Etymotic ER4SR

Link to my review and measurement index thread where one can also find a full review overview, more information about myself as well as my general-ish audio and review manifesto: https://www.head-fi.org/threads/956208/

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I only give full stars. My ranking/scoring system does not necessarily follow the norm and is about as follows:

5 stars: The product is very good and received the "highly recommended" award from me.

4 stars: The product is very good and received the "recommended" award from me.

3 stars: The product is good/very good, but not outstanding/special enough to get any of my two awards. ["Thumbs Up"]

2 stars: The product is only about average or even somewhat below that and somewhat flawed/flawed in some areas. [neither "Thumbs Up" nor "Thumbs Down"]

1 star: The product is bad/severely flawed to outright bad. ["Thumbs Down"]

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Etymotic ER4SR


Source:

Review sample.


Miscellaneous:

Really nice unboxing experience with many accessories such as an amply large, protective carrying case, several different ear tips, a “certificate of performance” that shows the individual in-ears’ frequency response, channel matching, serial numbers, sensitivity and measured total harmonic distortion.

“SR” stands for “Studio Reference”.

While the ER-4S’ shells were made of plastic, the ER4SRs’ are made of metal and appear visually subjectively more premium. The unique serial number is still engraved into each shell.
Build quality seems to be very good.

Instead of the 2-pin connectors similar to the ones from Sennheiser’s HD 6x0 series headphones used on the ER-4S, the ER4SRs’ cables now come with MMCX connectors that are rotation-locked wherefore they seem quite reliable and durable.
The new cable is definitely an improvement over the older one as it is more flexible and softer while it still appears sturdy. Another good thing about it is that it has now finally got an incorporated chin-slider.
Although the y-splitter doesn’t contain any resistors anymore (the crossover components are now inside of the shells instead), it has still got that cylindrical shape as an homage to the previous generation where the bulky shape was necessary to carry the resistors (and in case of the ER4B also the capacitors).
On the other hand, the side indicators are now more difficult to find as there is no red dot on the right hand side’s connector anymore.
Twisted conductors above the y-splitter.
Rather high microphonics when worn down, but that can be fixed by guiding the cable over the ears and using the chin-slider (or alternatively using the included shirt clip).

One Balanced Armature driver per side.




Sound:

Largest included triple-flange silicone tips, modified so that they create a seal in my large ear canals while still maintaining the original ear tip length (achieved by cutting off the smallest flange and putting it onto the nozzle first, followed by the remaining double-flange rest of the tip).

Tonality:

Flat studio neutral; lifeless and uncoloured.

The ER4SR, to my ears when performing sine sweeps, listening to noise signals, music and spoken word, just sound as they are advertised – studio reference neutral flat.
Just like my ER-4S, the new ER4SR just don’t have any colouration at all to my ears and come the closest to my personal perception of uncompromised neutrality, and are therefore the flattest and most lifeless, most uncoloured, most accurate and realistically tuned in-ears that I have ever heard, wherefore they, along with my ER-4S, are also by far my favourite choice for serious music listening from my CD rig; their tuning just seems to match my ears’ HRTF extremely well wherefore I choose them over my Ultimate Ears Reference Monitors, the Ultimate Ears Reference Remastered to-go and my InEar ProPhile 8, three sets of in-ears that are among the most neutral on the market but in comparison still tuned more for a “natural neutral” instead of “uncompromised studio neutral” tonality, purely based on my personal tonal preferences.

Generally, there is not much that I could really think of about writing here, since the mostly audibly flat and lifeless, neutral tuning could be more or less summarised in just one sentence.

The bass is just flat without any sort of lift and extends flat down into the real sub-bass without any real roll-off. Etymotic, just as with the ER-4S. No warmth, no body, but definitely not lacking – just uncompromised flat.

The midrange is just generally flat and direct, without any of the relaxation dips in the upper mids that is found on almost any other set of in-ears, wherefore the ER4SR are quite merciless here and purely raw, without trying to create any sort of recession to create an even slightly laid-back fatigue-free long-term listening effect.
While, to my ears, the ER-4S still showcase just a little of lift in the presence range, this area has been toned down very slightly on the ER4SR wherefore they sound even a bit more accurate to my ears here.

The treble, just like on the ER-4S, is simply among the most realistic and evenly tuned regardless of price, wherefore the ER4SR manage to create an incredibly realistic, accurate response here as well.
The only area, when performing sine sweeps, that is just a little below neutral in quantity to my ears, is the one around 7 kHz, but this is nothing that’s really audible when listening to music.
Extension past 10 kHz is good and not lacking to my ears.

To summarise, the ER4SR are truly worthy successors to the ER-4S and come extremely close to my personal perception of an uncompromised, lifeless, uncoloured, flat studio neutral tuning with an excellently realistic and even tuning that is rarely achieved by other in-ears, especially in the treble. Therefore it is no surprise that I personally really love them.

Frequency Response:


ER-4S-Compensation

The ER4SR were measured with the non-modified triple-flange ear tips in both graphs as I did not save the other measurements and didn’t bother to re-measure them. Due to the resulting slightly different insertion depth into the coupler, the graphs shows a bit less upper treble quantity than they would actually have, as it’s really just the upper mids/presence range where the ER4SR differ slightly from my ER-4S.


ProPhile 8-Compensation

Resolution:

Very high. Probably the best single-BA implementation that I know of, and superior to some multi-BA models.
Typically for a single-driver design, coherency is perfect.
Even distribution of the resolution across the whole frequency range.

Nimble, fast, tight and controlled bass. High quality. Outperforms some of the other single-BA in-ears in terms of speed and tightness, although ultimately not as tight and controlled as some multi-BA implementations when pushed to the limits by the recording; comparable speed but a little softer in comparison. There are, however, some multi-BA implementations that are noticeably softer and slower – so absolutely nothing to criticise here and about the most technical single-BA implementations I know of in the lows.

Very high midrange resolution and speech intelligibility without “cheating” by presence range elevations found implemented into some w-shaped in-ears’ tuning. Very authentic.

Excellent transient response and precise note separation in the high frequencies. Highly natural as well thanks to the very even treble response.

It is generally remarkable what the ER4SR manage to put out in terms of tonal range/extension, bass quality, resolution and authenticity – just like their predecessors, they show that a well-implemented and -tuned quality single Balanced Armature driver doesn’t lack behind its similarly priced multi-driver competitors.
In some categories, there are multi-driver in-ears (such as my UERM and ProPhile 8) that can somewhat beat the Ety in terms of partial resolution or bass speed, transparency and control when the recording is extremely demanding, however there are very few in-ears at this price point that deliver such an excellent overall package where nothing lacks behind – there is really hardly any flaw in terms of resolution.

Soundstage:

Neither the largest nor the smallest. “Averagely large”, as it usually the case with a flat neutral tuning without any strategically placed elevations or recessions.

Authentic and three-dimensional with just as much depth as spatial width to my ears.

Precise imaging without any blur/fog. No bleeding of single instruments/tonal elements into each other. The ER4SR even manage to render some of the perceived “empty space” around and between them really well; to my ears even a little better than the ER-4S since the newer generation in-ears remain a bit better separated and more controlled sounding with more complex and fast recordings.

Generally convincing and realistic.

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Comparisons:

Etymotic ER-4S:

Only very small differences when it comes to tuning: the ER4SR are slightly less forward in the presence range and will therefore appear slightly less fatiguing over time; to me they are even a little more realistically tuned here than my ER-4S. Slightly less level around 10 kHz as well.

Pretty much equal when it comes to resolution. In comparison, though, the ER4SR appear to be just a slight bit softer in the lows, but as a result also just a little more visceral.

To my ears, the ER4SRs’ soundstage appears to be just a touch wider than the ER-4S’, with a slightly cleaner imaging (instrument separation), which is mostly audible with faster and more complex recordings.

InEar ProPhile 8:

To my ears, the ER4SR represent more of a “sterile studio reference neutral” tuning whereas the ProPhile 8 fall more into the range of being “naturally neutral” tuned.

That said, the ProPhile 8 have around 3 dB more bass than the ER4SR and sound warmer in the fundamental range and lower mids, but are a bit less “warm” than the ER4XR and have also got slightly less bass.
The ER4SR are slightly more forward/intimate sounding in the mids whereas the ProPhile 8 present the middle frequencies in a comparatively more relaxed way due to the more recessed presence range, but with still accurate timbre and no audible colouration.
Both are very even, realistic and accurate in their treble reproduction, which is something not too many in-ears achieve.

In terms of resolution, precision, bass speed and tightness, the ProPhile 8 are ultimately ahead, which is the most audible during very fast and complex, dense music, but not as strikingly obvious otherwise most of the time. So to say, the ProPhile 8 don’t yet “cave in” when the ER4SR already start to do.

Regarding perceived soundstage, that of the ProPhile 8 isn’t even all that much larger to my ears but only somewhat, but as with the resolution, the In-Ear in-ears are ahead when it comes to imaging precision and remain cleaner, better separated when the track is densely arranged and/or very fast.

Ultimate Ears Reference Monitors:

In terms of flatness and accuracy, I hear the ER4SR as superior to my UERM that have about 3 dB stronger bass quantity, are more relaxed in the presence range in comparison, and brighter past 10 kHz due to the peak that they have there, and which also makes their treble response come across as ultimately less even and realistic compared to the Etymotic (and UERR to-go), although that’s criticism on a rather high level.
As a result, the ER4SR are even more critical to the recording and even less forgiving, and more sterile sounding (which is something that I consider a very positive aspect while others may not).

While I prefer the ER4SRs’ even flatter, less forgiving, more sterile tuning, when it comes to bass speed, control, micro details and note separation, I definitely perceive the UERM as audibly superior, as they have more detail headroom for the recording to pushing them to their limits.

The same as for the resolution can be said about the soundstage that appears to be a good bit larger than the ER4SRs’ and “gives in” less early in comparison when very dense and fast arrangements are played back.

Shure SE425:

The Shure are somewhat more on the mid-centric side of neutrality compared to the Etymotic.
The SE425 are comparable to the ER4SR in the bass department but have got slightly more upper bass and lower root quantity. To my ears, the Shures’ midrange is somewhat more emphasised.
The SE425 have got somewhat less level in the highs, however just slightly. They start to roll of very early, though, even below 10 kHz, whereas the ER4SR extend well above that.

The ER4SR resolve better (higher detail retrieval and transparency) and seem to have the cleaner transient response.

The Shures’ soundstage is quite small and congested in comparison to that of the ER4SR, and the Ety also feature the better instrument separation.

Etymotic ER2SE:

Highly comparable to almost similar tuning, with the ER2SE having minimally more bass quantity, minimally less presence range quantity, and slightly less level at 10 kHz. The ER2SE, unlike the ER4SR, are closer to neutral around 7 kHz, though, when performing sine sweeps.

In terms of technical perception, the dynamic driver Etys are just a smidgen behind the BA Etys to my ears when it comes to ultimate note separation, but this only shows rarely when the in-ears are stressed by very busy, dense and bast sound material. Most of the time, they are remarkably close to the point of being near-indistinguishable.
Slightly “softer” bass presentation compared to the BA Etys but on its own very tight and controlled. Attacks and impact better/easier perceived when compared to the single-BA Etys.
In direct comparison, the single-BA Etys appear to have a bit of “grain” in the midrange compared to the dynamic driver Etys that do not.

Larger perceived soundstage than the single-BA Etys and highly precise as well, but starts to become “foggy”/gives in earlier with spatially very crowded, densely arranged tracks with many tonal elements at the same time, wherefore the ER4SR are my choice with spatially more crowded, more demanding recordings/arrangements.

Etymotic ER4XR:

The XR have got ca. 3 dB more quantity around 100 Hz and ca. 4 dB more than the SR around 50 Hz, and a little less than 5 dB at 30 Hz – not much, but enough to make them sound a bit bassier and have a bit more perceived body/texture and a little more lower midrange/fundamental range warmth in comparison, albeit without affecting the midrange balance.
The XR that I have on hand are slightly more relaxed in the presence range, but have got a bit more quantity around and above 10 kHz (definitely not to degree of an emphasis, but just enough to make them have slightly more perceived subtle super treble sparkle/”air”).
Generally, the difference is definitely mainly in the lows.

Both sets of in-ears are equal to me when it comes to resolution and bass quality, with the exception that the ER4SR, when compared directly to the XR, sound ever so slightly cleaner in the lows.

Both have got an almost identical soundstage reproduction, with the ER4XRs’ being ultimately just ever so slightly less deep and minimally less precise in terms of separation in direct comparison.




Conclusion:

Highly Recommended.

Uncompromised, flat, uncoloured, lifeless “studio neutral” tuning with a flatness (especially in the treble) and realism that is only rarely achieved.
High technical performance as well (ultimately below that of my UERM and ProPhile 8, but the ER4SR, as a whole package, still outperform many other multi-driver in-ears in the 500$ range or are at least similarly precise when it comes to technicalities, and moreover have that uncompromised flat neutral tuning in addition).

As a result, together with my ER-4S, they are also my personal favourites for serious CD listening.


Photos:

Got these as a upgrade when my ER4PT cable broke. Never expected these blow me away despite being DF flat and BA based, But after owning them for 2.5 years. I keep getting surprised at how detailed they are when trying past albums in my collection, many sound like if I was given a remastered version.

Never understood the "Single BA" claim since the bass goes super deep and the super fast decay really helps with keeping up with fast metal/electronic. While any dynamic headphone seems hit a wall and the bass just sound like a muddy mess. With EQ done you can make fit closer to Etymotic target, 2.7db at 7.5KHz & -2db at 1.6KHz really opens them up further. With 6db bass boost it dosen't hurt the clarity it just adds more meat and sounds more stable than the ER2SE with same boost.


Total steal for a sub $500 Universal IEM.

 
 
 

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Preamble:

Let me begin this review with a rather unusual introduction:

Truth to be told, I have not much in mind what to exactly write here. I don’t even have a strict plan on what to write overall other than “it sounds flat, neutral and uncoloured” at the moment. This is a challenging review, a very challenging one actually.
Usually for any headphone, in-ear or earbud, I have a clear structure in my mind of what to write. With the models that I own for a few years, it is quite easy and other than performing sine sweeps and directly comparing the in-ear with some competitors, the whole review usually already exists in my head. And also with samples that come in, I usually have a clear order on what I do prior to starting the review and the rest is then quite easy to finish, as I then already know what to write in the “Sound” section.

With one in-ear that I can confidentially say I love the most among all other models and that I own for round about three years now, which is a pity as I should have “discovered” it way earlier, which unfortunately didn’t happen as it didn’t get any mention at all in the German online audio communities, it was quite different: from the first word written to completing my review, it took me almost a
whole year although I already owned it for more than a year at this time. There was just emptiness in my head concerning what to write.
The thing is that it is fairly easy to review a headphone that deviates from purely neutral sound (which certainly isn’t meant in any negative way here), as there is plenty of what to write about. Even in-ears that tend to go into a very neutral direction but aren’t 100% flat are rather easy to describe. Writing the review for that particular in-ear in German however was not easy, as it sounded about as neutral as it could get and didn’t even add the slightest bit of its own character to the sound – it was just flat and lifeless (both meant in a good way here), however the problem with this is to properly put it into words. But eventually I had finished that review and was happy with the result and what I’ve written (however, I have never translated it into English, although I had thought about it not just once).

Now history seems to repeat itself – at least this review right here features the successor of that particular in-ear, and the in-ear monitor that is reviewed here is supposed to be even a wee bit more flat and neutral than its predecessor based on the diffuse-field target.

You will of course know by the title that I am talking about the Etymotic ER•4SR and that that German review was about the ER•4S, but without reading the title and just the preamble, you might have probably guessed the models as well if you are at least remotely familiar with Etymotic Research that was founded in 1983 in the USA by Mead Killion (http://www.etymotic.com/about-us/interview-with-mead), a man that I highly respect.
In the early 1990s, the “grand daddy” of neutrality, as I like to call it, was born, the Etymotic ER•4 series, a series of in-ear that was manufactured for more than 20 years with just quite minor cosmetic changes, mainly concerning the cables.

When I read on the CES exhibitor page in late 2015 that Etymotic Research would be there as an exhibitor and also present an updated line of their ER•4 series, you can believe me that I was quite excited.
And so it came that the ER•4SR and ER•4XR were released as the successors of the ER•4S and ER•4P, with the first being just a small facelift on the sound side, whereas the second turned out to be more than just a facelift of the ER•4P, delivering what many customers were craving for – an Etymotic that still sounds balanced and neutral but carries just a bit more bass and warmth than the ER•4S.

And while the sound signature of the ER•4SR (SR by the way stands for “Studio Reference”) is greatly identical to the ER•4S’s (which is not much surprising, as bringing something that is already very close to a perfect diffuse-field flat target response even closer to it is not easy), it is internally and externally different and doesn’t only feature a different Balanced Armature driver inside along with a higher sensitivity and lower impedance, but is also equipped with a new cable that is now using MMCX connectors on the in-ears’ side instead of the 2-pin connectors that were also used for Sennheiser’s HD 6X0 series.
While the “old” ER•4 series used the same drivers in the whole product range and only differed in terms of cable impedance (with the exception of the ER•4B that also had capacitors inside) which allowed the ER•4P to be turned into the ER•4S by just adding an impedance adapter, the new ER•4XR (XR stands for “Extended Response”) is using different BA drivers than the ER•4SR and is a separate in-ear that cannot be turned into the SR version like that.


After this quite long introduction, all I want to say is that I’d like to invite you to read the rest of my review in that I will try to elaborate how the ER•4SR sounds and what makes it so great in my opinion.


Before I continue, I want to give out a huge “thank you” to Etymotic Research who agreed to send samples of the ER•4SR and ER•4XR to me free of charge to write these honest reviews that represent nothing less than my honest and unfiltered opinion on the products.


PS: If you can see bricks, steps and other artefacts in the very dark sections of my photos that aren't on the original files - congratulations, you have just discovered what online photo compression looks like.


Technical Specifications:

http://www.etymotic.com/consumer/earphones/er4-new.html
MSRP: $349
Frequency Response: 20 Hz - 16 kHz
Transducers: high performance, Balanced Armature micro-drivers
Noise Isolation: 35-42 dB
Impedance (@1kHz): 4XR (45 Ohms) 4SR (45 Ohms)
Sensitivity (@1 kHz) SPL at 0.1 V: 4XR (98 dB) 4SR (98 dB)
Maximum Output (SPL): 122 dB
Cable: 5 ft, detachable
User Replaceable ACCU-Filters: Yes
Warranty: 2 Years
Custom-Fit Option: Yes


Delivery Content:

The in-ears arrive in a nicely designed packaging that contains a large zippered storage case that has got enough space for the in-ears as well as an audio player/DAC/amplifier inside, and has even got pockets to store the included accessories which are a 6.3 to 3.5 mm adapter, a shirt clip, spare ACCU filters with a removal tool, two pairs of small/medium triple-flange silicone tips, two pairs of medium/large silicone tips and two pairs of grey foam tips. What I find really nice is that a “certificate of performance” that shows the frequency response, channel matching, serial numbers, sensitivity and total harmonic distortion of both ear pieces, is included as well.
 

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While I wouldn’t mind if a smaller storage pouch like the one that came with the ER•4S was included, too, the one included isn’t much larger than a Pelican 1010 case which is still quite reasonable in size.


Looks, Feels, Build Quality:

Compared to the previous generation where they were made of plastic, the new ER•4 series’ housings are made of metal and gain a more premium appearance due to this. The unique serial number is still engraved into each individual housing, but now there also is the model-specific labelling that tells you which in-ear you have.
The old 2-pin connector known from Sennheiser’s HD 6X0 series has been dropped and now there are rotation-locked MMCX connectors instead. They seem quite reliable, however only time will show how reliable they really are (in a scenario where I don’t remove the cable unless I have to).
 

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The cable is an improvement over the older one, as it is more flexible and softer while it is still sturdy and looks overall quite similar. What I really like about it is that a chin-slider has finally been incorporated, compared to the ER•4S where it was unfortunately missing.
Although the y-splitter doesn’t contain any resistors anymore, it has still got that cylindrical shape as an homage to the previous generation where the bulky shape was necessary to carry the resistors (and in case of the ER•4B also the capacitors).
 

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I’d personally like coloured side markers on the cable, because apart from the small black letters on each side, there are none. Knowing that the old ER•4 generation underwent some cosmetic changes, I wouldn’t be surprised though if the side-markers were changed some time in the future.


Comfort, Isolation:

The ER•4 series in-ears need to be inserted really deep, passing the ear canals’ second bend, else the sound is likely incorrect. This might be irritating or even slightly painful at first if you aren’t used to in-ears that are inserted as deep, however I have no problem with this and don’t experience any pain at all.
Best insertion works with the cables down, so you automatically know when you have reached the correct insertion depth. Right afterwards, the cable can be guided around the ears, which is also how I do it, which will also audibly reduce cable noise (microphonics) to a tolerable level (less microphonics are barely possible because of the deep insertion, however with the over-the ear wearing style and using the chin-slider, they can be reduced well).
 

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I have got quite large ear canals wherefore I had to modify my ER•4S’s tips in order to get a consistent seal with it.
The new ER•4 series in-ears however come with ear tips that have got the same dimensions but are made of a different material. To my surprise, I get the large ear tips to seal in my large ear canals with them, as they are more stable and also stickier. Nonetheless, I still need to adjust the fit from time to time, wherefore I modified the tips the same way I did with the old ones (I cut the smallest flange off, put it on the nozzle first and then attached the now double-flange tip to it – with this, I get a very good seal in my large ear canals but the length of the ear tips remains identical to prior to the modification).

If properly inserted and sealed, noise isolation is very high.


Neutral = Neutral?

Before I head over to the “Sound” section of my review, I will take a short look at the theory and research of neutrality with headphones and in-ears and give a very brief introduction to this topic.

With loudspeakers in a room, it is quite easy to define what a measurably neutral frequency response should look like, as it is supposed to be a flat line. The case is different in the headphone realm: A headphone or in-ear that would measure exactly like a flat speaker in a raw measurement would sound different directly at the eardrum – this is because our ears, ear canals and upper body amplify certain areas of the frequency range, which is a totally natural thing. With headphones and in-ears, these natural reflections and amplification disappear as the source of sound is directly at the ear, respectively inserted into the ear, wherefore the ear canal is closed on both sides and the “Open Ear Gain” disappears.
To imitate the natural amplification of the lack of this Open Ear Gain, a headphone should ideally show a boost in this area of the frequency response when an uncompensated frequency response chart is viewed (roughly speaking, the boost should be seen between ca. 200 and 15000 Hz, with the climax around 2.7 kHz with an elevation of around 15 dB here). Measured directly at the ear drum, this would result in a perceived flat and neutral frequency response (important and related key words on this topic are “HRTF” and “Open Ear Gain”).
Of course the ear anatomy will slightly differ among individuals, wherefore the perception of the averaged diffuse-field target might not be perceived equally by everybody, especially when it comes to the perception of the upper midrange and presence area, wherefore some people perceive an in-ear that measures flat in the presence area and lower treble after subtracting the Open Ear Gain from the raw measurement as exhausting or even shrill whereas many other individuals hear the same frequency response as acoustically flat and neutral.
Most frequency responses of headphones one can see in magazines and large online sites are therefore usually shown with the diffuse-field compensation already subtracted from the raw measurement and show the frequency response that is perceived directly at the ear drum instead of the raw measurement that can be confusing at first if one is used to loudspeaker measurements.

Apart from the existence of the Open Ear Gain, there is one thing that has caused some inconsistency among researchers about what the ideal neutrally perceived frequency response for headphones should be: Listening to music, we don’t only hear the sound waves that reach our ear drums, but also feel the mechanical vibration/body-borne noise with our whole body, especially at higher volume levels. With headphones however, there is no mechanical vibration/body-borne noise anymore, wherefore some people might find a diffuse-field neutral headphone to sound too thin although a neutrally measuring loudspeaker in a highly treated might not perceived this way by the same person. Some people and researchers are therefore convinced that the lack of mechanical vibration/body-borne noise when listening through headphones should be compensated by adding a slight (!) emphasis to lower notes in order to get a headphone to be subjectively perceived to sound equally neutral as a neutrally measuring loudspeaker.

As one can see, the perceived neutrality with headphones is a topic where there is no 100% unity even among famous researchers upon what the ideal frequency response should look like, and of course the individual ear and body anatomy might as well contribute to individual variance although major researches have come to the same conclusion of what the averaged HRTF looks like.


Sound:

Sources I used for listening were mainly my iBasso DX90, the Cowon Plenue M2, and my Chord Mojo plus Leckerton UHA-6S.MKII stack with the Shinrico SHD5 as source device.

To get the correct sound, the correct eartip length and correct insertion depth are important. That the end of the sound outlet should be inserted very deep in one’s ear canals, past the second bend, should be clear after he “Comfort, Isolation” section.
The correct length of the ear tips however is at least just as important. As described further above, I am using the ER•4SR with the largest included triple-flange tips that I have modified to seal well in my large ear canals while maintaining the same length as before. With other tips (single-flange or Shure Olive Foamies that are shorter than the Etymotic ear tips), the sound was not as accurate in my ears and deviated from the correct sound that I am only getting with the correct insertion depth and ear tip length (solely Etymotic’s cylindrical foam tips generate pretty much the same sound as the stock triple-flange tips in my ears).

Tonality:

The ER•4SR is so neutral and flat over the whole audible spectrum that many other in-ears sound audibly more coloured in direct comparison when listening to music and sine sweeps and that some other in-ears that are described and advertised as neutral don’t sound as neutral in comparison (however, see the “Neutral = Neutral?” paragraph further above; it is (usually) not the case that other manufacturers don’t know what they are doing when creating the sound of an in-ear, however they might have a different view on (subjectively perceived) neutrality with headphones, or have different target responses in mind when tuning an in-ear, or don’t go for a 100% flat response to make the sound a bit more pleasant for a greater target group).

But first things first: Etymotic’s ER•4SR is both measurably and audibly extremely neutral and flat and seems to harmonise very well with my ears’ HRTF.
The mild lift in the presence range is just barely there in my ears when listening to music or sine sweeps, and definitely not as fatiguing as some people perceive it. The midrange appears a little more direct though and also slightly more exhausting over time compared to an in-ear that is on the more laid-back side here.

Listening to sine sweeps, noise and music, this single-BA in-ear is the most even, flat and coherent sounding in-ear in my ears. From the sub-bass to the upper treble, there is no waviness at all, and there are no narrow or wide dips or peaks either except from a minor lift in the presence range around 2-3 kHz and a slight recession around 7 kHz that is however hard to make out. Due to this, the timbre is extremely natural and all instruments as well as vocals sound ideally neutral and straight to the point uncoloured to my ears.
 

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Even without (nerdy) sine sweeps but just music, the Etymotic in-ear demonstrates how uncoloured and flat sound can be from an in-ear. I would also consider it as being lifeless (in a good way as in that it doesn’t add its own character to the sound but just plays back what is on the recording without adding any extra flavours). Due to its extremely high flatness, it will also easily show when a bit too little or too much of a certain frequency was added in the master of a recording, which also makes it to a great professional tool (that it actually mainly is).
Of course, the seal along with the insertion depth and ear tip length need to be correct for this, and the sound also has to match one’s personal HRTF that might vary a bit among individuals. Lucky for me, it seems like the ER•4SR’s frequency response, just like my beloved ER•4S’s that sounds widely similar, matches my ears’ HRTF very well.

I would bet money on that the ER•4SR will sound too boring, sterile and flat for a high number of people compared to the majority of in-ears on the market (including those that are tuned to go into a more balanced direction).
This extremely high accuracy is what makes the ER•4SR so great and also a worthy successor of the legendary ER•4S that sounds most widely similar.

Resolution:

That it doesn’t necessarily need a multi-BA setup to get great sound quality in the price range around $500 is what Etymotic has showed once again with their new in-ears. The sound is very nimble, fast, coherent and very resolving as well, something that one probably wouldn’t expect from a single-driver setup.
Especially commendable is the ER•4SR’s excellent transient response over the whole frequency range – everything sounds in place and doesn’t lose direction at any frequency band.

It is remarkable what the ER•4SR puts out in terms of tonal range/extension, bass quality, resolution and authenticity – just like its predecessor, it shows that a well-implemented and -tuned single Balanced Armature driver doesn’t lack behind its similarly priced competitors.
In some categories, there are multi-driver in-ears that can somewhat beat the Ety in terms of partial resolution or bass speed, however there are very few in-ears at this price point that deliver such an excellent overall package where nothing lacks behind – there is hardly any flaw in terms of resolution.
 

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Besides the excellent coherency and authenticity, the ER•4SR puts out a very detailed and well-separated treble along with a highly transparent midrange. Its bass response is really fast as well, and it outperforms some other single-BA in-ears as well in terms of speed and tightness. Compared to some of the higher-priced multi-BA in-ears though, while the bass speed might be comparable, the ER•4SR’s bottom-end will appear a bit softer but nonetheless highly controlled and therefore a bit more visceral.

Soundstage:

The soundstage surely isn’t the largest in all directions, however just as with the ER•4S, I have never perceived it as small or congested at all but averagely large with an excellent width-to-depth-ratio and a perfect spherical and three-dimensional illusion.
Instruments are very precisely placed in the imaginary space and layering is precise as well, without any fogginess. Separation is really good as well and instruments don’t blend into each other but are separated with even some empty space between and around them. In this regard, it has even slightly improved over the ER•4S in my ears, as with more complex and faster recordings, the ER•4SR sounds a bit better separated and caves in less but remains very controlled.

Personally, I really love the ER•4SR’s spatial presentation, as it manages to convince me in terms of authenticity and three-dimensionality while not being extra wide or deep. Therefore, the Etymotic also counts to my personal favourites when it comes to soundstage.

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In Comparison with other In-Ears:



Ultimate Ears Reference Monitors:
Compared to the Etymotic, the UE is a bit less of a reference when it comes to absolute flatness, even though it still sounds very neutral (Ultimate Ears also said that the UERM was tuned for subjective neutrality, so things like the compensation for the lack of mechanical vibrations might have been important in the tuning process as well).
In comparison, which can also be heard when listening to sine sweeps alone with it, the UERM has got around 3 dB more bass than the Ety and the more forward lower fundamental range wherefore it is a little warmer there. Except for the presence range that is a little forward on the ER•4SR, both sound comparable to me in the midrange. Going up with the sine sweeps, I can hear a dip in the UERMs’ middle treble along with a narrow peak around 10 kHz that can sound a bit harsh if a single note hits it exactly.
So especially in the treble, the ER•4SR is more linear and even in comparison, wherefore it also sounds more authentic and realistic here.
In terms of bass speed and control, as well as detail retrieval and instrument separation, the UERM is ahead, however the difference in terms of instrument separation has become smaller than compared to the ER•4S.

Etymotic ER•4S:
The ER•4SR’s cable is softer and more flexible. It has also finally got a chin-slider above the y-splitter wherefore microphonics can be lowered, too. And while the new silicone tips have got the same diameter as the older grey ones, they seal easier in my ears and I probably wouldn’t even necessarily have to modify them.
The ER•4SR’s sensitivity is higher wherefore it needs less voltage to reach the same listening level as the ER•4S.
In terms of sound, you will only find small changes. Both have got the same flat, diffuse-field neutral bass response. The ER•4SR has got the slightly less forward presence range wherefore it will appear to be slightly less fatiguing over time. The ER•4SR has also got slightly less level around 10 kHz. My ER•4S has got somewhat more quantity above 10 kHz, wherefore it will be perceived as a tiny bit brighter and further extending (it has got a bit more subtle glare above 10 kHz). Parts of that could of course also be due to slight manufacturing tolerances instead of actual tuning differences.
When it comes to detail retrieval, both are pretty much on the same high level to my ears. The only real difference is that the ER•4SR’s bass appears to be slightly softer in comparison but also a little more visceral as a result.
In terms of soundstage, ER•4SR’s appears to be a touch wider than the ER•4S’s in comparison. I’ve always perceived the ER•4S as authentic and three-dimensional when it came to spatiality, and the same goes for its successor that I hear as having the somewhat cleaner instrument separation between the two which becomes the most obvious with faster and more complex recordings.

Noble Audio SAVANNA:
The Etymotic’s bass is flatter (around 3.5 dB less) in the midbass, upper bass and lower root in comparison, however both have got about the same sub-bass quantity. The Noble’s mids are just slightly darker in comparison. To my ears, the SAVANNA’s treble is just slightly less present than the ER•4SR’s but almost identically even and coherent, which brings it extremely close to the Ety’s evenness and naturalness in the treble (in fact, the SAVANNA would even be identically even in the treble to my ears if cymbal crashes decayed slightly less quickly).
The SAVANNA has got the somewhat larger soundstage in all directions and the slightly cleaner instrument separation.
Overall, it is about as even, realistic and coherent sounding as the Etymotic but with a bit more bass kick.

Etymotic ER•4XR:
Being used to speakers, in-ears and headphones that head into the flat/neutral direction, I never found my ER•4S or the ER•4SR to lack bass or sub-bass at all, it just wasn’t emphasised and spot-on flat to the diffuse-field target response. Some people however, who really liked the ER•4 series’ midrange and treble, wanted a little more bass impact at times. And this is exactly what the ER•4XR gives: basically the same sound signature as the ER•4SR, however with a bit more bass.
Beginning in the lower root, the ER•4XR’s bottom-end evenly rises towards the sub-bass where its climax is at. Nonetheless it is no bassy in-ear at all and just adds a bit more level to make those who want a bit more compensation for the lack of mechanical vibrations happier.
According to what I am hearing (equalized comparisons to determine the exact level difference at a certain point) and measuring, the slight boost isn’t more than 3 dB at 100 Hz, 4 dB at 50 Hz and a bit less than 5 dB at 30 Hz and below compared to the ER•4SR, which is not much but enough to give the ER•4XR a bit more sub-bass and midbass quantity along with a little more warmth in the lower root without affecting the midrange balance. Speaking of the midrange: both my ears and my measurements as well as those on the included certificates tell me that the ER•4XR has got a little less of a presence range lift compared to the ER•4SR wherefore it will be perceived as being a little less fatiguing over time. It has also got slightly more level than the ER•4SR I have on hand around 10 kHz and between 10 and 20 kHz, wherefore it is a little brighter than the ER•4SR to my ears but not to the extent of where we could really speak about an emphasis (there might also be some small production tolerance in place), as the difference is quite small actually and both mainly differ in the bass.
Both in-ears sound equal to me when it comes to detail retrieval and bass quality.
The ER•4XR has got an almost identical soundstage to my ears that is just ever so slightly less deep and the minimally less precise separation.

Shure SE425:
The Shure is somewhat more on the mid-centric side of neutrality.
The SE425 is comparable to the ER•4SR in the bass department but has got slightly more upper bass and lower root. To my ears, the Shure’s midrange is somewhat more emphasised. The SE425 has got somewhat less level in the highs, however just slightly. Though, it starts rolling off audibly earlier wherefore treble extension is limited on the Shure – the Ety has got the better treble extension above 10 kHz.
The ER•4SR is the in-ear with the higher detail retrieval and better transient response out of the two in-ears.
The Shure’s soundstage is quite small and congested in comparison, and the Ety also features the better instrument separation.


Conclusion:

The king is dead, long live the king!
 

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The Etymotic ER•4SR is a worthy successor of the legendary ER•4S with a most widely similar sound signature with just minor tweaks on the sound side and a better cable as well as a better ear tip material.
If you already own an ER•4S, I don’t see the absolute necessity to get the ER•4SR, as while there are some differences on the sound side, they are anything but major. However if you don’t already own a measurably really flat in-ear but need or want one, the ER•4SR should be your model of choice as it has got what is probably still the flattest and most uncoloured sound ever found in an in-ear, based on research that still remains true.

I have always considered the ER•4S as a reference and legend since the first day I had it (correctly) in my ears, and the same goes for its successor.
The only thing that I could wish for are coloured side-markers on the cable connectors, however given that the old ER•4 line also underwent some cosmetic changes over the years, I wouldn’t be too surprised to see the ER•4SR and ER•4XR with colour-coded side-markers in the future as well.

First of all, thanks 

to 

hifiheadphones

 for the review tour invite.
 

Secondly and mainly because I believe the ER4SR & XR are worthy of the praise he

showers upon them

, I feel duty bound to refer you to the reviews of mark2410. Finally, because these are my first reviews (& I'm devoid of creativity), I'm also going to crib from his review structure (thanks mark2410, I hope you don't mind)?! 
 
Before I move on, I must admit I'm not fluent in 'audiophilese' and my experience of quality IEMs isn't particularly extensive or recent! My current set up up at home is mainly Tidal HiFi (via Mac), Chord Mojo & AQ Nighthawks (which I love!). Out and about I tend to stick to a pair of wireless Momentums (and I do have a pair of rarely used In Ear Momentums). 
 
I have, in the very dim & distant past, owned a pair of Shure SE 5..'s (530's I think - the 'Push to Talk' ones?), and whilst I thought they were good, I don't remember thinking I'd be happy with them as my main/only headphones. I've also had previous Etymotics - the HF3 & 5 when I first began experimenting with how I might get better performance from iPods & early iPhones. My abiding memory of them is of the pleasing levels of detail & clarity they used to reveal. More on that to come.....       
      
Anyway, on to these Etymotics:

 

Price:  £330. I must admit, I have a bit of a mental block, based purely on their physical size, when it come's to paying as much for IEMs as I might for on/over ears. Daft, I know! Looking at what's out there in terms of the market though, I can only assume it must be diminishing returns over & above what these little beauties offer.  

 

Specifications:  

Frequency Response 20 Hz-16 kHz, Accuracy Score 4SR (92%), Transducers High performance balanced armature micro-drivers, Noise Isolation 35-42 dB, Impedance (@1 kHz) 4XR (45 Ohms), Sensitivity (@1 kHz), SPL at 0.1V 4XR (98 dB), Maximum Output (SPL)       122 dB, Cable 5 ft. Detachable, Warranty 2 years

 

Accessories:  Standard assortment of silicone tips and a big old case! As someone who tends to bundle IEMS up into a coat pocket, I'd probably only keep the case in my work bag & use it when travelling. For that, I think it's pretty handy. For daily use; yeah, it's not something you're going to fit in a pocket! 

 

Build Quality:  It's simple structure, extremely well made. My only gripe was the only easy way (out of the box), to determine which unit was left or right was by the orientation of the logo on the housing (the cable plugs are embossed but the text is small & difficult to pick out. Overall, the build has a premium look & feel.

 

Isolation:  Regardless of tips, you'll struggle to find much (that I'm aware of), that will passively isolate to the same level as the Etys. 

 

Microphonics:  No getting around this one, this one takes a bit of management. You can wear them up but as they're not strictly designed for it, they do stick out a little. The chin slider and shirt clip do help a lot though. Furthermore, and it's a nice touch, the clip easily attaches to the cable bridge/Y junction. Nothing noteworthy on the surface but on the couple of occasions I did snag the cable, rather than the first point of resistance being my ears (if you're wearing the flanged tips - this hurts!), the cable just disconnects from the clip alerting you to a problem.  

 

Comfort/Fit:  I can only speak from personal experience but I get on best with the bigger, triple flanged tips. There's no way to make the procedure I've adopted for fitment look attractive. It involves pulling up on the earlobe whilst opening my jaw & inserting the tip to the point a vacuum's created and it feels like your ear is trying to suck the thing in!! Disconcerting at first but my favourite tips in achieving the best seal & sound. I think your ears do toughen up &/or the tips soften with only a little use. I've tried the other tips & Complys in the past but stand by these. Complys I like but part of the attraction of an IEM for me is being able to quickly insert & remove them which I always find slightly fidly with Complys  

 

Aesthetics:  They look premium but are pretty much swallowed in their entirety by your ears anyway!

 

Sound: I'll admit, my (mis?)memories of the HF5 had me expecting something very detailed but potentially bright & fatiguing. I needn't have worried; these provide an insight and detail retrieval I've never encountered in any headphone before. It's not achieved by boosted treble or tricksy tuning either; it's actual real life, genuine detail - and it's addictive!! It's cliche but I enjoyed re-listening to tracks not necessarily to discover hidden depths or detail (which they do provide, in spades), but just because of the sense of reality they provide. Instruments (in particular electric acoustic guitars), actually sound life like; as if you were stood close enough to pick out granularity in tone and texture of the instruments. Separation is excellent and I also found the soundstage and depth that these present convincing too.

 

As the 'Studio Reference' badge indicates, these are a serious effort at providing the user with the means of being able to easily pick apart a track. As such, it's safe to say that they could be perceived as being a little overly clinical. They handle bass well both, technically, in terms of quantity & quality but not in an overly pronounced and impactful manner. As a former bass player, I must admit, to a preference for the XR's. They're identical in every way to these but with just a little (I mean a little), more grunt over the lower frequencies.      

 

These sound good straight out of my iPhone 6S Plus (& I could live with them as is), but throw the Mojo into the equation and they do what they do well but even better! MacBook, Mojo and a couple of AQ Jitterbugs nudge a little more performance out of them too. Amping certainly helps bring a little more to the lower frequencies and just 'peps' them up all round! 

 

Value:  For me; the biggest compliment I can pay these is that I'd be happy with them as my only pair of headphones. They've awoken in me a realisation of what IEMs are capable of to the extent I'm seriously considering downsizing to an IEM only inventory!

 

Pro’s:  Stunning levels of real detail, clarity & separation.  

 

Con’s:  None to speak of but what these are designed for and deliver on (& then some), might be perceived by some as lacking an element of 'fun'. Those same people may potentially find them a little bass light too (even the XR's).