Throughout my time in audio, I have built countless fond memories of music discovery with Etymotic IEMs. In fact, the ER4P-T was of the first earphones to impress me through its resolution, speed, and somewhat unorthodox midrange-centric tonality. Despite having subsequently experienced others, I affectionately remember its peculiar fit (and sound) to this day.

Although the market has since evolved significantly, with mid-fi becoming exceedingly competitive, the legendary single BA has demonstrated top tier staying power despite being a 30 year-old design, a recurring theme with its manufacturer. Since my ownership of the ER4P-T, I have owned an MC5, ER2XR, ER4B, and ER4SR/XR – all of which delivered excellent performance relative to competition. So, when noticing Etymotic running a naming contest, I had to share my idea. After all, a free pair was up for grabs.

Well, turns out they’ve listened, and with some adjustment, settled on the name EVO. This brings us here. I would first like to express gratitude towards Ety for making this opportunity possible and am glad to have contributed towards this important release’s name.

A brief history lesson
In celebration of the brand’s long history, I dove into my IEM drawer, to withdraw what I perceive to be the two “extremes” of the 30-year-long Etymotic story, building the ramifications of this comparison.

On one end of the spectrum lies the ER4B (Binaural): it represents the single BA ER4’s original tuning from 1991, faithfully adhering to the Diffuse Field target. At the time, many users found it ruthlessly bright, leading to its supplementation by the slightly more docile ER4S (Stereo). Both IEMs’ cables contained resistors in series, increasing impedance and making them to be somewhat difficult to drive by the increasingly popular portable sources. As such, Etymotic once again conceded by removing them, leading to the advent of the even darker ER4P (Portable), and later ER4P-T (Portable Travel, an ER4P with a resistor adapter turning it into an ER4S on the fly).
Etymotic later refreshed the ER4 through the SR (Studio Reference) and XR (Extended Response) models in 2016, replacing the 2-pin plastic earpieces with modernized proprietary MMCX plugs, and imparting minor modifications to the drivers. Whilst I personally found them to sound a bit rougher and grainier than the originals, they quickly became massively popular. The SR was tuned towards the ER4S target, with the XR’s vented full-range BA delivering a trendy sub-bass boost. The ER3 then came, using a similar design with looser quality control, at a fraction of the price.
Throughout the years, some users complained of the ER4’s textural dryness, leading to implementation of a dynamic driver model. Indeed, the ER2XR represents to opposite end of the spectrum. It is the warmest, thickest and richest-sounding Etymotic to date, with a very attractive price tag (sometimes $50 on sale!) contributing to its wild success.

Enough with that now – let’s talk about the EVO.
Design & Ergonomics
This is Etymotic’s first-ever multi-driver earphone. It boasts a 3 BA setup: 2 low, 1 mid/high, with a 2-way crossover. Impedance comes in at 47 ohms, with a sensitivity of 99 dBSPL at 0.1V. Whilst multi-BA IEMs are typically very easy to drive, this is on the power-hungry side. I have primarily used the Bryston BDA-1 DAC and BHA-1 amplifier for this review, but that is certainly overkill: you’ll still have no problem driving this from most phones, DAPs and dongles.
The stainless-steel injection molded earpieces are beautiful, robust and confidence inspiring. Given the nozzle length and angle, these replaceable filter earphones, similarly to the ER2/3/4, provide deep insertion depth, albeit to a slightly lesser degree. While fit remains slightly unusual, it is less intrusive thanks to the shell’s close contouring by the concha and the cable looping around the ear, allowing for more uniform weight distribution. Nevertheless, I do find myself missing the classic Ety low profile form factor, especially considering that the isolation, whilst still terrific, isn’t quite as effective as the ER4’s.

The single-ended 3.5 mm detachable Linum BaX silver-plated copper cable is supple, but extremely thin past the Y-split. This comfort benefit may introduce possible durability concerns for intensive users. The T2 earpiece connectors, however, boast supposed reliability benefits over MMCX and 2-pin solutions at the cost of a limited aftermarket.

Accessories are run-of-the-mill for a $500 IEM – the usual included with an Etymotic, except for the familiar zippered pouch being substituted for an internally padded aluminum “jar”: more protective, but less compact and hence cumbersome for on-the-go usage.

Sound
I enjoy the EVO and find it to be an interesting change from the ER4. Sound signature exhibits a minor sub-bass shelf, into an ever-so-slightly warm midrange, freshened by some extra low-mid treble energy, followed by a rolled off upper treble region. It exhibits some interesting technical quirks. In some ways, it represents a midway point between the leaner, brighter and drier ER4B, and the “full-fat” ER2XR.
Bass
Bass extension is, like in most IEMs, without reproach, supplemented by a significant sub shelf with little intrusion into mid-bass. Slam is also excellent for a pure BA IEM (comparable to something like an IER-M7/M9), though it still lacks the extra richness in texture and immediacy of attack of a good dynamic driver (e.g. EX1000, which sounds more impactful despite the absence bass boost). Decay also likens itself to a DD, although attentive listening reveals the lack of reverb characteristic to balanced armatures. Nevertheless, a solid effort: this certainly avoids the typical traps of BA bass, which sounds one-notey and wooly on exertion, and dynamically flat – all terms that can accurately describe the leaner ER4’s bass.
On the other hand, some may expect the ER2XR’s dynamic driver to emerge victorious from this battle, but this would be expectation bias. Sure, its decay lingers longer, adding weight and richness to lower registers, but the more conservative sub-bass boost delivers softer attack, and the compressed dynamics detract heavily from its raw impact.

Midrange
The EVO’s midrange is tastefully tuned towards the warmer side of neutral. I am uncertain of the deep insertion’s role in this perception, but it is tonally richer than what is shown in FR graphs. This is a strong shift in character in comparison to the ER4, as the EVO is a significantly thicker-sounding IEM. Note sustain is more persistent (though again, less than most DDs), and upper midrange sounds less grainy and rough despite maintaining a slight amount of “BA grit” in vocals and brass. This isn’t the mere smoothness, or lack of texture that affects many full-BA IEMs such as the CA Andromeda – there’s a sense of bite, adding character to the EVO. This “etch” affects perceived resolution, but there certainly is some to spare here: this remains the most resolving midrange in any Etymotic product thus far, despite the ER4B’s aggressive 2-4 kHz region somewhat artificially pushing artifacts forward.
Now, this isn’t to say that the midrange is entirely ruthless in character. While microdynamics are considerably improved, leading edge is less incisive than the ER4’s, with the initial piano strikes and string plugs carrying more heft than your run-of-the-mill BA. That mellows things down, but it certainly doesn’t lean as much into the syrupy territory of the ER2XR, which is by far the richest and smoothest of the bunch – most natural, but also haziest.

Treble
Treble is where complications arise for the EVO. A slight low to mid treble elevation can be heard, followed by a rolled off upper treble region. The EVO demonstrates freshness and “tang” through this elevation, but suffers from a clear lack of cymbal sparkle and air. This, along with the sparse presence of etch, is reminiscent of older BA monitors such as the UERM, displaying it at the cost of refinement. This is far from EX1000 levels of roughness, though when comparing it to more ethereal and resolving BA tweeters such as those of the U12t, the EVO completely falls apart. Also, while it extracts more information than the comparatively veiled ER2XR, I must admit being miffed when comparing it to the ER4B, which not only extended further, but sounded smoother and less splashy despite being brighter.

Verdict
You may have noticed a pattern emerging throughout this writeup. In terms of FR tuning and texture, the EVO represents a middle point between the “extremes” of the Etymotic experience whilst presenting more nuance than anything previously released by the manufacturer: it offers greater dynamic contrast and resolution (barring treble), improves on the ER series’ two-dimensional image, (albeit very minimally, likely because of the similar nozzle and insertion mechanism) and pulls more microdetail out of recordings than either of its predecessors (despite the ER4B’s elevated top end pushing macrodetail forward). There is no doubt that it is a more polished and refined product than its ancestry, both in technical proficiency and build quality, and is a very good IEM for $500. However, as a successor to the legendary ER4, it enters the market with crucial implications.

Regrettably, as a long time Etymotic fan, I fail to perceive in the EVO the “instant classic” status of its predecessor for reasons revolving around safety. Yes, the midrange assumes some risk with the tasteful inclusion of textural coarseness, though I can’t help but feel that the ER4’s unorthodox form factor, unbeatable isolation and sonic ruthlessness yield a stronger sense of identity that, albeit controversial, parents a more loyal and affectionate following. This is especially magnified given the current state of the IEM market, where standing out is tougher than ever: ~$500 concha-fit releases following a similarly warm FR target are multiplying, and the space remains ridden with fierce performers. Whilst this evolution will faithfully serve an elegant achievement that will carry the ER4’s torch, it remains a product of its time…
… an era where the burden of notoriety is heavier than ever.
