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Etymotic Research ER4S

Etymotic Research ER4S Review

Reviewed Nov 2009

Details: Legendary IEM from Etymotic Research, first released more than a decade ago MSRP: $299.99 / manufacturer’s page

Current Price: $223.45 from

Newer ER4SR with removable cable available for $249 from

Specs: Driver: BA | Imp: 100 Ω | Sens: 100 dB | Freq: 20-16k Hz | Cable: 5’ L-plug Nozzle Size: 3mm | Preferred tips: Shure Olives, Etymotic tri-flanges Wear Style: Over-the-ear or straight down

Accessories (5/5) – Large selection of silicone and foam tips, plastic storage case, carrying pouch, two sets of spare filters, filter removal tool, ¼” adapter, and shirt clip
Build Quality (4.5/5) – The tubular are made out of a thick, sturdy plastic. Stock cables are thick, strong, and – if necessary – replaceable
Isolation (4.5/5) – Very deep fit. Etymotic claims a maximum attenuation of 42db, and I believe them
Microphonics (3.5/5) – Can be microphonic when used without the included shirt clip. Hard to wear over-the-ear due to long stem and thick cables
Comfort (4/5) – Have to be inserted quite deeply for ideal seal. The thin housing makes this easier and Foam tips often work great

Sound (9.2/10) – There is just no way not to be blown away with the level of detail these things put out. Unlike the RE0, which let the detail sink in slowly, the Etymotics smack you in the face with it. As a result, they can be very unforgiving of poor source material, as a good studio headphone should be – these are not for collectors of low-bitrate mp3s. The highs are detailed and extended, replete with mind-boggling crispness and resolution. The mids are smooth, detailed, well-placed and very engaging. Tone is neutral and the overall balance is excellent.

The bass has great detail but tends to be a bit thin of note. The ER4S is not bassy by any means, but definitely satisfying for those in search of quality over quantity. Bass texture is superb. The presentation is typical Etymotic – excellent instrument separation, good layering and positioning, but not much in the way of 3D space.

Amping: Not required but will go a ways towards making them shine with portable equipment. Though an mp3 player can drive them to decent volume, it will not unlock their full potential. With a decent amp (such as a mini3), the ER4S really opens the tap on speed and detail.

Value (8.5/10) – Make no mistake – Etymotic’s flagship is still a top-tier IEM 15 years later. The fact that the ER-4S costs $300 to some of the other flagships’ $400+ is a testament to its high value, not low worth.

Pros: Some of the most detailed sound to be had, durable, replaceable cables, unbeatable isolation, 2-yr warranty
Cons: Deep insertion not for everyone, can be difficult to wear over the ear, microphonics can annoy without shirt clip, very analytical sound



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Living in the fast-paced city of Los Angeles, ljokerl has been using portable audio gear to deal with lengthy commutes for the better part of a decade. He spends much of his time listening to music and occasionally writes portable audio reviews across several enthusiast sites, focusing mostly on in-ear earphones.


24 Responses

  1. Thanks for your reply!

    I am still on the fence as to which Etymotic to buy. Do you plan on reviewing their new ER4 XR and SR?

    Keep up the great work!

  2. ER4PT seems to be the better option here as the cable is supposed to be less microphonic than the ER4S, in case you do need to use it outside.

    Other than that you’ll be surprised by how well their sound holds up and chances are you’ll love them just as much as you did back then. It will be a huge contrast to the IE80 for sure, but for music listening there’s not much that can keep up with them in clarity, crispness, detail resolution, etc. And of course the bass is never excessive. I think everyone should hear the ER4 at least once. I’ve owned them twice, and I don’t think I’ll be letting go of my current pair.

  3. Great site! You have such a large variety of phones to contrast and compare, really useful.

    I am hoping you can help me with a future purchase decision. I am looking at the new Etymotic ER4-SR and/or the Hifiman RE400 as an alternative to my Sennheiser IE80.

    While I like the sound of the Senn and love the overall package including ergonomics, bass is a bit too much for my tastes and I would not mind more energetic mid/vocals.

    It has been way too long for me to compare my old Etys vs the Senns. I know they would be quite different but I am not sure how besides less pronounced bass. Any advice you may be able to offer would be appreciated!


    My first IEM was a ER4S from over ten years ago. It was an eye opening experience and I loved them with cable noise the only thing I did not like. When I lost them, I replaced them with Shures which worked out better due to lack of cable noise.

    Nowadays, my listening is usually out of the PC, iphone and ipad (itunes). I also watch movies and some TV using my Senns out of the ipad. Cable noise is much less of an issue as I seldom listen to anything while on the move anymore. If I were to purchase the new Etys or Hifiman I mentioned, it would be for music only as I would use the Senn for TV/Movies. I recently thought I had to replace the Senns as one side was barely audible which got me thinking of new earphones but it turns out I was able to restore them with a good cleaning using hydrogen peroxide.

  4. It depends on what you are looking to see improved over the q-JAYS. At this level most IEMs will be better in some ways, but worse in others, so it really helps to narrow down exactly what you’re looking for.

    From your description of what you like about the q-JAYS, I would only consider the ER4S a potential upgrade – the rest have more “colored”, less accurate sound (in this way or that) and tend to give up at least a little bit of what you like about the q-JAYS, so they’d be a “sidegrade” at best.

  5. Hi Joker,

    I’m really impressed by your knowledge of IEMs. I have Q-Jays and they quickly became my reference: I love how they are detailed, clear, uncongested in the bass and midbass, with that light, accurate and fast bass. I’m looking for a new IEM that would be at least as good if not better than Q-Jays. After many readings, here are the models in contention: HiFiMAN RE-400, VSonic GR07 Classic, Dunu Titan 1 and Etymotic ER4-S. Which one is better compared to the Q-Jays? Thanks.

  6. I haven’t, but from everything I know about the way Etymotic set these earphones up there is no reason for any sound differences.

  7. Hi Joker,
    Just wondering if you’ve compared the two (ER4S and PT with adapter).
    Are they truly identical, or are there still subtle differences?


  8. The IM02 perhaps, but it’s a little dark. The SD-2 will not give you a similar experience to the Etys – too warm and smooth. Not sure about the FitEar. Out of all of these I would have said the DBA-02 mkII is closest unless you can get your hands on something like a VSonic VC1000.

  9. Hello joker – would truly appreciate your advice here.

    I am loving the sound of the ER4S but not the microphonics and to a lesser extent the fit. What is the closest alternative on your mind with similar sound and less cable noise? Tried the Fischer Audio DBA-02 MKII and Hifiman RE400 and do not think these are that close to the ER4S. I am thinking about the Audio Technica IM02, In-Ear SD2 and the Fitear 111?

  10. Sorry, binaural recordings are really not my area of expertise and I’ve never tried the ER-4B. From what I remember Etymotic themselves do not recommend the B for music use (the S gets enough complaints of having too much upper midrange as is) but you might want to shoot them an email and see what they have to say about it these days. Last time I saw the 4B mentioned was years ago.

  11. Hey! I’m interested in your opinion of the ER-4Bs in comparison to these (if you’ve tried them).

    I’ve seen comments floating around suggesting they’re at least as good as the ER-4Ss for music. Would they be that much better than the ER-4Ss for binaural audio anyway?

    I’m trying to decide between these two – for use with both binaural and regular recordings. Getting both is an option but I don’t want to if the difference is marginal. How are the ER-4Bs for music, and how are the ER-4Ss for binaural?

  12. They can take some EQing as long as you’re not trying to radically change the sound. They will never be basshead earphones, but if you’re just trying to sculpt the response a bit here and there to suit your needs, no problem.

  13. That’s an interesting question because the ER4S and W40 are pretty much the opposite extremes when it comes to sensitivity/efficiency. The W40 is well above average while the ER4S is one of the least efficient IEMs.

    Rough guesstimate, I’d say you need at least 50% volume headroom on your iPhone, meaning that if you normally use your W40 below 50% volume you should have enough room to compensate for the lower efficiency of the ER4S.

    There is also the newer ER4PT. If I’m not mistaken, it also comes with the 4S adapter, which means you’re getting the best of both worlds.

  14. Hi Joker,

    Love your work! Right now I have Westone W40s, but the fit is driving me crazy — one keeps falling out. Have been through all the different tips, Complys, etc. So have been thinking about Etys again, perhaps the fit will do me better. I don’t really crave the Westone warmth — last thing I had was RE400 — but do worry about output level a little. I use IEMs for iphone, and don’t want to lug an amp around with me. Do you have any thoughts on output difference between ER4s and W40s? Or any other commentary? Thanks!

  15. It’s quite a small difference, but par for the course in the diminishing returns land of higher-end audio. You never get double the performance, or anywhere close to it, for double the money. If I were you I’d skip the upgrade, but I’m sure some would disagree.

  16. Hi Joker! I’ve had the HF5/HF2 for eight years now, and I’ve just sent my last pair back to Etymotic for the special purchase pricing (cable had a split originating at the jack). I can replace my HF2s for around $80, or get the ER4 for around $180. Do you think that the step up in sound will be meaningful for a $100 difference, especially considering that I will be using them with a Sansa Clip+ without amping?

  17. The ER4-P is the unequalized version of the ER4. This gives it a lower impedance that makes it play somewhat louder with a bass boost on lesser lower powered players or amps that have a lower voltage at the headphone output. Adding the “S” cable wild add a passive equalizer network in the cable that flattens the frequency response but also raises the impedance of the earphone so it plays at lower volume and needs more amplification for a louder sound. One can buy a set of ER4 and can have it both ways. I have had numerous sets of the ER4 over 20 years and am amazed it is still around and is still a standard for me and obviously others as well regardless of what else is available. I have purchased a few expensive custom IEMs for high dollars and was nothing but disappointed after having lived with these for years. If you are looking for good sound you can’t go wrong with these. Even the lower bit rate mp3s will sound as good as they can and there is no point in trying to gloss that over but rather to learn where the limit of different mp3 levels are and compress accordingly. A mp3 encoded at a high bit rate will hold up very well with the best playback equipment and sound great with the ER4.

  18. The PT is identical except the cable has ~75 ohms less resistance. The sound is very close between the two but the ER4S has always been recommended as the more accurate one, so it’s the one I’ve stuck with.

    You can go from the PT tuning to the S tuning by adding an inline impedance adapter.

  19. What I meant is, balanced and accurate headphones like these make it easiest to pick up on things like compression artifacts in low-bitrate mp3s and poor mastering in general. If you have a lot of those types of tracks and don’t want to hear that stuff, get less revealing headphones.

  20. I’m pretty new to high-end IEM’s and these look really nice to me. What I don’t understand is what does “these are not for collectors of low-bitrate mp3s” mean? I mostly listen to music on my iphone and my macbook and i listen to a whole range of genres, will they not be good for me? Wouldn’t you want analytical sound?

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