RHA CL2 Planar in-ear

I received the RHA CL2 as part of the North American review tour.  Getting to try out earphones at this price point is a treat for me as it is well above my normal budget.  Having said that, with the price point of the CL2, expectations are high.   I have tried to stay out of the discussions surrounding this earphone until such time as I had a chance to listen to it.  I will try and evaluate the CL2 as fairly as possible and words here are mine alone.  I was compensated in no way, nor do I have any financial interest in RHA or any of its affiliates.   After my time with the CL2, they were sent to the next tour reviewer.


Unboxing / Packaging / Accessories:

I almost always debate the need for this section as most unboxing experiences are pretty uniform.  In this case, there is little doubt that the kit needs an unboxing and accessories discussion.   The kit starts out as a book-box design.  Once the outer cover is removed the book unfolds into 3 sections.


The left most section contains a 3.5mm single ended cable (copper) and a 2.5mm balanced cable (silver plate) in the upper compartments and a selection of tips on a carry card in the lower.  The card has 7 silicone tips and 2 styles of foams on-board.   The middle section of the box has a foam board with cutouts for the earpieces themselves and the Bluetooth cable and the right most compartment has the flight adapter, USB Cable, a soft case, and a folding travel case for the cables and accessories.  A clip for the wired cables is also tucked neatly amongst the parts (with this being a tour kit, I am not 100% certain where it is supposed to be amongst the other goodies).   The kit provided with the CL2 is as complete as any I have ever seen at any price point.  Short of providing the DAP and source material, they put everything in the box and organized it very well to boot.







The earpieces themselves are a comma shape with a slightly blunted nose made by injection molding zirconium ceramics.  Shells are made in two parts, (outer and inner) and while surfaces are glass smooth the seam between the outer shell and inner shell is easily seen and felt with a fingernail.  The outer shell has RHA stamped into the housing and is tastefully understated while the inner shell has CL2 and either L or R in a circle.  The right earpiece also has a red ring circling the mmcx connector for identification purposes.  Nozzles are made of stainless steel and protrude from the lead edge of the comma with a slightly forward rake and are of what I would call normal length.  they are not overly long, nor do they seem particularly shallow.   I like the grills on the nozzles as they are one of those little custom touches that probably does little for sound but does everything for the eye when looking at them.   The pronounced lip on the nozzle should make tip retention all but guaranteed as well.





The mmcx connectors are well implemented as they neither were overly brutal to manipulate as some recent examples have been, nor were they loose enough to worry about drop-outs, or disconnections due to movement during use as has also been a problem with others.   While I am still of the opinion that perhaps the bi-pin connector is more trustworthy, RHA does a good job of showing that mmcx connectors can be well implemented.

Fit is very easy and I found no problems with size, but having said that, I did find a need to use a larger tip than normal as one side (R) wanted to seat considerably deeper than the left and initially caused me some problems.   This is likely to be a function of ear shape and others may not find it to be an issue.  For me, the CL2 is thin enough that it can rotate at the mid point so the nose seats deeper in the ear while the rear pushes slightly farther out than level.    I haven’t found myself lamenting an in-ear that was too thin, but in this case it just might be true that a bit of extra girth might well prevent that.  Tightening the chin slider and carefully fitting the earhooks also helped.


Drivers in the CL2 are listed as a 10mm diameter 16μm thickness planar driver with a nominal impedance of 15Ω and a sensitivity of 89dB.    This puts the CL2 in the middle ground where it can be driven by a phone but it definitely benefits from a bit of extra power due to the low sensitivity.  (This is not an uncommon theme in planar drivers).    That doesn’t sound impressive, until you realize that the driver was developed in-house by RHA and represents the first time a planar driver has been fully enclosed in an in-ear design.  Audeze and a few others have released what are called planar in-ears but in truth the driver is much larger and sits outside the ear with only the sound bores sitting in the ear.  The CL2 fits as comfortably in the ear as any standard dynamic of BA design.    I look forward to seeing RHA continue to advance this state of the art in planar miniaturization.



The cables bear some discussion of their own.  Most IEMS don’t come with this complete a set of cables even at this price point and all three of the cables are well done.   First up is the standard 3.5mm TRS terminated single ended cable.  The Jack is a straight model with a polished stainless housing and about a 1cm clear plastic strain relief at the exit.  The cable is oxygen free copper in a two wire twist design up the splitter and single wire straight design above it.  (Yes I know there are two wires on each side above the split, but to look at the cable you wouldn’t know that).   The splitter is also brushed stainless with the RHA logo on one side and a serial number on the other.  Strain relief on the lower side of the splitter matches that on the jack while the upper side has shorter 2mm soft plastic strain reliefs to avoid interfering with the chin slider.  The slider is clear rubber and requires good effort to move but not so much so as to worry one about the amount of stress being placed on the cable to move it.  The cable terminates at the earpieces with a weighted earhook with a metal spring inside to help it retain shape followed by an MMCX connector housed in clear plastic.   Honestly, the last 3 inches of cable do not appear to be of the same grade or quality as the rest of the cable and the earhook is probably my least favorite part of this package as it is unnecessarily large and cumbersome.  Every time I put the CL2 with this cable (or the 2.5 for that matter), I had to readjust as they had loosened up and the earhooks wanted to interfere with my glasses.  Were I to purchase this IEM, I would request an un-weighted version or simply replace the cable.





Second up is the 2.5mm balanced TRRS terminated cable which shares most features with the 3.5mm except it is silver plated copper rather than pure copper.  Otherwise, construction is the same and repeating the earlier comments seems unwarranted.





The third cable in the bunch is the Bluetooth model.    I kind of expected the CL2 to fall apart when we moved to this cable as I expected the cable to have trouble keeping up with the power requirements of a planar and Bluetooth having trouble keeping up with providing a good enough signal to really give the drivers something to work with.  I was partially right.     The band itself is of fairly typical behind the neck design which I am not a huge fan of but does distribute battery weight evenly and it was more comfortable than expected.  One issue I did have was the exit of the cables from the body of the band has no strain relief and while fairly thick, it was already showing some signs of use on the tour.  Under less stressful use, this may be a non-event, but I would prefer a more durable design.  At least the terminations this time are standard earhooks with mmcx connectors and fit my ear better and interfere with my glasses less than the wired offerings.


On the functionality side, when first turned on a voice greeting announces how much battery life the unit has left which is a nice touch and seemed fairly accurate although I did find if I turned the unit on and off repeatedly I would occasionally get a different value (usually within 15% of the other, but it did vary).    To pair the device, a long press of the power button puts it into the correct mode and the LED will blink the typical red/blue pattern to let you know.  I had no issues with pairing with any DAP, phone, tablet, or laptop I tried the CL2 with.

Controls are on the right side cable and are very similar to other RHA offerings.  The barrel is steel as used in the other cables with a rubber strip that covers the 3 buttons.    The three buttons are Volume down/back, play/pause, and volume up/forward as you travel up the barrel.   Its a fairly simple design, but it works reasonably well.   The microphone on the reverse however was in a perfect position to rub on my shirt collar and made it less than stellar for use on phone calls. (Who uses a $1000 iem for phone calls anyway?  I should be so lucky).

Battery life.  Ok, so battery life is almost always over-stated and unfortunately I found that to be the case with the CL2 as well.   RHA’s website lists a 12 hour battery life which I found to be optimistic at best.  I did find that I could use the cable for nearly an entire work-day (8.5 hours with a few breaks) without having to stop and recharge it, but would need to recharge before using it again.  Still this represents extremely good battery life when the weight of the cable is considered, but I do think RHA may have fibbed just a touch on this part.



Having already alluded to the need to roll tips a bit to get the fit I needed, I can say that the CL2 came with quite a selection of tips and I found a set I could be happy with in the kit without looking outside.     Tips included are two sets (SML) of dual density single flange silicone.  (This is the way you get around saying Spin-fit if you didn’t license the name).  Also included in the kit are small and large double flanged silicone tips (which while usually my least favorite turned out to be exactly what I am using to do the sound notes on the CL2) as well as a couple pairs of medium sized T400 Comply foams.   I have some Large T400s in my kit but thought they did little for the CL2 and thus stuck with the large double flange due to the positioning issue I previously mentioned.

Sound:  (Sound Notes done with Large double flanged Silicone tips)

I had hoped the T-series tuning filters would fit the CL2 but it does not currently offer this.  (Maybe CL3 will?)



Sub-bass on the CL2 is quite good in both quantity and quality.  I was particularly impressed by how tight the sub-bass was and how well articulated it is.  Walking bass lines are clearly rendered with no slop and no lingering decay.    Mid-bass is in near equal proportion to the sub-bass with only a slight push forward while maintaining the same level of control.  Overall, the CL2 is impressive in its ability to deliver a basshead worthy performance without feeling like a one trick pony that is all bass and nothing else.   If you have friends that say “Bass doesn’t have details” let them try the CL2 and then ask them if they still believe that.   These do a good job of making music below 250Hz and not just noises.



This is the place where I normally talk about the degree of mid-bass bleed and the amount of warmth  the bass contributes to the overall signature, problem is on the CL2 it has none that I could detect.  The bass stays where it should and transition into the mids is nearly flawless with no perceptible bleed to discuss.  The mids do show a push forward that starts around the 1kHz mark that plateaus around the 2.5kHz mark and stays at that plateau until a bit over the 5kHz mark as it exits the lower treble.  This is the one place I struggled with defining the CL2.  At times, that push forward of the mids gave vocals a nice intimate feeling while at others it could be unnatural and overly aggressive.   The more I tried to find a commonality to what sounded good or bad, the more I returned to two factors.   The first factor is source.  The CL2 is better when paired to the Fiio X7 (ESS) that tends to be a bit dry and clinical in the mids than to the  Opus #1S (CL 43198s) that tends to be a slightly warm anyway.   Same for the AK70Mk2 – it sounded better when paired to the xDSD and used as a transport only instead of using the internal DAC on the AK.   The second factor is source material.  I found consistently that the higher the compression and less the dynamic range of a track, the worse the CL2 handled it.   Seems the loudness wars have taken their toll on a lot of tracks and the CL2 does a bang up job of identifying them.  Unfortunately for me, my collection is not devoid of those and I found several tracks that were just plain unpleasant as a result.

Once you know the limitations of the CL2 and pair it appropriately, the mids can be impressive.  Detail retrieval is very good and micro-detail is better than most.  Again the attack and decay speed prevent any slop and percussion in particular is well rendered and very natural sounding.   Vocal realism is on par with the best I have heard in an in-ear although female vocals seem a bit closer to the listener than male due to the slight push of the upper-mids/lower treble.



As previously mentioned, the lower treble sits on a plateau forward of the rest of the signature mildly and then begins to fall off as it moves into the true treble.  Those expecting the granularity of typical planar treble will be markedly disappointed as while the treble is not quite as detailed as the lower registers, it still manages good extension without going too far forward and reasonable detail without becoming harsh.  Cymbals are well rendered and don’t have the metallic clicky sound often associated with planar drivers, and enough air and sparkle exist to really contribute to an immense feeling of space.


Soundstage / Imaging:

This is the thing I find the most out of character of the CL2 of all its attributes.  To remind people, we are discussing a planar driver (not known for gigantic stage in general), in a closed shell (another bad sign) with maybe 5ml worth of space inside the shell, and out of this tiny cavity with rock solid (literally) walls, we expect to hear a stage that is anything other than minuscule?   Well, yes actually we do.   The CL2 delivers in spades as stage is both wide and deep and has some height.

Imaging is very good which is helped by above average instrument separation and the previously mentioned attack and decay speed of the driver.  I intentionally tried to feed the CL2 tracks that were overly busy to try and force it to image poorly or congest and as long as I stayed away from the previously mentioned issue with compression on some masterings, I couldn’t make it get claustrophobic.


Sound using Bluetooth:

As previously mentioned, I expected the CL2 to lose some resolution when using the Bluetooth cable and it does, but not as much as I thought it might.  I also found it less prone to the issue with harsh mids when using the bluetooth cable.  (I have no idea what DAC is included in the cable as I haven’t been able to find any details, but I suspect it to be something slightly clinical based on listening experience).   In the overall, I think the CL2 ranks as the single best bluetooth earphone I have had the pleasure of hearing.   Battery life was literally an entire work day.


Thoughts / Conclusion:

Honestly when I signed on to the tour, I expected the CL2 to be a technology tour-d-force and a way for RHA to show off what they had done to miniaturize a planar magnetic driver.  I expected it to be somewhat flawed in signature as almost all things are and first runs tend to be even more so.   I saw Bluetooth as a poor choice as it would either detract from the package if poorly implemented or add little to it if done right, and I figured it would be one I would happily pass along to the next reviewer while telling myself I had things in my collection that sounded at least as good and cost less.   Turns out, I can be kinda dense sometimes.   While the CL2 is a technology show for sure, its a good one.    The CL2 earns high marks in build quality, comfort, kit, Bluetooth implementation, and Soundstage.   When paired with the right sources and source material, it delivers exceptional sound quality.    Some will have no issue with spending the additional money to surround the CL2 with the other components it needs to do its best work, others not.   My own feeling is that the CL2 is a highly revealing (if at times over-zealous at it) in ear with a lot of redeeming features.   Sure, I’d be happier if they found a way to tune the mids to play nicer with less than perfect source material, but I am not unhappy with it as it is now and I’ll be more than a bit sorry to see it go.