[kostalex]

[size=medium]RE0 rivals ER-4S, beats E500 and ER-4P[/size]

RE0 is a new canalphone which tops Head-Direct.com lineup of canalphones. It is priced $169 on Jan 8, 2009 and aimed to compete with top dynamic earphones as well as with mid-level balanced armature earphones. Fang from Head-direct suggested me to review it and sent me a sample.

Here I compare RE0 to Shure E500 (same to SE500 and SE530), Etymotic ER-4P and custom tipped ER-4S. Pay attention that both of these ER-4S and E500 cost almost twice as more as RE0 does.

This review gone through the stages and revisions, so the whole story became too long. This is why I am starting with the conclusions, helping busy readers to save their time:

Sound signature: RE0 sound is a kinda cross of Ety and Shure sound sigs. It is detailed and relaxed, fast and smooth, neutral and lively at the same time. RE0 sound is a bit tubey – smoothed, slightly compressed, featuring a hint of warmth. I can not tell the exact headphone which sounds the same to RE0. The most similar is Denon D2000, if you equalize its bass with the rest of the spectrum. DT880 is also sound close when driven by tubes, though DT880 is boring in comparison. See next section “Multiple voices” for more comparisons.

Performance: With good source and right tips RE0 performs close to my custom tipped Etymotic ER-4S. Both belong to the top IEMs league, each has its own advantages which are subtle by comparison:

1. Ety has better details, speed, clarity and deeper bass.
2. RE0 has better mids, highs, smoothness and bass weight.

I prefer ER-4S over RE0 but I am not sure if I would choose it again without the custom tips.

With regards to the Shure I think its sound is well tuned specifically for portables. Weighty bass compensates typical bass deficiency of portables. High sensitivity helps to discover the details, while rolled-off highs are forgiving to MP3 artifacts and source shortcomings.

Outstanding transparency: RE0 is very transparent and utterly neutral earphone which lets you listen to the source itself. Every time I listen to Etymotic or Shure they jump at me – “Hey, it is me! Do you hear my unique sound signature well?”. Every time I listen to RE0 it disappears behind the source. With RE0 it is very easy to discern the sources/amps, it may substitute ER-4S for gears/records analysis purposes. It does not need powerfull amping, but benefits of quality one.

Genres matching: The tonal balance of RE0 is among the best I heard from the headphone, earphone or earbud – it is ruler flat! This along with it other competencies make RE0 an absolute all-rounder for any genres.

Value: Being twice less expensive than both of its contenders, RE0 also provides best bang for the buck in this comparison.

I heartily recommend RE0 if:

1. you listening to very different genres
2. you insert and pull out your earphone frequently
3. you move while listening
4. you do not like deep insertion of IEMs
5. you do not like the sound of armature drivers

Congrats to Head-Direct for excellent entering to top IEMs league!

My updated ranking of the cans I listened/reviewed

I divide some of the cans I listened into the 3 classes - Hi-Fi, Mid-Fi and Low-Fi. I divide each class further with 3 levels and marked the headphones I reviewed with bold:

H1 HD650, W5000, SR-404, ER-4S*
--- RE0 is here
H2 Denon D2000, AKG 701, W1000, E500
H3 DT880, ER-4P*
M1 DT990, AD1000, K501, Ergo 2, UM2, OK1
M2 DT770, SR225, HD595, AD900, K271, MDR-F1, E4c, PK1
M3 AD700, HD555, HD280, DT660, SR80, ER-6i
--- CM700 is here
L1 iGrado, A900, HD485, K181, E3c, UE 5 EB, OK2
L2 PortaPro, PX100, DT231, K81, D-Jays
L3 KSC-75, SportaPro, PXC 250, K27i, UE 3, E2c, CX300, modded Marshmallow
--- PK2 is here
the rest of the earbuds

*My ER-4P/S has soft silicone custom tips which sound MUCH better than any of the universal tips from Ety, Shure, Westone, Sleek-Audio (I tried all).


Look and build

I like RE0 style and choice of materials. Metal earpieces are small and elegant, they feel sturdy, cable does not tangle, plug is slim enough to fit old iPhone recessed jack. I recommend you to take a look at some other shots of RE0 in these reviews:

[REVIEW] Head-Direct RE0 - a new contender for the best IEM by ClieOS
REVIEW: Head-Direct RE0 by MD1032
Review: Head-Direct RE0 by antonyfirst
Mini comparison - V-mode Vibe (1st gen), Denon C700, Yuin PK2, Head Direct RE0 by mvw2

I believe these reviews are also interesting to read. I’ve yet to read them myself. I did not read them before to keep my mind open to RE0.

My ranking system

I use the following notation:

1. A = B, when neither earphone is better
2. A >= B, when advantage of A is subtle or hard to detect
3. A > B, when advantage of A is obvious, but is not valuable to me
4. A >> B, when advantage of A is valuable for me and is a good reason for upgrade

[size=medium]ROUND 1: Maximizing the Sound Quality – lossless, amping and mods[/size]

I used the Pico as DAC/Amp and lossless files played by Foobar. I also converted ER-4P to ER-4S by adding PtoS cable. I choose the best sounding tips for each IEM:

1. E500 - shallow custom silicon tips. They are hard enough to make the bass tighter than any of the Shure universal tips, either foam and silicon. Being shallow, they do not increase the bass weight and this is good with E500.
2. ER-4S – deep custom silicon tips. Once I went through numerous rebuilds choosing the best size, fit and material. Finally I settled with these nice tips which add desired bass, warmth and some smoothness to Etymotic sound.
3. RE0 – UltimateEars tips. They are stiffer than RE0 black stock tips and provide tighter sound. They sound the same to famous Head-direct bi-flanges while are easier to insert. Bi-flanges isolate better though. EDIT: UE tips do NOT sound the same to stock bi-flanges. See Update 01/31/09 for more info.

Above are some harder custom tips I tried with E500 later. They are slightly less comfortable than short silicon tips. But they sound better and let E500 get closer to RE0.

[size=small]Sound quality rankings:[/size]

Soundstage width: E500 >= RE0 > ER-4S
Soundstage depth and height: E500 >= ER-4S >= RE0
Positioning: E500 > ER-4S >= RE0
E500 is the very best, but either earphone performs well.

Bass depth: ER-4S > E500 >= RE0
Bass attack and details: ER-4S > RE0 > E500
Bass weight: E500 >> RE0 > ER-4S
ER-4S has the top quality but lacks quantity. RE0 is balanced while lacks depth by comparison. E500 is slightly boomy and also slower. I prefer ER-4S, though neither is satisfactory to me when comparing to the cans like W5000.

Mids details: ER-4S > RE0 > E500
Voices timbre naturalness: RE0 >= ER-4S > E500
Electric guitars aggression: ER-4S >= RE0 >= E500
Whoa! RE0 is a winner followed closely by ER-4S, which is kinda dryish and a bit too aggressive on guitars. E500 comes 3rd with its excessive warmth.

Highs details: ER-4S >= RE0 > E500
Highs extension: RE0 >= ER-4S >> E500
Highs strength: RE0 >= ER-4S > E500
RE0 has the best highs I ever heard from portable headphone. They are well presented and of extremely high quality. In no way they are exaggerated. ER-4S also performs excellent here, while E500 is dark and recessed to me.

Speed: ER-4S >= E500 >= RE0
Smoothness: RE0 >= ER-4S >= E500
Clarity (instruments separation): ER-4S > RE0 = E500. I was surprised that dynamic earphone may compete with armature IEM in terms of speed and instrument separation.
Sibilance: neither is sibilant to talk about.

Tonal balance: RE0 >> ER-4S = E500
Genres versatility: RE0 > ER-4S >= E500
Both ER-4S and E500 are unbalanced in each own manner, while RE0 offers perfect balance.

[size=small]SQ ranking according to the personal prefs: ER-4S >= RE0 >= E500[/size]
The winner is ER-4S with custom tips (which cost me arm and leg).
RE0 takes the 2nd place yielding to ER-4S basically in bass depth.
E500 comes close 3rd slightly flawed by excessive bass and warmth.

Non-SQ factors:
Sensitivity: E500 >> RE0 > ER-4S. Extra sensitivity lets E500 down with some sources, pulling the hiss out.
Wearing comfort when you do not move: E500 > ER-4S >= RE0. Custom molds rule! Stiff UE tips sound nice with RE0, but they are a bit fatiguing.


[size=medium]ROUND 2: Portable use – maximizing the convenience[/size]

This time I compared following some restrictions / requirements which are typical for portable use:

1. Unamped source - I used iPod Classic 160 GB
2. Lossy files - 192 Kbit typical bitrate
3. Appropriate tips – comfortable to wear, easy to insert and pull out

All these factors affected the sound, of course. Here are the tips I choose:

1. E500 - stock Shure grey silicone olives.
2. ER-4P - Etymotic soft blue bi-flanges (I cut off the 3rd flange). I believe that modern version is frost ER4-15SM.
3. RE0 - stock mid-size black tips. EDIT: Later I found that these tips degrade the RE0 SQ much more than absence of the amp. So take this into consideration when reading the following rankings. I’ve decided not to revise the comparison due to my laziness. On other hand, it shows you one of the most relaxed sound signatures of those RE0 is capable for. So it may be useful as is . EDIT2: I also found that these are not stock tips! Sorry, I mixed them up by mistake. Anyway, they are quite close to stock mid-sized tips. For those interested in details, check #6 and #7 in Update 01/31/09.

I choose ER-4P over ER-4S since the latter is not well driven by portables.

Sound quality rankings:

Soundstage width: E500 > ER-4P > RE0
Soundstage depth: E500 > ER-4P >> RE0
Positioning: E500 = ER-4P > RE0
Unfortunately, RE0 has a real loss here, while E500 reigns with its almost-full-sized-cans soundstage.

Bass depth: ER-4P > E500 > RE0
Bass quality (attack and details): ER-4P > RE0 >= E500
Bass weight: E500 > RE0 > ER-4P
E500 performs nice here with ease. RE0 is missing a depth, but holds the competence in the rest of the bass features. ER-4P is slightly anemic and this compromises its superb bass quality.

Mids details: ER-4P > E500 > RE0
Voices timbre naturalness: ER-4P > E500 >= RE0
Electric guitars aggression: ER-4P > RE0 > E500
ER-4P is a clear winner. The choice of RE0 or E500 depends on genres preferences.

Highs details: RE0 >> ER-4P > E500
Highs extension: RE0 > ER-4P > E500
Highs strength: RE0 >= ER-4P > E500
RE0 is still unbeatable in highs.

Speed: ER-4P > RE0 >= E500
Smoothness: E500 >= RE0 >= ER-4P
Clarity (instruments separation): ER-4P > RE0 = E500
Sibilance (worse first!): ER-4P > E500 = RE0. It seems to me that sibilance is originated from source/record rather than from earphone itself. Nevertheless, some indulgence to portable sources/formats is appreciated.

Tonal balance: RE0 >> E500 = ER-4P
Genres versatility: RE0 > ER-4P > E500

SQ ranking according to the personal prefs: E500 >= ER-4P > RE0
RE0 lacks bass depth and soundstage size with Classic. Both E500 and ER-4P provide deeper bass and better ambience. But all these things come at the expense of neutrality – both E500 and ER-4P color the sound in each own way. In contrary, RE0 has the most balanced sound of three. It adds less character to the music and serves more genres well.

Non-SQ factors:
Sensitivity: E500 >> ER-4P > RE0
Wearing comfort on the road: RE0 > ER-4P > E500. RE0 provides the best comfort, beating even the custom tips. It does not intrude deep and the tips are very soft. Over-the-ears cable of E500 does not keep its position well when I move.
Easiness to insert and pull out: RE0 > ER-4P > E500
Isolation: ER-4P > E500 > RE0. Note, that you may get better isolation with RE0 stock bi-flanges.
Microphonics (worse first!): ER-4P > RE0 > E500. Over-the-ears cable of E500 reduces microphonic almost to none. RE0 smooth cable provides bearable microphonic, while twisted ER-4P cable is really annoying.

Which one is better background player?
RE0 > E500 >> ER-4P
This is very important category for me. When I listen portable I am usually use the music as a background. My primary tasks may be reading, writing, thinking, etc. I found that ER-4P does not let me to focus on primary task, involving me to the music hardly. Both E500 and RE0 provide me with a choice whether to listen carefully or focus on something more important. More on background listening in my Earbuds buyer guide.

[size=small]General (sound + other factors) ranking: RE0 >= ER-4P > E500[/size]
This choice is strictly personal since it depends on your style of portable listening. Some listen in subway, some while walks (though it is not safe), some on the beach. Some listen to the music carefully, some use it as a background. Our mileages may vary. RE0 is third on SQ but it is so convenient – very comfortable, easy to insert and pull out, acceptably microphonic. It is also the best background player, so it wins for me. ER-4P provides the best balance of pure SQ and convenience. But it does not allow to listen music on background, so it comes second. E500 is true SQ leader with Classic but it is bulky and too cumbersome from tips to plug.


[size=medium]Sensitivity, amping and synergy [/size]

I was not really sure why Classic > RE0 combo does not sound as good as Classic > E500. It seemed to me that RE0 just faithfully shows me the restrictions of the iPod itself. I decided to check RE0 with different sources to prove or refute this. So I listened to RE0

1. unamped with iPod Classic, iPod Mini, Sansa Clip, iPhone 1st gen, Shuffle 2nd gen
2. amped by Pico, TTVJ Millet, XIN Supermicro, WooAudio 3, FIIO E3

And I may definitely say – in no way RE0 is inefficient earphone which requires powerful amping to shine. Instead, it is very transparent and utterly neutral earphone which lets you listen to the source itself. Every time I listen to Etymotic or Shure they jump at me – “Hey, it is me! Do you hear my unique sound signature well?”. Every time I listen to RE0 it disappears behind the source. With RE0 it is very easy to discern the sources. Due to its transparency it may substitute ER-4S for gears/records analysis purposes.

Its fidelity lets it down with some sources though. It does not emphasize delightful details like Etymotic. It does not add warmth and weighty bass like Shure. So you can not cure or mask some source deficiencies with RE0. You can not use it to beautify source or record as well.

With regards to sensitivity: even the Shuffle may drive it loud enough. It is more sensitive than PK1, for example.

So RE0 is quite unpretentious in terms of synergy. The typical equation of synergy does not work here well: “My headphone is A sounding, so if I want to get C sound, then my source has to be (C-A) sounding to complete my headphone.” If you like C sound signature, just get the source with C sound and you are done. Anyway, RE0 has some character of its own, though it is very delicate. And you may squeeze the last tiny bits of SQ with the matched source which is:

1. Fast
2. Dynamic
3. Detailed
4. Extended well deep to the lowest lows

I bet Meier Move would match RE0 perfectly. My Move is out of home so this is an assumption based on audio memory. I’ll check it when my Move returns to me.


[size=medium]Update 01/31/09 - Multiple voices of RE0 with different tips[/size]

Every IEMs sound I heard depends on tip used. RE0 turns to be among the most dependent and I really appreciate this. It is more dependable on tips than Etymotic by comparison. I tried every different configuration of SleekAudio SA6 and I may say that RE0 is even more variable.

Changing the tips, I was able to move it from relaxed background player to the true rocker earphone full of energy and fun. And I was able also to select interim sound signatures between those extremes.

Sound varies on listener ears as well as on the tips. Thus I can not recommend you the best tip overall or proper tip for some genres. Instead I recommend you to try as many tips as possible. This lets you to have 2 or 3 of different sound signatures with single RE0.

As for me, I was lucky to discover 3 sound modes of RE0:

1. Hi-Fi – see tips #1 or #4 below
2. Rock – see tips #2 or #3 below
3. Background – see #8 below

Let me to share some of my experience with the tips. There are the tips properties which affect the sound in order of importance:

• Depth - it determines how much of air volume will be pumped by driver. Deeper tips produce faster sound with better dynamics.
• Inner tube diameter - narrow tubes soften the highs, hide the details and vice versa.
• Stiffness - softer tips soften the bass attack and reduce bass weight and depth.

Here are the tips I tried, #1 - #4 at the top and #5 - #8 at the bottom:

• Hard shallow pink custom tips, narrow inner tube: The most mature Hi-Fi sound resembles D2000 very much. Bass is deep, articulated and well integrated to the rest of the spectrum, Highs softer by a hair than those of D2000. You may add some highs with ClieOS nozzle mod (follow his review link at the beginning of OP. Comfort is good.
• Stock transparent bi-flanges, stiff: V-shaped response, bass is deep and tight, electric guitars roar very nice, overall sound is forward and aggressive. Sound signature reminds me Grado, bass-boosted Ety, DT990 tamed on bass and highs. There are plenty of fun and energy for rock music. Comfort is bearable.
• Stock white bi-flanges, soft: Close to #2 with slightly lesser and softer bass. Comfort is very good.
• UE tips, stiff: Very balanced sound, seconds to #1 only, adds highs a little and lacks some bass weight and depth in comparison. Sound signature reminds me tubes-driven DT880. Comfort is average.
• Shure E2c black olives, narrow inner tube, stiff: Same to #4 with deeper bass and softer highs. Comfort is average.
• Stock mid-sized tips: Softened version of #4 sound. Comfort is very good.
• Unknown black tips: These are tips I used for Round 2 by mistake. Sound is between #6 and #8, featuring significant loss of bass depth, soundstage, details and dynamics comparing to #4. Comfort is good.
• Sennheiser CX300 tips: Most pliable and comfortable tips. Sound is the most relaxed, softened, compressed, dark and veiled. So this is a best solution for background listening. Sound signature steps to HD600 / HD650 direction. Comfort is excellent.

I do not list other tips I tried since they do not fit. It was easy to detect this by huge bass loss. If you hear the same, do not judge the earphones severely but try other tips instead.


[size=medium]UPDATE #2 - ROUND 3: Revenge of RE0, ER-4P dethroned![/size]

After the experiments with various tips I was intrigued – how would properly tipped RE0 stand against Etymotic? I also thought that there are many head-fiers with portable amps and very few with the custom tips. So the second question is – how does RE0 stands to Etymotic when both are amped and equipped with universal tips?

I was not willing to make over the whole comparison step by step. Instead I decided just to listen to some of my favorite songs. I attached transparent bi-flanges to RE0 since they sound closer to Etymotic. I attached tri-flanges on ER-4P, compared both RE0 and ER-4P unamped from Classic…

RE0 + bi-flanges beat ER-4P + tri-flanges, when driven by Classic!

Well, tri-flanges are not the best sounding universal tips for Ety. So I changed them to the black foam for ER-6 (ER6-14F). I do not like ER-4P black foam (ER4-14F) because its wide inner tube makes the highs too spiky for me. ER6-14F inner tube is narrower thus highs are softer. BTW, I’ve read somewhere at head-fi that Etymotic changed the inner tube of ER4-14F recently to the narrower one, nice move.

ER-4P + foams beat RE0 + bi-flanges, when driven by Classic.

I think that latter is not fair comparison indeed. Foams are not portable solution. You have to squeeze the foam by the fingers which are not clean when you are outside. Foams are also scratchy and do not last long.

Then I went amped. Source was Classic with LOD, amps were Meier Move and Xin Supermicro IV w 4/11 mods. RE0 kept bi-flanges and I tried ER-4P with both foam and custom tips.

RE0 + bi-flanges beat ER-4P + either tips, when amped!

Amped RE0 does not yield ER-4P in terms of speed and details, while supersedes it in terms of clarity and tonal realism.

Wow! ER-4P is dethroned by dynamic canalphone made in China. Lets the flame begin…

Do not hurry guys. There is still ER-4S left and I am its long time fanboy. I spent a lot of money and so much time modding my Ety to death. I went through numerous rebuilds of silicone custom tips. I carefully chose the most synergetic portable amp for them (Supermicro it is). I even recabled them with OFC (though I made all the comparisons with stock Ety cable). So it is not easy for me to sustain a defeat. See my ultra modded ER-4S below:

There is no obvious winner between ER-4S and RE0 for me right now. Amped RE0 with bi-flanges gets dangerously close to ER-4S, featuring very fast transients, good details, better bass proportions, more realistic mids. I feel that ER-4S is better by a hair … or by a split of a hair. But it is not easy to detect and even harder to describe yet.

The final round (ER-4S vs RE0) will definitely take some of my time. I do like to have as few cans as possible. So I am really interested to determine the winner and let the loser go. Since I already maximized the SQ of my ER-4S, I should give my best efforts to RE0 also.

Stay tuned.

[size=large]UPDATE #3 - FINAL ROUND: Modding RE0[/size]

I made ClieOS mod to RE0:
Quote:

Originally Posted by ClieOS /img/forum/go_quote.gif Here is a mod you can try on your RE0 - it is the same mod as the RE1 mod I described before. Basically, you remove the foam inside the nozzle (behind the mesh-like filter) to improve the SQ.

RE0 improves with this mod, getting closer to ER-4S in terms of sound signature. There are few differencies left after the mod, thus I was able to focus on them and make the final choice. So:

1. ER-4S is faster, has better clarity
2. RE0 is more neutral, has better vocals

I decided to keep ER-4S because:

1. I like to have at least one ultra-fast headphone. Would I keep Ety if I had STAX? I really doubt.
2. I use my IEM primarily at home, sometime with tube amp. Would I let RE0 go away if I need IEM for portable use? Exactly not.
3. I invested a lot of time and money modding my Ety for fuller bass (custom molds) and softer sound (recabling). Would I prefer Ety if it were stock? I'm not sure.

So, even if you are a hardcore Ety fanboy like me then you will likely find RE0 to be almost as good as ER-4S. Moreover, it may suit you even better in some cases, like portable use.

If you are looking for top-notch SQ with excellent neutrality and hate some of Ety shortcomings then RE0 is next choice I recommend. My daughter likes it very much. She can not stand ultra-sharp sound of Ety with electric guitars as well as lean bass. So smoother sound and fuller bass of RE0 fits her bill precisely.

 

[FrederikS|TPU]

Nice review!

Although I think you miss "bang for the buck" in your recommendation. I think they represent the best value high end earphone. I mean at $169 including a FiiO E3 amp they cost way less than the SE530s or the ER4Ps with custom made tips.

 

[Calexico]

If they only had an over the ear design I would probably pick them up as my first "high end" IEMs. But that's a long ways away.

I'm confused though. Why are the ER4Ps rated so highly in everything? Do the custom moulds really do that much?

 

[kostalex]

Quote:

Originally Posted by Calexico /img/forum/go_quote.gif If they only had an over the ear design I would probably pick them up as my first "high end" IEMs. But that's a long ways away.

I just tried RE0 over-the-ear and they fit well. Phonac sells (or will sell) silicon over-the-ear cable guides. This may help to secure this position.

Quote:

Originally Posted by Calexico /img/forum/go_quote.gif I'm confused though. Why are the ER4Ps rated so highly in everything? Do the custom moulds really do that much?

Yes. They cure the bass deficiency.

 

[kostalex]

Quote:

Originally Posted by FrederikS|TPU /img/forum/go_quote.gif Although I think you miss "bang for the buck" in your recommendation. I think they represent the best value high end earphone. I mean at $169 including a FiiO E3 amp they cost way less than the SE530s or the ER4Ps with custom made tips.

You are right. Both contenders cost 1,5-2 times more than RE0.

 

[LeonWho]

Very nice review. Head-Direct makes quality products.

 

[robm321]

Very solid comparisons - thanks!

 

[Tomikans]

ahh so many options to choose from..though it'll be hard for me to choose the re0 since i already own the re2's (even though re0's are in another league). I would like to try out the other two headphones.

 

[kostalex]

Added "best bang for the buck" to the OP.

 

[ClieOS]

Very nice and detail review. RE0 has became my current most-used IEM in all my IEM since I received it

 

[forsberg]

Excellent review! I wish more head-fi comparison reviewers can post pics along with the review as you did!

 

[younglee200]

Only problem I had with the RE0 was that there was no available comply / custom tips (not that I would buy them considering how much it costs) available for it, and the head-direct white bi-flange tips & or any other stock tips hurt my ears after about an hour.

But sound wise, I do have to agree with OP that RE0s are a great value. If you have no problem with its fit I'd definitely recommend it as well.

 

[kostalex]

Try CX300 tips (sennheiserusa.com), they are the softest and most comfortable universal tips I knew.

 

[FrederikS|TPU]

Quote:

Originally Posted by younglee200 /img/forum/go_quote.gif Only problem I had with the RE0 was that there was no available comply / custom tips (not that I would buy them considering how much it costs) available for it, and the head-direct white bi-flange tips & or any other stock tips hurt my ears after about an hour. But sound wise, I do have to agree with OP that RE0s are a great value. If you have no problem with its fit I'd definitely recommend it as well.

The Comply T400s would fit, the diameter and tip retention system has the same dimensions as that of Ultimate Ears products.

 

[Ballz2TheWallz]

Quote:

Originally Posted by LeonWho /img/forum/go_quote.gif Very nice review. Head-Direct makes quality products.

Its kinda sketchy if you ask me I think they must have stolen plans used to build a more expensive IEM and manufacture them for a cheaper cost or something

I find it amazing that some random chinese company can produce products out of nowhere that go toe to toe with headphones from a wide range of companies that often cost significantly more. Furthermore they're using dynamic drivers that are designed to be more focused and accurate at higher frequencies instead of using them for boomy bass as opposed to using balanced armatures which so many other companies use like etymotic.

As for the review, shouldn't bi flanges give a better seal and better bass with the RE0's? I would think if you used bi-flanges or something on a more even ground with the custom molds that they would perform better.