Detail Experts: Etymotics ER4, Phonak PFE122, and Hifiman RE-0

The ER4 has a very specific sound that is very polarizing. Comments on ER4’s sound range from bright, sibilant, thin, lifeless, baseless to clear, accurate, and detailed. However, after having the ER4 for a long time, I will describe the ER4’s sound as articulate, pristine, quick, and precise, though definitely a little on the thin side in the sub-bass area. There are so many things that the ER4 does really well, and it all adds up to a sense that you are listening to the music using a precision instrument. You get a feeling that you are hearing all the clarity and details that you have never heard in your music before, as if the music is injected straight into your brain without the obstruction of air. Each sound and instrument is very distinct and separate from each other, and you can listen to and focus to each instrument and sound in the music easily. There is off course a bad side to this, as I will mention later.


There are several factors that contribute to the ER4’s unique sound character. One of it is that the ER4 has very quiet background behind the sound. The black canvas is painted with vivid sound images with great transient attack and sharpness. The sounds attack and disappear swiftly, never dragging in the background for too long. Smearing from note to note and from sound to sound is minimal, and different sound images are rarely mushed together, giving the ER4 a good instrument separation and a sense of quickness to its sound. However, though the ER4 has good instrument separation, its soundstage is definitely on the small side even for IEMs. The soundscape plays in a sphere in the middle of your head, and the instruments are close to each other.

ER4’s mids and treble are both outstanding. Treble, especially with the ER4S is very clear, detailed and well extended, definitely one of the best in its price range. The mid is also clear and slightly on the warm side, with a bit more emphasis on the upper mid. You can hear the sound of the guitar plucked, lips smacking, and the fine details in the recording. The bass though, is a love or hate. On one hand, it has a surprising textural detail, able to reveal some texture behind drum hits, while on the other hand, it is almost too tight and lacks ample impact. The bass also rolls off a bit early, making is less suitable for some music, notably pop, dance, or RnB. The good side is that the bass presentation doesn’t stand in the way of other parts of the frequency range.

For all the good qualities, and clear, detailed presentation that the ER4 has, it is definitely not neutral. The sound is simply a bit thin sometimes, especially in the ER4S setting, and less full-bodied than real life sound. The emphasis on treble and upper mids, with relatively less mid warmth means that the ER4 is giving a raspy quality to voices more than what exists in the recording. The ultra fast attack and short decay is almost too fast.

Talking about detail, the ER4 also tends to focus in a specific area of the frequency response. It is detailed in a sense that it really pushes out the details that reside in the upper mid and treble area to the front, while other areas of the frequency response are a bit in the background. The thud of drums and airy instruments including strings, cymbals are pushed to the front in a crystalline but a bit lean presentation. Some instruments like bass, cello, and percussive have just enough body but the decay is very short. A lot of people try to make the ER4 sounds more liquid with amplifiers, source, and cables pairing, which fortunately, works well as the ER4 is quite revealing of the setup behind it. I also recommend some Shure Black Foam Sleeves (a.k.a. Shure Olive Tips) for a slightly warmer presentation.

So what’s the difference between the ER4P and the ER4S? I am using the ER4P+impedance adapter as an approximation of the ER4S sound. First, the ER4S is harder to drive, and out of some portable players can sound a bit strained, while the ER4P sounds quite okay out of my Ipod Nano. However, both of them including the ER4P won’t really shine until I paired them with a better setup than direct to the Ipod Nano. The ER4S has a more emphasized and apparent treble than the ER4P, which is good since they have some good treble. It also improves upon the strong points of the ER4P (imaging, separation, speed, transparency, clarity, bass tightness). At the same time, quite a bit of warmth is lost in the mid and bass area when compared to the ER4P. I think this is an important point to consider, since the ER4S can sound quite clinical-sounding for a lot of people. The Nuforce uDAC is relatively warm sounding, and I was surprised at how clinical the ER4S sounded through it. The ER4S has more technical prowess than the ER4P, but it needs a good setup to really shine and further separate itself from the ER4P. I have heard an ER4S out of a proper desktop setup costing several times the price of an ER4S, and the harshness is almost gone, with all the goodness intact. Out of the uDAC, I prefer the ER4P for longer-term listening, though the ER4S sounds better in short doses.

In summary, when imagining the sound of the ER4, think about heightened or maybe even hyped sense of clarity, detail, separation. This kind of sound can be a bit tiring, but it is a very unique presentation, that is peerless among other IEMs and headphones I have tried. While the sound may not be suitable for everyone, over the years, it has gained quite a large following, and from my own experience, the ER4 sound can indeed become very addictive. When I first started with this hobby few years back, I bought lots of IEMs, but in the end, the ER4 prevailed, and I sold off all my other IEMs, not because I thought the ER4 was the best, it’s just because their presentation stood out and couldn’t be found in my other IEMs. I haven’t tried some of the newer IEMs like the Ortofon or Audio Technica’s high-ends, however, in the realm of Westone, Shure, and Ultimate Ears offerings, the ER4 has a very distinct sound.

Nowadays, I own and enjoy a completely different IEM in the Eterna, but the ER4’s instrument separation, quickness, articulation, and presentation of detail brought me to the STAX Lambdas, and I can definitely see some similarities.


Facebooktwitterredditpinterestlinkedinmail

22 Comments

  • Reply June 30, 2010

    Earfonia

    Great review Hadi! Like it a lot 🙂

    From the three, which one has better bass?

    Thanks!

    • Reply July 1, 2010

      Hadi

      Thanks, Earfonia :). I'm partial toward the ER4's bass for its surprising punch and vivid texture (easier to imagine the actual drum being hit) though extension is not the greatest. Some people may prefer the RE0's bass presentation.

  • Reply June 30, 2010

    HC

    Thank you for the nice review Hadi,

    I've read quite a few rave reviews for the RE0 but remained skeptical at best.

    Recently i tried out the RE0, the unit very new but it immediately caught my attention with its clarity. Its like you mentioned, the details are all there but it is smooth, refined and in no way fatiguing after prolonged usage.

    The next thing was the bass, there was much less quantity compared to my Eterna but it is much tighter and detailed. Not to say the Eterna's bass is bad but the RE0 presented it in a whole new way all together and they are definitely not bass lite. It provides just the right amount of warmth and does not flood into other regions of the sound. It is tight yet very gentle to the listener.

    Besides that, i've been trying hard but i could not find anything that really stands out from the sound. Its like they don't have a signature of their own. I think they may have a hint of warmth making their treble sound smooth and relaxing while still retaining all the details.

    Also, i noticed that they are not very efficient but can be played directly from a portable player such as an Ipod and still sound good. I wouldn't say an amp is an absolute necessity but it certainly sounds better with one. I've been pairing them with the Asus Xonar U1. I know its only a budget dac/amp with a usb connection. However they pair up pretty nicely with each other. The Xonar U1 complements the RE0 by not adding anything else but actually refining the way it sounds. Thus giving better bass control, impact and cleans up the overall sound produced.

    I bought them almost immediately after auditioning due to the fact that details are presented so effortlessly yet managing to sound relaxing. You can really just sit back and let them do the rest of the job of presenting the music to you without having to strain your ears to hear the details.

    At this point, some may think that the RE0 will sound boring on Pop and RnB or other types of bassier songs. I was worried about the same at first but after giving them a chance i loved the end result, it was very refreshing.

    In conclusion, the RE0 sounds neutral maybe with a hint of warmth. There is no real emphasis to any spectrum of the sound. Vocals and instruments produced sound are complemented with just the right amount of bass making them sound real and natural. In simple words, everything sounds just as it is, nothing less nothing more.

    Everytime, i try my best to listen with a clean state of mind and not biased towards any type of sound signature. What i've mentioned above is based purely on my honest and humble opinion and is subjective to each individual. I'm open to criticism and please forgive me if i applied any audio terms wrongly as i'm still new and inexperienced.

    Thank you.

  • Reply July 1, 2010

    HC

    Sorry about hogging the comment section, i just wanted to share my opinion and clearly got carried away.

    • Reply June 30, 2010

      Mike

      That’s cool, HC. It’s always good to hear other people’s thoughts on the subject.

      We don’t put limits on the comments section, especially when they are honest and thoughtful such as yours.

      Cheers.

    • Reply July 1, 2010

      Hadi

      Thank you for the comments, HC. I think you made some very well-thought points about the RE-0 ;), thanks for posting it up. Enjoy your RE-0, you have quite a nice combo there with the RE-0 and the Eterna.

    • Reply July 2, 2010

      HC

      Thank you very much Mike and Hadi,

      The Eterna and RE0 seems to compliment each other.

      They are both enjoyable in their own way and i often find myself swapping between them whichever suits my mood best.

      Now eagerly awaiting the long anticipated comparison between the HD800 & T1. =D

      • Reply July 2, 2010

        Mike

        I've finished the HD800 & T1 comparison, and it'll be published tomorrow (Friday) :D.

  • Reply July 2, 2010

    rayk

    Nice review. I have both the RE0s, and now the ER4P. Really enjoy the ER4s over the RE0, they just do everything better while being a little smoother sounding – but that could also be because I get a far better fit with ER4s which go deeper inside.

    Any chance of doing a review of earsonic SM3s?

    • Reply July 4, 2010

      Hadi

      Thanks for the comments, rayk.

      I heard good things about the SM3. No definite plan for now, but we might consider it.

  • Reply July 9, 2010

    jendol

    good review Hadi, I have all three IEMs that you compared here, I prefer er4p over the other two, it has better bass presentation and good seal for my ears. I am intrigue by your impedance adapter, may want to try that and experience how it can improve the sound qualities for the IEMs that I have

    • Reply July 13, 2010

      orz

      Hi; i'm not an expert but this is what I have,

      "impedance adapter" for audio signal works as a "low-pass filter" (http://en.wikipedia.org/wiki/Low-pass_filter), but it's different in my own experience; with low impedance, ER4 has more bass quantity… and so for another phones; if you combine with impedance adapter, your phone's bass quantity would be reduced.

      btw Hadi, would you like to add e-Q7 as comparison for ER4?

      I'm interested on it 😀

      • Reply July 14, 2010

        Hadi

        Yes, that is also what I'm hearing. The 75 ohm impedance adapter takes off some bass quantity (mainly midbass) from the ER4P and the Phonak. Surprisingly, it's harder to notice the difference when I pair the adapter with the Eterna and the DT531.

        Maybe we should let Mike chime in on that :D. I haven't had the chance to listen to the e-Q7.

      • Reply July 14, 2010

        Mike

        Yes, adding a resistor between a headphone and amp will make the sound more bassy. I tried it before with the HD650, but I was using something in the range of 470 Ohms. A 75 Ohms resistor is barely felt.

        The ER4 is quite the opposite in this sense. I really don't know why specifically. Different driver I guess. I also tried the 75 Ohms adapter on the JH customs, and I didn't like the effect. It was more congested with the added impedance.

        Ortofon eQ-7 is totally different sounding than the ER4. The ER4 is superb on clarity, technicalities, separation. The e-Q7 is more midrange oriented, mellow, great vocals, though instrument separation is not so great.

        Cheers.

        • Reply July 14, 2010

          orz

          I've test using a 75ohm adapter to my CK10… results: the high become less edgy; harsh & piercing sound of cymbals and female vocals never bother my hearing anymore…

          Just as Mike says, It's totally opposite of ER4.

          In my own conclusion; if resistor works alone without capacitor, it won't act as filter, neither low-pass or high-pass(mistake on my early statement). I want to catch up more clue about it.

          cheers 😀

  • Reply July 10, 2010

    Hadi

    Thanks, jendol. Impedance adapter may or may not be useful depending on your IEM and/or synergy with your setup. But it's fun and always worth a try since it's relatively easy to get :D.

  • Reply July 22, 2011

    leonsphinx

    Very well said. Really comprehensive, “direct-to-the-point”  review. I own both the REO and ER4 and have the same observations. Hope to see more reviews from HADI

    • Reply July 22, 2011

      Anonymous

      Yes, Hadi does have that kind of clinical precision when he writes. 🙂

  • Reply August 17, 2011

    BDias

    Using the ER4S without proper external amplification is no good.
    Furthermore, I found the review too lengthy at times (to much text to explain simple things), and not that coherent.  For example, criticizing the Etys for fucusing on a narrow frequency bandwidth: mids and highs (hmmm, that’s seems at least 2/3 of the bandwidth !?) 
    I found the ER4S much better than the other two when amplified. It makes a real difference. Not so much width the ER4P. Also, proper ear canal seal is of great importance to get that wonderful bass. It takes some experimentation and it may well be impossible for some to get that seal. That is the real problem with the Etys: if you don’t seal the ear canal as it should you loose bass extension, power and definition and a lot of soundstage. When properly used (correct seal and decent amplification) the ER4S are as good as any top earphone/headphone, except of course, those exotic and very expensive  offerings from Grado, Stax, Ultrasone, Westone and the like…

    BD

    PS: My comment is, of course, biased, but I have seen to many people/critics to jump to conclusions without proper use of the marvelous ER4S.

    • Reply August 17, 2011

      Anonymous

      Thanks, Bruno.

      I think your points are valid, and the ER4S is indeed truly remarkable, and still one of the best IEMs around. I didn’t write this review though, Hadi did, and he is not so much of an amplifier guy.

  • Reply January 2, 2014

    Io

    I hate to say this but really, the ER4S really performs in every way better when amped or at least with a decent source like the fiio x3. I admit the bass quantity is lesser but I find the ER4P bass almost muddy. I agree totally with BDias about the fact that a proper seal is very important. I used it the first time with a bad seal and said it was bassless but remember this is coming from a guy who used the kilpsch s4 which have quite a lot of sub bass thus my basshead needs :d But after a while, I fell in love with the er4s and my friends when he tried it just went ‘yucks, this sucks man, how do you even endure them’ So I guess sometimes it’s just personal preference.

    PS: I insert the er4s seriously deep.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.