25 Years of Making a Good Thing Better: The Etymotic ER4sr and ER4XR Measurements

ER4XR Measurements
Click on graphs image to download .pdf for closer inspection.

ER4SR Measurements

Click on graphs image to download .pdf for closer inspection.

Raw frequency response plots of these earphones show they are essentially identical above about 800Hz, where they follow the neutral target well. Below 800Hz, the XR is very flat until it begins to gently roll-off around 80Hz; the XR starts a gentle rise at around 500Hz to a broad peak centered at 45Hz about 3dB higher. While I like the extra bass of the XR, the bump is too broad extending into the mids. If they had bumped up the bass more, it would excessively thicken the low mids. So while I'd like more low bass, I think Etymotic was judicious in their tuning to keep the mids in shape.

It's worth noting the distinct peaks in the upper treble. These are ear canal resonances in their natural positions and will generally not be consciously heard due to psychoacoustic masking.

The XR shows very nice shape in the 30Hz square wave. The SR gentle swayback indicates it's low frequency roll-off. For me, this just reinforces my preference for the XR. (The difference in the initial spike should be ignored as it's a result of setting the test levels with a low frequency tone. Note the 300Hz square wave initial peaks are much more similar.)

300Hz square wave are quite similar though the SR appears to be slightly less damped in the ringing after the initial peak. I think this actually might be a result of the gentle upward tilt of the remaining waveform masking the last ring, while the gentle downward tilt of the SR response acts to reveal more of the ring. Anyhow, to my eyes the peak at the initial transient seems a tad high, but the response otherwise is near ideal. This headphone should, and does, have excellent treble resolution.

The high frequency wiggles in the impulse response are due to ear canal resonance at 15kHz, and can essentially be ignored. Ideally damped would have the slight rise above zero after the undershoot go away, but that's picking nits, this is a very good, clean impulse response.

100dBspl THD+noise plots show the XR has a broader distortion peak around 1kHz and higher distortion broadly in the bass. Note the 90dBspl curves are very close to identical. I think I did perceive the XR as ever so slightly harder sounding at high levels and loud passages, but in normal listening I can't say I heard any differences clearly.

Impedance plot shows a nominally 45 Ohm headphone. This relatively low impedance coupled with the rapidly rising impedance after 5kHz will cause these headphones to brighten up with player devices that have more than 5 Ohms output impedance.

Isolation plots shows very good isolation across the spectrum. A broadband measure of isolation at -39dB is astonishingly good.

With 44mVrms needed to achieve 90dBspl at the ear, these headphone will play to solid listening levels with portable devices.

Etymotic Research, Inc.
61 Martin Lane
Elk Grove Village, IL 60007

Inks's picture

Definitely portrayed the flaws well. Still missing some bass and plenty of soundstage. I also wish it was more sensitive for portable players. i also think etymotic has to move on to dynamic drivers to improve the distortion and increase bandwidth.

On a random side note, any chance you can get your hands on the Powerbeats 3? Boy do these sound amazing which totally threw me off guard considering the PB2 were bad. So far it's my reference for imaging and soundstage on a iem and tonal balance is good, bass is cleaner than my JVC FX850s

ednaz's picture

My first IEMs were Etys, purchased from HeadRoom. I'd seen someone wearing them on a flight to Hong Kong while I was sporting my enormous (and awful sounding) Sony NRs of the long ago era. We talked a bit, he told me to go to HeadRoom, and that began a long relationship with several sets of Etys.

After a year, I got the custom tips made. (My ear canal is tall and narrow, and with stock tips, I have to choose between comfort and poor isolation, or great isolation and a wearing time of about an hour.) When I got the custom tips, what hit me even more than the comfort was the sound improvement. I recommend custom tips for them to anyone. So far, everyone who's gone to custom tips has come to the same conclusion, that they make a good IEM a REALLY good IEM. The tips from ACS go in a bit farther than the stock tips do. Despite having a few nice CIEMs, there are days when what I want is the Ety sound, and they are my go-to IEMs for using loud yard equipment, the custom silicone tips are every bit as isolating as the stock tips.

Their dynamic driver IEMs never really appealed to me, and the tips are a different size that's not compatible with my ER4 tips.

So... are the tips on these like the ER4 of the past? That would be great. I have a few sets of tips - one full concha, two the smaller type, and at the moment one set's not in use. Might be something I put on my birthday gift list...

tony's picture

That, right there, is just about the best thing anyone could say about anything. ( one hears soooooooo much sizzle now-a-days )

I went around my house looking for things that I could recommend using your phrase, I found a few easy ones, like our standard issue Maytag Laundry machines but Maytag is sort of a known given. My vast array of work tools has a standout: the little Festool CSX drill gun system ( about $300 ) is superb, far more useful than any of the Cordless guns I've owned or purchased ( during my 4 years as purchasing agent for GM ). I still own 5 Drill guns and a variable speed drill press. The little Festool is the best and most used tool I own ( I could use a 2nd. CSX and am considering buying another ).

My wife would say that her KIA Soul is a "really nice piece of gear" ( she could have any GM product ) she loves her Soul!

"Really nice piece of gear" is now my 5 Star, A+ Rating.

Thank you for the perspective.

I agree, the Etys are really nice pieces of gear ( I travel with two sets ).

Tony in Michigan

ps. I would't have known about Etys if it wasn't for IF!

Akmax57's picture

I bought a pair of the Etymotics in the mid-ninties. I think it was from Headroom. They sounded great and lasted about 15 years before one of the cables broke and I lost a channel. I remember reading they were the result of audiologists working with the hard of hearing. Only two things I didn't like - they were really not very comfortable, and the microphonics were horrible. No cable noise as long as I didn't move, but if the cable moved against my shirt, it was very noticeable. I'd have worn them a lot more if not for those two things. Still, great to see they are among the best sounding out there for what you pay.

Augustus's picture

Hey Tyll, when will we see the iSine review?

ashutoshp's picture

I own a pair of the HF5s and love them to bits. I plan to purchase the ER4s but was unsure about getting custom-fit ear molds because I worry about safety while walking, specifically, in terms of awareness of my surroundings. Is that something worth considering? Thanks.

GNagus's picture

Is it an average of the isolation at certain frequencies? Part of the reason i ask is the isolation plot for these headphones which arrives at -39dB doesn't seem so different than the plot for the Bose QC 35 at -28dB

Dan Wiggins's picture

NRR is calculated as the average attenuation at octave spacings from 125 Hz to 8 kHz, minus 2 times the standard deviation at those frequencies for a sample size of at least 10 pieces.

Basically: sum of (atten@freq - 2 * Sd @ freq)

Note that a loose tolerance (high Sd) will hurt your NRR, and that having strong attenuation at 8 kHz counts as much for attenuation at 1 kHz, even though your noise sensitivity at 1 kHz is 10+ dB stronger than at 8 kHz (meaning you can hear things that are 10 dB quieter at 1 kHz when compared to the same thing at 8 kHz).

NRR is pretty bogus as a number; you could actually build an earplug that AMPLIFIES the 1 and 2 kHz bands and still have a > 30 NRR rating. Much better to go with EN 352 and simply list the average attenuation at each of the frequency bands (125/250/500/1K/2K/4K/8K). I'm not that concerned with great isolation at 125 Hz, but at 1 kHz I'd like a solid 30+ dB of attenuation, please!

pbarach's picture

I bought a pair of Etymotics years ago from HeadRoom. None of the supplied tips were comfortable for more than 10 minutes (narrow ear canals!), and the microphonic noise from the cable made it intolerable to use these on the move. So I returned them and exchanged them for Yuin earbuds, which are perfectly adequate for walking, and I later bought some Bose Quiet Comfort phones for use on airplanes.

monetschemist's picture

I love my ER4s except that I just can't keep them in for more than about an hour or maybe two at the outside. My ears get really itchy... I think the gray (large) silicone tips are a smidgen too big and the clear (medium) ones are way too small to seal, which could be the problem. But yes, they sound great!

Mark Cherrington's picture

I've been using ER4Ps the past few years, and absolutely love them. I recognize that some people prefer more bass, but I've never felt the slightest issue there. To me, these phones sound like music, including the low frequencies. When I listen to other headphones, even very expensive, highly regarded ones, they sound overloaded with bass, and it obscures the nuances of the music. The Etymotics let every whisker of sound come through with perfect clarity, and for me that's the most important thing.

SashaRomero's picture

Dr. Mead Killion's Etymotic organization and headphone.com share an upbeat history about-facing right around 25 years. Starting with the primary audiophile in-ear earphone ever discharged,But now a day a lot more products are available in market online in cheap rate good quality like product available at https://www.linkedin.com/pulse/top-8-best-laser-christmas-lights-star-sh.... Well about the first Etymotic ER-4 show in 1991, the bleeding edge nerds here at headphone.com were among the first to perceive and offer Etymotic Research items to armies of music fans frantically looking for better solid from early cell phones like the great iPod, compact CD players and, yes, the Sony WalkMan tape machine, the top earphone wellspring of loco roller disco artists all over the place. Concocted clamor segregating, in-ear headphones. The ER Micro Pro arrangement headphones were the principal headphones popularized utilizing adjusted armature innovation and are perceived as the world pioneer accordingly precision, to which every single other headphone are thought about. After over 20 years, these reference-quality headphones are still the decision of genuine sound specialists, audiophiles and performers.

halcyon's picture

I'm an ex ER4P/ER4S user. Bought and used two pairs. The sound is an acquired taste, but it does what it does really well.

But to release in 2016 a set of IEMs for _mobile use_ with no option for an inline microphone?

Etymotic, get with the program!

Almost everybody hooks up their IEMs at least part of the time to their mobile phone. They don't want to take off deep inserting IEMs to talk or to talk to the phone. They just want to use and enjoy them.

And Etymotic has inline mics in their cheaper line.

What gives`?

So, I don't buy ER-4XR although I'd like to, because they don't have an inline mic.

2manyheadphones4me's picture

The difference in ear-tip length between the small frost and the large clear ones seem to make a difference in extension above 10kHz.
Measured with Dayton iMM-6 with PVC tube (1 inch, 8mm diameter).

large triple flange: http://imgur.com/a/LCFDg

small triple flange: http://imgur.com/a/yOKSn

Tyll, did you notice this while reviewing? If you haven't tested it, can you measure both the ear tips?

Fractal's picture

Hey Tyll, I really think you will like these earphones. I know you arent a big fan of Bose's none ANC headphones, but man, give these a shot. They might shock you :)