Etymotic Research ER4SR review

Flat as a pancake: Etymotic’s ER4SR offer classically clean sound in a more resilient package

Etymotic's new ER4SR headphones get a stronger build, and keep the squeaky-clean sound.
Etymotic's new ER4SR headphones get a stronger build, and keep the squeaky-clean sound.
Etymotic's new ER4SR headphones get a stronger build, and keep the squeaky-clean sound.

Highs

  • Vividly clear mids and highs
  • Dynamic and revealing sound stage
  • Excellent passive noise isolation
  • Great variety of accessories and tip choices for optimum performance
  • Solid build quality

Lows

  • Bass feels restrained on heavier-hitting tracks
  • Can be hard to get a good seal with certain tips

DT Editors' Rating

There’s a lot of history behind each line of Etymotic’s in ear headphones, but especially that of their latest ER4XR and ER4SR models. The company’s ER-4 “Canalphone” marked the first ever high-fidelity in-ear monitors available in the consumer market when they launched in 1991 and, through various performance-based updates, the headphones have remained beloved in the audiophile community ever since.

For its latest iteration of the classic in-ear model, Etymotic has equipped two aesthetically identical headphones with two slightly different sets of drivers, giving the Extended Response (XR) a boosted low end, while retaining its classic “flat” profile for the Studio Reference (SR) model. Since both models are essentially carbon copies until you get to the actual sound signature, we’ve cut one review into two, with the only difference coming at the all-important performance section.

Despite their shared looks, plentiful accessories, and excellent build quality, we can’t help but prefer the one with the extra bass — especially since it retains the same level of high-end clarity that we know and love from the brand. Follow us below to see why, or if you prefer a smooth helping of sumptuous bass, click here for the ER4XR review.

Out of the box

Both sets of headphones in the new ER4 line come identically packaged, save for a slight color difference on the digital soundwave which appears on the exterior of the black box; The XR gets a lime green soundwave, where the SR gets one in what we like to call Digital Trends blue. Once an exterior sleeve is slipped off, the headphones pull out of a classy black box inside, where they are tastefully displayed peering out of their included hard case.

The hard case sits, mostly hidden, below a white envelope which congratulates one on the purchase, along with a thorough performance certificate — a nice touch for $350 earphones, which should alleviate concerns of any defects, further buoyed by Etymotic’s stellar track record.

The case is a fairly hard neoprene shell with a raised Etymotic logo which unzips to reveal multiple pockets. The headphones store safely in the back divider of the right side, with zippered pockets that contain two pairs of the three different ear tip options (two triple-flanged in different sizes, one foam), a cable clip, quarter-inch adapter, and four replacement filters with a replacement tool. That’s a lot of goodies; Suffice it to say that this package has just about everything you could possibly need.

Features and design

As mentioned, the look of the new ER4 series is identical regardless of which model you are looking at, and should be familiar to those who’ve seen any vintage model in the ER4 line. The in-ears are thin black tubes with durable wound cables, leading to a sturdy cable divider and a long rubberized cable the culminates in a gold-plated 3.5mm jack.

Feed the ER4 top quality recordings and you’ll love the depth and complexity they deliver.

The company has added an MMCX connector to each earphone, meaning that the cable can be replaced if it undergoes extra wear and tear. An especially nice touch is a fitted slot that keeps the MMCX connection from rotating (a common gripe with other MMCX connections) which Etymotic calls a “keyhole.” The body of the earphones has been upgraded to machined aluminum, in hopes of making broken earphone stems a thing of the past. They feel hard and sturdy, but still extremely lightweight.

The three sets of ear tips offer many size and fit options. As usual, the two sets of triple-flanged ear tips (one big, one small) offer the flattest sound response, with the foam tips providing the best sound isolation and long-term comfort. Despite slightly boosted bass and cloudier upper register sound in the foam tips, the added comfort and sound isolation made them our go-to choice. We also liked their consistent seal, which some of our staff found difficult to achieve with the tri-flanged rubber.

Overall, the new ER4s aren’t any flashier than the old ones, but they aren’t meant to be. These are a subtle design upgrade to the previous model, with physical changes that should make them sound better and last longer, rather than look cooler. Given that they can be fitted with custom-molded tips for on-stage use, the ER4 models retain their heritage as a masterclass in purpose-built design. These are sleek, simple, and well-thought out all-around.

Performance

The squeaky-clean sound profile we’ve come to expect from Etymotic’s flagship in-ears remains constant on the new Studio Reference model. It’s a modernized homage to the original ER4 that is blessed with especially shimmering clarity in the high and middle registers.

The company claims it was able to eek out 6dB more sensitivity with an upgraded balanced armature driver, and that makes the SR, if anything, more clinical sounding than ever. Such accurate response can be a blessing and a curse. Amateur, digitally-produced songs that lack the warmth of big room recordings, tube amp compression, or high-end mastering will show you every pock mark, but well-made masterworks like Beck’s Morning showcase their full and dramatic soundscapes with astonishing lucidity.

Sound quality makes a huge difference to the way the SR model performs all-around. Feed the ER4SR CD-quality audio through a nice DAC, and you’ll love the depth and complexity they deliver. Feed it 128kHz Pandora streams through an old laptop, and you’ll be waiting for the sweet relief that comes with commercial interruptions.

Sonically, the only gripe we have with the flat, near-perfect curve of the SR model is a lack of bass response for modern music. It’s not that the bass isn’t there – on classics like Allen Toussaint’s Last Train we can hear every note perfectly in the mix — but it lacks a certain depth and punch. This is especially evident on albums like Kaytranada’s 99.9%, which relies heavily on sub-bass content for its buttery-smooth listening experience. The bass is there on this material, but it’s not fun, it’s not fat, and it feels like these studio reference headphones are actually mis-representing the low-end content that was present in the mixing room.

Etymotic ER4SR and ER4XR
Bill Roberson/Digital Trends
Bill Roberson/Digital Trends

That’s the problem with a studio reference headphone which, at its core, still relies on the same flat sound curve as the ER4 did 30 years ago: Times have changed. A seriously large amount of modern music is mixed with a sub-woofer, and the ER4SR just don’t replicate those frequencies as accurately as we’d like.

Warranty information

The ER4SR and ER4XR both come with two-year manufacturer warranties for defects in build and sound quality.

Our Take

For those who simply want a new version of an old headphone, the ER4SR are a quality update to the ER4 line, though their flat response does hinder them in reproduction of some modern, bass-heavy music.

What are the alternatives?

The $350 price point puts the new ER4 models at something of a middle ground in the audiophile market. Long-term competitors like Shure offer their brilliant dual-driver SE425 model for $50 cheaper, and those looking for higher-end models will want to consider both the highly durable Westone W40, or the strikingly musical Audiofly AF180.

How long will it last?

With detachable cables, upgraded aluminum stem, and replacement sets of every set of ear tips as well as filters, there is no reason to believe the Etymotics ER4SR and ER4XR headphones won’t last for many years to come.

Should you buy it (ER4SR)? No. For $350, we expect in-ear monitors to offer gorgeous, full-spectrum response regardless of input, and modern bass-heavy fare sounds lackluster on these Studio Reference models.