at this price will try to put a nice enough balanced fun musical signature together but fine details or space for it to breath won’t be there, this is totally different with this CL750 and is trying to bring that reference type neutral sound in at an affordable price I felt that has detail yet musical enough still without been too fun nor at same time not ultra-analytical.  Cannot feel again I am in some parts here describing the EQ8’s in many ways which I think is a testimony really to the 750 perhaps.  
 
I was liking the string details and rawness the 750’s clean mids gave to guitar works and had a natural low mid bass feel with bass strings.  Pianos sounded good with enough tonal quality and depth but just was felt a bit short in detail and clarity which from experience of using with other gear think this was more the dac on the L1 as opposed to the Cl750 as I then heard pianos sound much more focused, finer string notes in detail with each key and less fuzzy with the Hugo-Pure combo. 
 
Dance music good dynamics with the 750’s which had  enough thump to groove to with the mid bass been well controlled and sub bass having enough rumble impact without been over flooded into the mid information in the following milliseconds of following notes so made it easy to follow the beats and rhythm at the same time with the 750’s.
 
But if the Bass cannot match the above average treble extension and neutral clean mids then it all falls down a bit and I heard not a lot of sub bass is the kind way of putting this at the show from them, made the T20’s sound like DR. Beats bass levels mercifully and thankfully from out of nowhere the bass frequency is there in the production model I have for review going deep enough in a natural response so is not over cooked so some die hard bass fans might not find it enough but it gives a more linear low bass end but is done with a tight and quick response making things never sound muddy which complimented the upper bass frequency’s and aligned nicely to always hear that critical area of details from the mids which still had a good amount of impact in the lower mids to help with the rhythmic sections of songs. 
 
So the bass will never be a flood of sub bass end rumbles that cover the entire soundstage of these IEMS rather they deliver in accordance with the rest of the signature which is a clean and concise not messing around I will tell you like it is with the efficiency of a German built car.
 
If Scotland built any cars let alone well-built ones I would of course be referring to one of the RHA nationalities built cars, but only if they did build cars like RHA build IEM’s? (…Hmmm, Maybe Ferrari a fast sounding car with that high revving top end engine tuning sound they have!?)
 

 
 
The soundstage I have to admit did not jump out at me or had an extra sense of width but is far from closed in and has enough there to have that sense of space in width and depth of field for it all to work with the way this sound signature as there is a sense of space around notes enough to point them out with great precision which some IEM in this price point suffer from sometimes.
 
Even during busier periods it does not lose control with it’s very good amount of headroom with a good enough amp  but the only flip side to this is some might find the sound a bit cold or hard in the nature of the way the 750’s roll giving a stripped feel sound with been flatter with  non-colourization of notes but it delivers music without putting icing and strawberries on top and gets to the core of the music without dressing it up unnecessarily.
 
Some I might feel especially if used with silicone tips also may find it a bit too much on the treble still if you are sensitive to it but like I have said already from someone that has experienced this myself in the past found it acceptable although a poor recording especially if to bright in that area will then make the CL750’s a bit hard to listen to even with comply tips on but for most part with normal to good recordings I am mainly able to forgot about this been ever a potential issue at all as I was enjoying the music too much without it distracting me.   
 
On subject of recordings with the Dacamp L1 it really made a difference with DSD files and just had a bit more solidity on top with more body in detail with notes as well it becoming clear what the extension in the treble RHA like to achieve becomes a bit clearer with a good DSD recording and notes in general have a more precise tonal quality to them so the CL750’s scale well with file formats.
 
With other gear other than RHA’s own DACamp….
 
For those who want the IEM only for whatever reason may be how does this perform with other gear?
 
From experience with my gear starting with the Hugo, as I already have touched upon the Hugo can be fussy with pairing with anything that shows likeable treble ranges and I found this was one of those it was just a tad too much the both of them together which is equally down to the 750 as well as the Hugo as one thing I have found and have to declare from my findings with RHA gear just as the Hugo is the CL range certainly is fussy with what it is paired with so this may also be an on-going agenda for debates on RHA treble findings as I admit with Hugo it was not a good match in this area.
 
As well as Hugo seeming not to have the right voltage swing keep control so put the Pure with it and this 750 becomes tame enough again I can listen to it on the high end and sounded as good although different to the Dacamp and it really suited the Pureii+ as it also delivers a clean hard hitting sound with it helping the slightly recessed lower mids come out a little bit more than usual but is just tuned a little more enthusiastically than the CL750 in general but is a very good combination as the sense of overall balance Is in line with the 750’s signature. 
 
Tried again just with my Sony ZX1 Walkman and is better at driving it than at the show which is weird but not much more and had to deselect the sound enhancement on the Sony which releases more power output which made it listenable.
If at home in quite surroundings despite this been good isolation it makes the difference as it is just enough to hear but is still not enough for the 750’s to be driven properly with the authority needed to get the best from them to deliver dynamics and height they can produce with good amping. 
 
Next up was my HIFIMAN SuperMini which is apparently designed to power headphones up to 600ohm but myself did not find from this as they were just okay with 300 ohm set of Sennheiser open backs  I tried.
 
But the Supermini is still great with IEM’s really and have to say they powered the CL750’s okay but only had three or four steps left on the digital volume so if out and about again could be a different issue with them.
 
They did sound fine out of the Supermini which had a slightly warmer signature although the treble did show a tendency to sound a bit too hot at times  but the CL750 reproduced the detail of the SuperMini quite well in the mids with nearly all genres apart from classical or female vocals with this combination. So it was a mixed bag with the Supermini that maybe would stop me from using this pairing in the long run.
 
 
 
Conclusion
 
My overall thoughts apart from great relief how these did not sound anything like I had heard these at the show as to be honest I was a bit worried it would be my first review where I would effectively have to put a product down like a vet putting down a rabbit which would have been cruel to be kind scenario as before this CL range come to the fore I really do like the way they have an eye for detail in the build and design with even the smallest of details and the packaging is always above standard affair and love how they pretty much the only ones they pay a lot of attention on universals to things like the ear hook design that will also last long term and not just short term so their offerings up till now had been good value if you liked their signature up till now but the new range had to offer more than just good presentation looks and build. 
 
It had to have substance in the sound department and my biggest fear after hearing them at the show was they were going more treble hot than ever with very recessed mids and no bass, strange balance but seen people shot themselves in the foot with a double barrel shotgun before!
 
But once I received these for review everything had changed quite drastically sound wise which I cannot fathom why or how it can change so much in two months even if a prototype at the show but it was a sound I was comfortable with as I found no issues with treble at all like I had at the show and it became a very balanced clean transparent cohesive neutral sounding IEM that had above average extension without losing its head and a nice tight sub bass to compliment the linear mids which gave a good amount of detail retrieval and reproduction with vocal timbre although a little distant still for lead vocals. 
 
Only word of cation which should probably come with most RHA gear to present for those sensitive to treble they may still be too much for your ears to cope with and it can still be border line for me at times depending on equipment and recording pairing can bring it to the fore more but it is more settled with it mothership Dacamp L1 pairing a bit more to start with before been able to use the tone control features to EQ balance it to your taste. 
 
For the money if you are after a straight forward no nonsense IEM that is not coloured, veiled or warm and can give a good amount of clean detail with good extension and precise clear presentation at this level but still sound musical and dynamic enough at the same time but do not mind amping to get a the best out of them then for only £99 this are almost astonishing and well worth checking these out.
 

[size=24.57px]INTRODUCTION[/size]

I was first introduced to RHA (or Reid Heath Acoustics) during a review tour for the RHA T10i, and later the RHA T20. I was very impressed with the build and fit on both earphones, but less impressed with the T10i signature (too bassy IMO), and pleasantly surprised with their T20 – which I still regard as a very good earphone in its price range. So when their new CL range was announced late in 2016, I was very keen to review, and especially so when there had been a little bit of controversy around early impressions of their earphones. Call me nosy – but when this happens, I just really need to get a listen. I also wanted to measure the CL range, as its easier to really discover truth when you can compare what you hear with what you are able to measure. So join me in a small voyage of discovery as we put the CL750 through its paces.

ABOUT RHA
Reid Heath Acoustics (RHA) is a Scottish based headphone company. Their core values (from their on-line presence) are described as follows:
“We stand for true-to-life audio reproduction and lasting quality. With these values at our core, we work to deliver the most accurate, comfortable and unobtrusive listening experience possible. Every RHA product combines high quality materials, precision engineering and our fundamental commitment to design.”

Their current product catalogues ranges from the budget oriented MA350 (~ USD 30) to the current flagship CL1 (~ USD 450). The CL750 sits at $140 – which is in a nicely mid-tier pricing bracket.

In the last couple of weeks I have spent as much time as possible listening to the CL750, CL1 and also their L1 DAC/amp. Sadly I don't have a chance to directly compare to the original T10i or T20 (they were part of a tour), but toward the end of the review I have compared the CL750 to some other IEMs in similar price brackets.

In the time I've spent with the CL750, I’d estimate that I’ve logged around 20 hours actual listening time.
RHA on Facebook
RHA Website

DISCLAIMER
I was provided the RHA CL750 (as part of a tour) from RHA. I am in no way affiliated with RHA - and this review is my subjective opinion of the CL750. The tour unit was returned at completion of the review. I'd like to especially thank Iain and Niketa for their brilliant communication and allowing me to be part of this.

PREAMBLE - 'ABOUT ME'. (or a base-line for interpreting my thoughts and bias)
For the purposes of this review - I used the RHA CL750 mostly with my iPhone SE as transport to RHA's L1 DAC/amp but also from most other sources I had at my disposal – including my trusty X3ii/E17K combo. I'm a little on the fence with the CL750 and amplification at this stage. At 150 ohms and 89 dB sensitivity, it really will need extra amplification (especially with weaker sources), however even my iPhone SE at 60% volume was able to drive them fairly respectably – more on that later. In the time I have spent with the CL750, I have noticed no change to the overall sonic presentation (burn-in), but am aware that I am becoming more used to the signature as I use them more often (brain burn-in).

This is a purely subjective review - my gear, my ears, and my experience. Please take it all with a grain of salt - especially if it does not match your own experience.

THE REVIEW

PACKAGING AND ACCESSORIES
The RHA CL750 arrived in a reasonably large, but attractive black retail box measuring 143 x 200 x 74mm. There is a lot of information on the packaging (which is IMO very well laid out) – including:

1. Front face = picture of the CL750, Sony Hi-Res logo, and instruction that an amplifier would be required (nice touch)
2. Rear = information on design, materials and frequency
3. Sides = information on warranty (3 year!) and contents
4. Bottom = CL750 specifications

Opening the bottom flap allows you to slide out the internal tray which reveals the CL750 nestled in its foam cut-out. Below this are compartments for carry case, tips, tray, manual, and for the cable to sit.
The carry case is a largish padded zippered case measuring approximately 130mm x 85mm x 25-30mm (at its deepest point & depending what you include when packed) – so while it’s not pants pocket friendly, it does pocket very well inside a light jacket. It is well padded, with generous inner pockets and a mesh/canvas-like outer covering. The case is large enough to hold the tips in their steel display tray.

The tip selection is generous, and along with the storage tray includes 2 pairs of dual flange silicone, 6 pairs of single flange silicone, and 3 pairs of Comply Tsx-200 foam tips. The mounting tray is stainless steel and from past experience, works really well as a storage medium. There is also a small plastic shirt clip. As I was first recipient on tour, I've shown pictures of both how the tips come, and how they are mounted on the tray. Fellow members in the tour – feel free to use these photos if you wish.
The manual is multilingual, very informative and includes a frequency graph (which incidentally corresponds very closely with my own – nice to know my rig is recording things nicely).

TECHNICAL SPECIFICATIONS
(From RHA)

FREQUENCY GRAPH
The graphs below are generated using the Vibro Veritas coupler and ARTA software. Ken Ball (ALO/Campfire) graciously provided me with measurement data which I have used to recalibrate my Veritas so that it mimics an IEC 711 measurement standard (Ken uses two separate BK ear simulators, we measured the same set of IEMs, and I built my calibration curve from shared data). I do not claim that this data is 100% accurate, but it is very consistent, and is as close as I can get to the IEC 711 standard on my budget.

The graphs are provided merely as a point of discussion, and later in the review I've included comparisons to other IEMs for similar reference. I will note that my graphs pretty much very reflect similar measurements shown by RHA.
What I’m hearing from the CL750:

1. Quite natural sounding mid-bass with a slight hump, and pretty good extension (some natural roll-off into sub-bass). Quite good extension to sub-bass though.
2. Relatively flattish lower mid-range, maybe the slightest recession or distance in vocals, but it is minor, and adds to the impression of staging size
3. Upper mid-range has a slow rise in the presence area (2 kHz) and gives a clear and clean vocal presence.
4. There is quite a sharp and clear lower treble which may be too hot for some (it borders on being too sharp for me – there is a definite emphasis between 5-7 kHz, so if you are sensitive to brightness, could be problematic
5. Upper treble extension is very good
6. Overall it is a V/U shaped monitor with a bight upper end, but because the bass is well defined and tuned, there is a nicely cohesive sense of balance. It is about as hot in the lower treble as I'd want to go though (any more would cause me issues, and I generally like a slightly brighter signature).

One thing to note is the almost perfect matching of left and right channels. You really don't get much better than this – bravo RHA.


BUILD QUALITY / DESIGN

External
The RHA CL750 has a two piece injection moulded stainless steel body which is circular in shape, with a nozzle which is centered, and rises to a peak (basically I'd call the IEM “volcano” shaped for want of a better descriptor). It measures 14mm in diameter and 16mm from the rear casing to the nozzle tip. The right outer face has the letters RHA nicely engraved, while the left has the model number CL750. There is a single port/vent for the dynamic driver at the bottom edge of each ear-piece. The surfaces are all nicely rounded with no apparent sharp edges when worn.
The nozzle proper is only 3-4mm in length, but in reality because of the shape of the housing extends closer to 8-9mm. It measures just over 5mm in diameter and takes a standard Comply Tx200 tip. There is a generous and well designed lip which securely holds the ear-tips.

The ear guides are permanently attached to the housing with excellent strain relief. The are preformed – basically to hang loosely over your ear when worn, and are very comfortable and natural to use.

The cable
The cable is permanently fixed to the CL750 (which I really don't mind at this price point). It is OFC and consists of twisted pairs from earpiece to y-split, which are then combined to larger twisted pairs between y-split and jack. The twisted pairs are covered with a TPE outer coating, and the whole cable is very flexible, and only slightly microphonic when worn over ear. The slight noise disappears entirely when cinched. The Y split location is very low on my chest (only about 2 inches above my belly-button) – which feels strange, and I would have listed as a con if not for the excellent inclusion of a very good slide-able cinch to keep everything in place. The y-split is made of stainless and has the serial number engraved in it, as well Lewis Heath's (RHA’s Product Director) signature. It is light enough not to notice, but heavy enough to keep the ear-loops nicely in place.
The cable terminates in a straight 3.5mm gold plated jack. The casing is stainless steel and it has a premium look and feel. The jack has a screw in section at the base – allowing an adaptor to be applied (although one is not included). This extra spacing also makes the plug smart-phone case friendly (if your device has sufficient power).

All points of the cable have excellent strain relief. Overall the cable has excellent build quality throughout, and I couldn't really see the need for swapping it with anything else – at this price point anyway.

Internals
The review wouldn't be complete without mentioning what RHA has achieved with the internals of the CL750. To start with, the choice of the stainless steel body – both material and shape – was to transfer the sound waves directly from driver to ear (completely in phase) with no distortion at any volume. The use of the stainless steel rather than thermoplastic is mainly to reduce internal resonance – but also gives other benefits such as durability and longevity.

When RHA were developing the dynamic driver for pairing with the ceramic plate on the CL1, they found that by adding a second layer to the diaphragm, they could alter both the bass and mid-range / lower treble frequencies. This addition became the CL1. But the omission of the extra layer (unaltered driver) cost less, was sonically very good, and very clean – so this became the basis of the CL750. The driver has a high impedance because of the high flux density of the voice coil array (which is just a mere six microns) – and it is this which allows the very high precision, detail and accuracy.

FIT / COMFORT / ISOLATION
I have one ear canal slightly different to the other one (my right is very slightly smaller) - so I tend to find that usually single silicon flanges don't fit overly well. I initially tried the included large silicone tips, and I was unable to maintain a constant seal. I then switched to the included Comply Tsx200s and got an immediate seal and fantastic comfort and isolation.
The CL750 also fits Ostry tuning tips, Spin-fits, Spiral Dots and Sony Isolation / Trinity Kombi tips perfectly. Whilst I stuck with the Comply for this review – I did find that the other fore-mentioned tips all gave reasonably good seals.

Although RHA do not use an angled nozzle, I personally find the overall fit to be fantastic. Comfort for me is excellent – the CL750 is one of those designs which simply disappear when worn. They sit well within my outer ear (inside the external ear cavity – between tragus and anti-tragus), and are extremely easy to sleep in.
Isolation with the CL750 is better than average for me (not quite near Shure’s or Alclair’s almost perfect isolation – but very effective), and they would be good enough for public transport (despite the vent).

There has been no driver flex present.

SOUND QUALITY
The following is what I hear from the RHA CL750. YMMV – and probably will – as my tastes are likely different to yours (read the preamble I gave earlier for a baseline). Most of the testing at this point (unless otherwise stated) was done with my FiiO X5ii + A5 as source, and the included Comply tips. The reason I chose to go with the X5ii + A5 combo was merely to ensure that there was more than enough power on tap for the CL750.

For the record – on most tracks, the volume level on the A5 was around 9 o'clock on the pot (using low gain) which was giving me an average SPL around 65-75 dB. Tracks used were across a variety of genres – and can be viewed in this list http://www.head-fi.org/a/brookos-test-tracks.

Frequency Relativity

1. Sub-bass – pretty well extended, with only minor roll-off (very good in fact for a dynamic driver) and there is a little rumble present, but it is not over done at all. Sub-bass shows a peak to the curve at around 50 Hz and is very slightly raised compared to mid-bass, but the overall bass presentation would be the best I have heard from RHA so far.
2. Mid-bass – on par compared to sub-bass (graph shows slightly less mid-bass than sub-bass, but it sounds extremely natural). So it is in effect a very gentle mid-bass bump, but also very evenly distributed. The result is a very natural sounding bass response – and indeed sounds more natural than the CL1 to me. There is no noticeable bleed into the mid-range. Both mid and sub-bass are elevated compared to lower mid-range.
3. Lower mid-range – recessed compared to bass and very recessed compared to upper mid-range and lower treble. Its not all bad though – just a little distant – and I've found myself upping the volume with some tracks (which brings some issues with lower treble). Because of the elevated lower treble, and recessed lower mid-range, I have found that male vocals can sound a little thin. My go-to Pearl Jam – lacked body on the vocals.
4. Upper mid-range – elevated compared to lower mid-range, and it is slow rise from lower mid-range to the first peak at about 3.5 kHz. The result is a clean and clear vocal range, with good presence to lend a sense of euphony to female vocals. The upper mid-range on the CL750 is one of the best qualities of this IEM. The upper mid-range would be perfectly balanced with the mid-bass if the peaks had been slightly lower, and if the lower treble had less presence.
5. Lower treble – elevated (quite a bit). There is a peak at between 5-6 kHz, and it is considerably higher than the upper-mid peak. Then there is a drop to more manageable levels with another small peak at 9-10 kHz. The problem with the lower treble is the size of the peaks +15 dB above the recessed mid-range at 1 kHz. So while you do get a lot of clarity, there is also a sharpness / sizzle which seems to be always present. For me, even tracks like Pearl Jams “Elderly Woman Behind the Counter in a Small Town” becomes slightly sibilant (and it is not a sibilant track). The other thing which disappears is cymbal decay – its there, but lost in the sizzle of the cymbal hit. Its a shame really as in trying for extreme clarity in this region, they've lost their overall sense of balance.
6. Upper treble – nicely extended with good air. A lot is lost though in the intensity of the lower treble.

Resolution / Detail / Clarity

1. Good with micro detail, and able to resolve most finer details well.
2. Cymbal hits have good presence, but decay is lost due to intensity of the lower treble peak at 5-6 kHz.
3. A very clean and clear monitor with good resolution but overall portrayal is unnaturally on the bright side.

Sound-stage, Imaging

1. Extremely precise directional queues, and just on the periphery of my head space with binaural tracks – so good sense of width and depth.
2. Spherically presented stage – with very good presentation of both width and depth
3. Compelling sense of immersion with the applause section of “Dante's Prayer” - but it did sound unnaturally hot compared to what I am used to. I then went to try “Let it Rain”, but the sibilance (it is normally present in the track anyway) was heightened to a point which made it unlistenable for any length of time. This could be solved by EQ.

Strengths

1. Very good overall bass response and one of the most balanced releases from RHA I've heard - in respect to overall bass and mid-range.
2. Quiet good overall with male vocals, better with female vocals
3. Good with dynamic music – and able to show wonderful contrast between bass and upper mid-range (e.g. Cello and Violin). Cello sounded utterly believable with the CL750.
4. Very good with acoustic music and gives strings good sense of realism and tone when plucked, and nice edge to electric guitar when strummed.
5. Very good with female vocals, lending a slight air of euphony and sweetness.

Weaknesses

1. Lower treble is over-done relative to the rest of the frequency range. Anyone with a sensitivity toward brightness, or a preference to a richer mellower tonality should avoid.
2. Vocal fundamentals can tend to sound a little recessed
3. Not good at high volumes – lower treble gets pretty unpleasant. This is not helped by the vocal recession (which actually prompts trying to turn the CL750 up)

AMPLIFICATION REQUIREMENTS
The CL750 with its lower sensitivity and higher impedance really needs to be amplified. But it can sound pretty good straight from a smart-phone of DAP as long as they aren't power limited. From my iPhone SE with general pop/rock songs, around 50-60% volume was sufficient to get to a pretty good listening level.

With the X3ii I needed 60-70/120 (low gain) depending on the track, and it was similar on the X5ii. The X5iii was around 55-65. So while amplification is recommended, if you have a DAP or source which is powerful enough, you should net some pretty good results. To be honest I didn't notice a lot of difference between the different amplified and unamplified sources I tried – mainly tonality with the amp sections. One of my favourite combos was the IMS HVA and iPhone SE as transport. The other was the X3ii and E17K – see below for reasons.

EQUALISATION
You've probably already guessed at what I think needs changing on the CL750. Yep – tame those treble peaks and it should be a very nice sounding IEM. For starters, I went with the very basic – used my iPhone SE by itself, and engaged the treble reduction. Some immediate relief, but it also curbed some of the mid-range, so not the ideal.

Up next was the iPhone SE as transport, and RHA's own L1. Take the treble down to -3, and the CL750 became a very good sounding IEM with the glare greatly reduced. Next I used my go-to, the X3ii and E17K – and this time simply engaging -4 treble (the E17K was on 24/60 volume). The result was (to my ears) absolutely sublime – and if this was the default signature, I'd even consider buying a CL750. Really stunning. Finally with the new X5iii, using EQ I dropped the 8 kHz and 4 kHz sliders down – again a big difference for the better – although I think that overall the best difference was with the X3ii and E17K combo.

COMPARISONS
Normally I like to try and compare the reviewed IEM with something in its own price bracket – but because the CL750 was pretty polarising with its treble, this time I've gone with a bit of a range. With the comparisons, I first volume matched with a 1 kHz test tone and SPL meter. I had a fast switch set-up in place with a splitter and volume attenuator for the volume matching. This section is very subjective, as it is sighted, the change between IEMs took about 5-10 seconds, and I knew exactly which one I was listening to. But it is my honest thoughts on where the CL750 sits for my own personal tastes. Source used was the E17K / X3ii combo – with no EQ.

CL750 ($140) vs Dunu Titan 5 ($140)

Both have similarly good build, fit, accessories, and as you can see both are practically same price. Personally I like the overall fit and comfort of the CL750 just a little more. The Titan 5 has removable cables – but they are proprietary, so I don't regard that as necessarily a gain. The CL750 is of course much harder to drive – the Titan 5 is easily driven out of practically any device.

Sonically both are on the V shaped side of neutral with beautiful sounding bass, an elevated upper mid-range, and elevated peak in the lower treble. Where they differ though is the extent of that upper treble peak. Personally I find the Titan 5 to be easier to listen to out of the box – although with EQ, the CL750 is possibly the better sounding IEM as far as ultimate resolution goes.

CL750 ($140) vs MEE P1 ($200)
I chose this comparison – simply because the price is not too dissimilar, and they do share some commonalities. They both have excellent build, fit and comfort, although this time the MEE P1 this time does have the better cabling and overall accessories.

Both have similar bass, and bass to mid-range ratios, but again the difference is in the upper mid-range and lower treble. Where the P1 has exceptional balance in these areas, the CL750 is emphasised – giving it the over brightness and heat which has the potential to become an issue with many recordings. The P1 has very good extension through to the early upper treble, but does not over-emphasise it. Overall the P1 is a better IEM (as it should be) and for default sonic signature pulls ahead by quite a margin.

CL750 ($140) vs CL1 Ceramic ($450)
I won't go into a lot of detail with this comparison. Both are from RHA, and although the CL1 is their flagship, there are a number of areas which I consider the CL750 to be the better earphone. Build is very good on both – but I must confess that I'm not a fan of the proprietary MMCX cable connection system (more on that in the CL1 review). Otherwise, the CL1 has the ceramic casing, the additional driver membrane layer, and the more ergonomic fit – but they mean nothing if the overall experience is not enhanced by the use of these.

Tonally, while both are V shaped, the CL1 is more so – exhibiting too much sub- bass and way too much lower treble to be enjoyable without a heavy dose of EQ (and definitely not for a flagship). The CL1 is too hot and makes practically every track I've listened to sibilant and harsh to the point of removing enjoyment. Next to the CL1, the CL750 is a blindingly good bargain.

CL750 ($140) vs Rhapsodio RTi1 ($600-800)
This one is here simply to show the strengths of the CL750, and also because at first listen, I was immediately reminded of the RTi1. Both have very good build. The RTi1 has the better cabling system. Both are comfortable – but I'd actually take the overall fit of the CL750 over the RTi1 – for me personally it fits better.

Sonically the two are very similar. Both with EQ sound amazing. The difference of course is that after EQ there is still a large price difference. Anyone enjoying the Rhapsodio RTi1 should consider taking the CL750 for a spin. They are similar enough on sonic ability (CL750 has a bit more extension) – but the price difference shows just how well the CL750 is capable of performing.

RHA CL750 - SUMMARY

I love it when you see companies pushing the boundaries. Sometimes they get it spectacularly right, sometimes spectacularly wrong, and sometimes they have almost everything right – so that their next release will be the perfect one. Ultimately I think RHA are definitely on the right track with the CL750 – they have almost everything right, but have a bit of a speed-bump with the final tuning (my personal view).

As far as build quality goes – it is top notch. No flaws or obvious design faults. Fit and comfort both excellent. RHA really knows how to ace this area of design. Accessories are great – especially in this price range.

Sonically the CL750 has the basis of an excellently tuned IEM. There is very good and very well balanced bass response – which would be ideally matched to the mid-range if the upper mid-range was reduced a bit, and the lower treble reduced by more. With EQ (toning down the upper end) it is a truly fantastic IEM, and if RHA release a mark ii – I hope that they take this critique on board, as at this point (with a tuning change) it would be an easy 5 star recommendation.

Normally this would be a 3.5 star rating – but considering overall build, price-point, and the fact that it really does sound brilliant after EQ, I would still recommend it, and it gets a 4 (80%) from me. However the recommendation is for people who like a brighter tonality, and who are not treble sensitive.

Once again thanks to RHA for including me as part of the tour.

FINAL THOUGHTS
I was trying to (throughout the whole review) think of what the CL750 reminded me of. It clicked this afternoon. I owned (and loved) a pair of modified Grado SR325i (wood cups, bass hole adjusted, changed cable and head-band). For a long time they were my pride and joy – my hobby. Tyll measured a pair of 325s and graphed their frequency response. Ignore the compensated response and just look at the raw (grey data). Note the similarities. For any Grado 325 lovers out there – this is what the CL750 sounds like – just with better extension. Thought it might be interesting.

Greetings Head-fi!
 
Earlier this year RHA released three new products; the CL750, the CL1, and the Dacamp L1 portable dac and amplifier. The CL750 is the most wallet-friendly of the three, and the one we're checking out today.
 
The CL750 was heavily inspired by the venerable MA750. While it retains the same general Aerophonic, stainless steel shell design, the cable has been updated to a braided, high conductivity oxygen-free copper version. Their drivers have an impedance of 150 ohms and are intended for pairing with an amplifier to get the best performance possible. With a frequency range of 16-45,000Hz giving them Hi-Res certification from the Japan Audio Society, the CL750 is setting itself up to provide quite the auditory experience. Do they meet expectations? Let's find out.
 
Disclaimer:
 
The CL750 was sent along with the CL1 and Dacamp L1 as part of a review tour set up by RHA through Head-fi.org. Once my time was up up, these three little beasties were send to the next reviewer in line. There is no financial incentive in reviewing these products. The opinions and thoughts within this review re my own and no representative of RHA any any other entity. Thank you RHA for giving me the opportunity to check them out!
 
When I started writing this review and went to double-check on the price, seeing the MSRP of £99.95 / $139.95, my comments took on new meaning. Keep in mind that the majority of this review was written with a $200 price tag in mind. Spoiler: I think this earphone is an awesome value at their MSRP and would still be a good value even at $200.
 

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Packaging and Accessories:
 
My only experience with RHA prior to this was reviewing the S500i, their very successful first foray into the world of micro-drivers. Despite being an entry level product you were presented with a quality unboxing experience and provided a solid set of high quality accessories. The CL750 takes things up a notch.
 
The cardboard box you are presented with initially is fairly large, measuring in at approximately 8"x6"x3". The front contains a high-gloss image of the CL750's housing, some logos, and notification that they are intended to be used with amplifiers. The sides highlight the included accessories, that they use flexible earhooks, and also include a very generous 3-year warranty. The rear of the package puts emphasis on some of the more important features and provides a simplified frequency chart. On the bottom you find the specs;
 
 
 
Opening the package and sliding out the inner box reveals the CL750 nestled in a laser-cut foam sheet. Removing this reveals the cable tucked under a small box holding the manual, all neatly wrapped and set within it's own space. Above sits the carrying case which holds all the spare tips. As with their new flagship the CL1, the CL750's overall accessory package is excellent. Included is:
 
- 6 pairs of RHA's familiar dual density silicone tips
- 2 pairs of bi-flange silicone tips
- 3 pairs of Comply Tsx-200 foam tips
- steel tip holder
- cable clip
- zipper, semi-hard carrying case
 
Overall the CL750's unboxing experience is very thorough and the accessory kit quite generous. I'd be shocked if someone has issues finding a tip that fits given the variety of sizes and styles included.
 

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Build and Comfort:
 
Everything I've come across from RHA has been extremely well built, and the CL750 is no exception. The steel housings are well-machined, and fit and finish from the straight jack to the tip of the earpiece nozzles is flawless. My only criticism is the material used for the strain relief at the jack. I know this heat-shrink style of relief is common, especially among more premium earphones and custom cables, but it looks unfinished and a tad cheap.
 
The cable is a braided OFC piece and is wonderful. It doesn't hold memory and is very flexible. The molded rubber ear guides also work very well in keeping the weight off your ears and cable secure, unlike the spring-loaded option used on the flagship CL1. The CL750's ear guide implementation is superior I feel, even if it lacks the premium look and feel.
 
The CL750 was a very comfortable earphone for me. With the pre-installed medium tips, there was no struggle to get a consistent seal, and once in place the earphone was set and didn't move about. There were no hotspots caused by sharp edges or odd shapes, simply because there are no odd shapes or sharp edges. The Aerophonic design kept everything but the nozzle away from my ear.
 
Overall the CL750 is amazing well-built, putting most earphones in it's price range and above to shame. The cable, materials, and fit and finish are all top notch. That they are very comfortable is icing on the cake.
 

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Sound:
 
Amping: With their sensitivity rated at 89dB and impedance at 150 ohms, you would expect the CL750 to be challenging to drive. Well, to no surprise they are. Just as the advertising would lead you to believe, the CL750 needs an amplifier to reach their full potential. From my HTC One M8 they were pretty lifeless, just like the flagship CL1. With an amp, such as the Dacamp L1, they came alive bringing forth an energetic and detailed sound.
 
Tips: Given the limited time available for listening, I stuck with the stock tips and spent a little bit of time with some Comply foams. The foams softened the treble and sucked a bit of life from the CL750, so I stuck with medium single flange silicone.
 
When the CL1, Dacamp L1 and CL750 arrived, I immediately took the CL750 for a spin. I spend most of my time listening to budget and mid-fi products and figured it would be more in my wheelhouse. To my pleasant surprise the CL750 came across to my ears as similar to JVC's once popular FRD/FXD series of carbon-nanotube micro-driver earphones, but with a level of quality and refinement they can't come close to offering. Performance was more akin to the Echobox Finder X1, but not quite up to that level.
 
With that said, the CL750 is a fun, v-shaped earphone with a touch of warmth and prominent, lean, and detailed treble. It comes across to my ears as a baby CL1 and gives you a taste of what to expect from RHA's new flagship.
 
Like the CL1, the CL750's treble is quite prominent. Here it is dialed back to a more manageable level. The detail and clarity on offer is outstanding and quite similar to some of the best single dynamic earphones I've come across in the price range, the Blue Ever Blue Model 1200EX and Echobox Finder X1. The 1200EX achieves this with a more balanced sound than the others, however. Treble on the CL750 is extremely revealing of recording flaws, so I recommend lossless or high quality files at least.
 
The CL750's midrange takes a bit of a backseat, but not to the extent of the CL1. Vocals are clear and smooth with excellent detail. The touch of warmth really helps male vocals stand out. Background vocals are not lost in the mix and guitars retain a strong showing with excellent crunch and grit when required.
 
The CL750's low end was less prominent than I was expecting and is tastefully boosted. The mid-/sub-bass balanced is nicely done with equal presence given to both. I would prefer a little more emphasis on that low end rumble, but what's there should satisfy most. The presentation is fairly quick and punchy overall, with lots of texture.
 
Soundstage size feels about on par with the CL1 but lacks the laser-like instrument separation accuracy. I felt imaging and separation were behind my price leader, the 1200EX, lacking the openness and movement of that particular earphone, but overall they're still above average and better than most.
 
Overall the CL750 brings listeners a well tuned v-shaped sound. If you're wanting something with a prominent mid-range or prefer a less energetic treble presentation, these might not be for you, but this comes across to me as a fun signature that many would enjoy. It's too bad an amp is needed since that will limit their audience.
 

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Final Thoughts:
 
The RHA CL750 are a value leader, without a doubt. The build and material quality, and the quality of construction are not something you generally find at this price. The accessory kit is generous and about as complete as it gets. The quality of sound produced by their single dynamic driver easily stacks up well against other earphones under $200. This is a great example of a v-shaped signature done right.
 
Taking all this into consideration the CL750 is a very well-rounded product that would make for a smart purchase, especially if you are someone that buys only one earphone at a time. Just make sure you have a decent amp and quality sound files handy, as they'll be needed to get the most of of the CL750.
 
Thanks for reading, and thanks again to RHA for including me on the tour!
 
- B9Scrambler
 

Introduction

 

With thanks to my esteemed colleague and front page superstar @glassmonkey for fronting this review spectacular.  3 cheers also go out to Iain and the rest of the RHA team for filling up my dining room table for 10 days.

I didn’t think 10 days would be long enough to get through all this kit; my partner disagreed. She seemed to think 2 days was more than ample and seemed to glare at all those boxes. Especially when I wasn’t looking. I was able to rise above all that, and when push came to shove, I found pointing at my ears and shrugging my shoulders conveyed all the necessary feedback. The moment in history is now gone, the table is back with it’s rightful owner. Barring this, the last of my 3 reviews, we have all moved on.



 
The CL750 from RHA is the more affordable version of the CL1 Ceramic. It uses some of the materials that go into the flagship but retains the standard look of the stainless steel range. The CL750s need just as much juice to drive them as their big brother, but not so much out of the wallet. The price differential is 250 pounds.   The technology that has gone into the driver is a single ultra wideband ceramic design. In contrast the flagship CL1 has a hybrid CL dynamic and ceramic plate driver setup. The sensitivity 89 dB, impedance 150 ohms and frequency response 16 hZ to 45 kHz are identical.  That is where the similarities end. 

 

 
Having packed the CL1 back into it’s box ready for @FortisFlyer75 it was high time I got to grips with the CL750 and I made the most of my remaining time hooked up to such things as my Chord Mojo and the DL1 Dacamp. The Ibasso DX100

 
and an Audio Opus#2



 
took some of the duties.  The CL750 does not look on the face of it to be sensitive enough to be powered by a smartphone. I had to try of course. I got good results from my Moto G4 with the volume at about 80%, they sounded balanced enough to me. I didn’t feel like the CL750s were going to leap out of my ears and walk off in disgust. They didn’t mind a bit of Deezer. Not at all.

 
I normally go for sound quality as my next part of the review. I’m going to take some advice from a fellow headfier and put that all nearer the end. I hope that’ll make people read the review as a whole and get a fuller picture of all the attributes so they don’t miss something. That snippet might be a dealbreaker otherwise overlooked. 

Build

There have been some compromises made in designing the appearance of the CL750. They retain the stainless steel housings of earlier RHA designs. The shell is stainless steel so is strong and looks modern. I do not like the shape of the housings. They do fit snug enough into the ear. The small footprint of the shell leaves a large gap at the top and bottom of the ear. There are much more ergonomic shells out there on universals which follow the general contours of custom in ears.


 
These have a better fit and need a lot less fiddling around with to get the right degree of isolation and comfort. Stainless steel has no give and can pull on the inner parts of the ear as one tries for the last % of sound quality. Not all is a disaster here; there is a good deal of isolation present in the CL750s due to how close to the ear canal these can be pushed. 



 
 

The cable is not detachable. It has a twisted braid design. There is a memory wire part to enable an easy fit around the ears. Detachable cables are not the be all and end all for me. With some of the more difficult designs it is quite hard to get those cables in securely. The more this happens the faster we sprint toward problems in the future. No detachable cables – no heartache. If we had easy push pull connections – and I have several such ones, things are altogether much easier. The advantage of a decent detachable; I can adapt my IEMs to suit my needs. If I want a Bluetooth cable I can take my phones out for a run, if I go for a walk I can put hands free on. If I want to hit it hard and chill - silver core could be in the offing; even balanced, as per the CL1.



 
Microphonics and isolation all score well with the RHA. The memory wire is not as posh or a long as it’s more expensive counterpart but does the job well enough to eliminate any problems holding the weight of the cables away from the ear canal. Sound leakage is no issue as the housings seem sealed completely. 

The terminations are all top notch, the 6mm adapter a great fit into the mini jack. Included is a zippable carry case and plenty of tips, including comply foams. I achieved good enough results using a small silicon tip in my left and a medium in my right ear that I didn’t indulge in further tip rolling. 

Sound quality

Bass

The bass had enough linearity and punch to keep me entertained with my rock music and immersed with my acoustic stuff. The bass did not have the grunt of the CL1s nor the accuracy of my Sony XBA4ips.

 
It didn’t have the depth in the upper bass of my oBravo Erib 2as. It did manage to get close to all of them. That is a fine performance for under 100 pounds.

Mids

Vocals were forward and easy to follow, male vocals slightly less so than the fairer sex. As on the lower FR I feel here the 750 is offering nothing unduly unpleasant. The dynamics and separation from the XBA4ip and Erib2a

 
were a more refined offering but both cost significantly more.

Treble

This is where I was expecting trouble from RHA. I have a sensitivity to the standard RHA signature and expected the forward edgy steeliness commonly found in this part of the market. The extension of the CL1 will undoubtedly cause some differing views. Whilst I personally liked hearing all that energy, not everyone will react in the same positive manner.  The DL1 had a treble energy to it that worked beautifully with the CL1 but I struggled with for other IEMs. Including the CL750. Put the CL750 with the Chord Mojo and the problem disappeared. The CL750s I am pleased to say, are not treble hot. They extend well into the higher ranges but pull back before any damage is done.  The soundstage is wide enough to follow individual parts or simply to relax and enjoy.



 

Conclusion

I raved about the CL1s , whinged about the DL1 and feel I have been suitably glowing about the CL750. It does not need the DL1 to get the best from it. In fact, these IEMs can produce good results from a smartphone. Show them a decent bit of power and you have yourself a bargain. The CL750s didn’t do anything particularly fantastic to make them stand out from the crowd. Arguably such a sound signature could end up being one that produces a keeper. The build is designed for life.  In today’s throwaway world that is a bold statement to make. Farewell RHA til the next time. It was good to finish on a high. Especially as the high was not too grating.