Planar Magnetic IEMS - An emerging segment?

I see, I am in the process of trying different combinations out now. I do hear some differences subjectively but I wonder if that would be the same if I were to do a blind test. I have yet to find any cable combination that has a very drastic difference in sound presentation. What I did find so far, in terms of measurements, is that seems that due to the lower resistance of silver cables in particular (or even the particularly shorter cables), the signal amplitude and thus loudness seems to be increased (albeit only slightly at about 2 to 5 db based on my measurements).

@pennstac I do own a set of Stax SR-001 MKIIs (fat cat modded). I found there was a significant difference in terms of bass after the mod than before. In my opinion, it seemed that the electronics on the amplifier was the limiting factor rather than it being an “electrostatic IEM”, that was preventing it from producing more bass. Even when I just switched the battery supply from the AA 1.5v series Alkaline batteries to parallel 3.7v Lithium Ion Cells (before starting the Fat Cat mod), there was already a noticeable increase in bass. I guess there were some limitations back then when Stax was first designing the SR-001s and these were addressed with the many mods that we see around.

Anyways, wishing you guys a happy 2019 and another great year of listening! :grin:


Happy New Year @DanicoLabs. You definately wont find a cable that makes a drastic difference anywhere IMHO. Cables will only bring very small differences. And it is a point of debate that they change sound at all. I am a believer but it won’t change much. Many will say it’s placeno and it may well be. But to my ears I hear subtle differences. Though I won’t pay huge amounts for cables.

You may find that in the end you don’t hear any change in sound for you personally. And that’s fine. At least you’ve remained open minded enough to try it. Also your point about resistance change may indeed be the cause of subtle sound differences. For me personally using a balanced cable made more of a difference than materials it was constructed from. As always it just my personal opinion. :grin:.


I agree wholeheartedly. IMO, cables make a difference up to the point of electrical functionality with a safety margin, but then (at best) they may slightly change the color one way or another. I strongly advocate buying low priced balanced cables, and spending more money on better headphones, balanced amps, and balanced DACs. In that order.

Recently I’ve been testing the resistance (ohms) on a whole lot of cables with my multimeter. With probe-to-probe contact it reads 0.2 or 0.3 ohms. With any cable I’ve tried it reads 0.4 to 0.9 ohms.

Regarding balanced cables, their potential impact can be demonstrated very simply with a multimeter. For example, I tested a TRS connector on one set of headphones – ground to left ~75 ohms, ground to right ~75 ohms. Left to right ~150 ohms. So, the common ground doubles the resistance and clearly can carry a signal to the other channel. With a balanced TRRS cable there’s no way to directly connect the left to right grounds, and no way to cause substantial interference with the other channel [barring shielding issues and cable damage.]


I’ll be getting a loaner of the RHA CL2 soon from RHA. Excited to hear what the polarizing fuss is all about. The measurements show some crazy upper-mid spike that seems to be very polarizing. I tried to EQ my UM ME1 to have the same measurement response and it was weird, but I’m excited to hear it for real now.


Wow nice! Will you be posting any review of it? :grin:

I’ll probably post some impressions for sure

I this the RHA iem with Ceramic driver? I should probably look this up myself. :grin:. Anyway it’ll be good to hear your impressions.

RHA CL1 is ceramic driver. CL2 is planar magnetic

Unique Melody ME1 (left) and RHA CL2 (right) Planar Magnetic IEM buddies

I was out last night so didn’t get a lot of listening time. My quick initial impressions are: very comfortable. great build quality. very detailed and fast. lean bass. a little too bright and slightly off timbre. good soundstage and imaging.


Here’s some I took today using EARS and Dayton IMM-6 + 2mm wall thickness rubber tubing:

RHA CL2 vs Unique Melody ME1 (CIEM) – EARS Diffuse Field Compensated (based on Etymotics ER4)

This a comparison of the raw measurements from my two measurement setups for each IEM

This is a Waterfall CSD chart using the Dayton IMM-6 setup. Basically looks like the RHA CL2 is faster in the mids and treble, while ME1 has similar bass response. I think the bass region on the charts is probably not very accurate. I think the CL2 attack is probably faster than the ME1.


These are interesting measurements. Actually shape of the curve of the UM ME1 seems to remind me somewhat of the i-Sine 20. There is an initial peak at around 3-4 Khz and thereafter it remains flat in the mids and tapers downward after 10K.

Whereas the shape of the RHA CL2 follows a V-shaped profile with a similar peak at around 4 Khz and then another peak at around 12-15 Khz. I wonder if the closed design of the RHA reflects the higher frequencies more efficiently as opposed to open designs like the UM ME1 and the i-Sine 20.

To your ears, would you say the highs of the RHA CL2 are sharper than the UM ME1? Did the V-shaped profile affect your perception of soundstage

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Here is a post I made on another forum where the CL2 sound is more controversial :slight_smile:

My weekend impressions with it so far seem to think that male vocals sound fine and female vocals are slightly veiled. The boost in that upper mid/lower treble region makes guitars and strings really emphasized so that you can hear every little pluck and cymbals extra splashy, but I find to sound a bit unnatural, especially when you listen to other headphones and IEMs and listen to speakers or a live show – I was at a concert this weekend for example. I actually do prefer headphones with a slight boost in this region – a couple of my favorite headphones/IEMs have a slight boost here, but this CL2 boosts an additional 5+ dB more, which I find a little more than necessary.

Sounds a little “tinny” in “Dreams”.

Switching tips does help tone some of it down, but still find it unnatural. The speed and attack is awesome but also, I think, makes it sound a little unnatural too.

EQ does help soften it though, and makes this sound a lot better.

Now to answer your questions:

The profile may look V-shaped, but the bass does not sound large. It actually sounds a lean and I think that has a lot to do with the fast attack and decay it has, so that the bass never hangs around long enough to sound like a mid-bass hump. In reality, I feel the ME1 has more weight to it, and sounds much more rich and filling.

The highs on the CL2 are significantly more sharper than really anything I’ve heard in a higher priced headphone. It reminds me of a cheap tinny V-shaped headphone in that sense, but it’s speed and clarity are really good. I feel like the clarity is really due to the lift in the treble, and not that it’s actually more clear than the ME1. The ME1 has a lot of detail in it but the sound profile is much more balanced, and leans a little dark with it’s treble roll-off.

The large peak in around 4KHz and at 12KHz makes some strings and cymbals very troubling and higher pitched female vocals sound just slightly off.

Again, EQ with a significant drop in those two regions makes these sound more accurate and softens a lot of the timbre issues. I think it behaves well to EQ luckily.

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@DanicoLabs Any updates on your new IEMs?

Hey! Thanks for asking. Yes, actually a lot has changed, we have done major developments to our IEMS since the last time we’ve spoken here. Just some updates:

  1. The space within in the casing has been optimized and we are able to increase the size of the drivers further. They now measure 16.75 mm x 12.25 mm, and I believe they are the largest ever planar drivers in a closed IEM. The larger driver greatly increases the soundstage and bass.

  2. To increase the warmth of the sound as well as the low end, we are planning to switch our casing from polycarbonate to wood. We have spent a great deal of time traveling around to find different woods and we have been assembling prototypes to test the outcome. It was technically challenging to create these as they had to be made from different parts (partly CNC and partly by hand). Here is a teaser since you asked :wink:

  3. We have also been working on a Type-C balanced amplifier for use with our IEMS which dramatically enhances the sound experience. We thought that we had to make our own balanced adapter-amplifier combo because the majority of the adapters we tried were actually single ended once we took them apart and studied their wiring. Here’s how it looks like:

How has your listening experiences been? Recently heard or tried any new planar magnetic equipment? I’ve been to Japan recently and I was impressed with the choices in planar headphones they had on display. :grin:


Nice update! That does sound like a larger driver than others. I just tried the Tin P1 and wrote a review of it on here and my blog this weekend. It’s also a closed back planar with 10mm driver.

Wood - I’m interested in how that goes. What types of wood are you using? The darkest ones in the middle look nice!


Wow, I have only just heard of the Tin P1, it looks to be great value for the money. I have seen the review on your site. I like how you show the measurements and correlate with your impressions. Sometimes it is quite hard for me to picture the sound from may other reviews which are mainly descriptive in nature. The sibliance seems to be quite an issue and I have seen in some reviews describe the Tin P1 as too ‘revealing’ (I wonder if they are speaking of the same issue?). In my experience with planar magnetic drivers, this could be due to a stiff membrane that is driven by high power. Out of curiosity, did you “burn in” the Tin P1 before the review? (Though I know not everyone believes in burn in)

We are trying a wide range of woods to see which sounds best. So far we have narrowed it down to a few choices, rosewood, cherrywood, etc. Personally, I like the dark ones as well :grin: it is actually Ebony. I think wood IEMS are uncommon (JVC is the biggest proponent right now), so we are taking a shot at making our planars using wood as no one has tried such a pairing thus far. I’m liking the results =]


Thanks for the feedback! I am actually quite impressed with the P1. It does have issues in some songs, but it generally sounds pretty pleasant and does push the boundary a bit on the treble. Another problem is the soundstage isn’t as wide as I originally thought so in some songs with really busy instrumentation, it can sound a bit overwhelming with all the instruments coming at you at once in full clarity since the treble is boosted up quite a bit.

I didn’t burn-in given the time requirements for the review, but I did play it over about 40 hours now and haven’t really seen any noticeable sound change.

Wood is exciting! Meze makes a couple budget wood IEMs Meze11 and Meze12 as well as ThinkSound, but yea the market for it is pretty small. I recently got the ZMF Verite, and I was talking to some folks the other day that I want an equally stunning wood iem to go with it. :slight_smile:


Seeing all the new excitement on the Tin P1 I’m so tempted to get my hands on one as I’m a planar magnetic lover myself :grin: In my experience making these small planar drivers, the issue is that as we shrink the driver smaller and smaller, the effect of the vibrating metal on the membrane becomes very significant.

This is a conventional planar membrane:

Whereas this is a close up of a miniaturized planar membrane:

The metal lines are packed so closely together and in some cases can be more than 75% of the area. Thus when the signal goes through, the effect of these vibrating metal lines can produce additional acoustic artifacts (such as frequency peaks). These metal lines are traditionally made using copper. There are of course ways to reduce this effect, for instance, to use a metal softer than copper. I wonder if the treble peaks seen in the P1 and even frequency peaks the RHA CL2 are as a result of this effect?

Ah its a little disappointing to hear about the soundstage… I guess I have to hear for myself to know. How do you compare it to the RHA’s soundstage?

I am a wood lover myself, but I love the combination of wood and metal. I just took at look at the Verite and the combination with how they implemented the grill looks really great! I hope that there are more wood lovers out there. Can’t wait to show you guys our final design once its done.


It’s been a while since I listened to RHA CL2, but I believe it had an average soundstage.

I think you found a nice forum for wood headphone lovers. The ZMF products have been getting a lot of love lately, for their beauty and craftsmanship as well as their sonic qualities. Your IEM shells look pretty great too, so if you can make a similar marriage of sound and natural wood beauty, you could be on to something.

Thanks for the in-depth look at some of the driver technology. It’s very interesting to read about.


Hey there! So, the earphones that @antdroid has lent to me has arrived. BGVP DM6 and TIN Audio P1. I’ll be putting the BGVP impressions up in a bit in a different thread (DM6 has all BA, so it’ll go in a different thread)

So, what do I think about the TIN P1 so far? I’m not sure if I like it. It’s got a lot going for it, but it’s got some flaws. We’ll get into that.

First off, what I like about them. It’s the first pair of planar IEMs I have ever tried. Cable has almost no noise whatsoever. There is a chin cinch (I prefer calling them chin sliders, so I’ll refer to them as this), and it can easily be slid up, to reduce any cable noise that may be there. The sound is decent, but it’s not as good as I hoped. The bass has a bit of rolloff, which takes out a lot of the rumble I enjoy with my music. The mid bass appears to be well controlled, and is more of a ‘kick’ rather than a thump. Mids aren’t as recessed as I expected, and I quite appreciate that. These are also very detailed, I was listening to Venetian Snares - My So-Called Life, and I heard a theremin at 2:20 to 2:45! I’ve never heard a theremin in this song before. Quite surprised me. Even my MH755 can’t pick up on small stuff like that. Imaging is also good.

What I don’t like, however, oof. One is comfort. I cannot wear these with certain ear tips or it presses against the outer ear canal in a way that causes discomfort. Fortunately, it doesn’t change the sound signature either way. Now, about the sound. The sub bass rolloff can be a bit of a dealbreaker for some, but can easily be fixed with an EQ. These appear to respond alright to EQ. The upper mids, and lower treble begin to show some trouble. It lacks a lot of energy from 2K to 6K, which is just around the area I’m used to having boosted (MH755, Final E2000 do this). From there, the soundstage is very closed in and congested. It hurts the instrument placement quite a bit. Then, there’s a lot of weirdness from 6.5K to 8.5K, sounds like it dips to 10K, and massive treble extension. The former bit, from 6.5K to 8.5K, introduces sibilance and a considerable amount of pierce. Treble’s a little hot on these pair, despite sounding laid back. It’s a very weird sound signature.

In conclusion, I’ll update with more later on. I might end up liking this sound signature but it’s lacking a lot of what I deem vital for my own listening preferences. Still, planar technology appears to be coming along. I’m excited to see what is in store next!