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Earphone Showdown: Etymotic’s ER4, Audio-Technica ATH-IM70 and LKER i1

Etymotic continues a tradition of balanced sound, but it faces stiff competition

4 min read

photo of Etymotic ER4 earphones plus accessories in the box
Photo: Etymotic Research

Even for dedicated audiophiles, the musical experience nowadays is frequently delivered by earphones. Happily, there's been an explosion in earphone ingenuity, with many models offering stunning sound reproduction and remarkable value. If you're still using the earbuds that came with your smartphone, it's time to trade up.

I recently auditioned a sample of this new earphone wave. Here I'll consider a couple of new models from Etymotic Research, a brand I've admired for years, along with a Chinese product that stunned me with its performance/price ratio. In a follow-up article, I'll consider three other surprising, audiophile-grade Chinese earphones.

Etymotic Research got its start in 1983 producing earphones for industrial, professional, medical, and scientific uses. The company had a big breakthrough in the consumer market in 1991, when it offered the ER-4S, which it claims were the first noise-isolating earphones designed to be inserted into the ear canal. The ER4 line remains Etymotic's flagship, so I was eager to check out its latest update.

Etymotic prides itself on making what it calls “reference quality" earphones—that is, earphones with a frequency response that's as flat as possible across the audio spectrum. This is in sharp contrast to almost all other earphones produced today, which either emphasize bass response (the Beats line is notorious in this regard) or have a V-shaped response that emphasizes bass and treble at the expense of midrange frequencies. Such an intentionally distorted response can make pop music, particularly hard-driving rock, hip-hop, and rap, seem more gripping and involving.

Etymotic achieves a relatively flat response in large part through the use of a single balanced-armature driver in each earphone. In a balanced armature, the sound signal's current flows through a coil surrounding an armature, producing a magnetic field to vibrate the armature. The armature is connected to a diaphragm that, as it moves, changes the volume of air in an adjacent space. This changing air volume produces pressure changes that push air out of a nozzle, resulting in a sound wave. Dynamic-driver earphones, on the other hand, are similar to conventional speakers in that they produce a sound wave by vibrating an element, typically cone shaped, which directly displaces air. The advantage of a balanced-armature driver here is its efficiency over a range of frequencies.

Both balanced-armature and dynamic-driver earphones can have just one sound-producing element (driver) per ear, in which case they are called mono drivers. Or they can use multiple elements, each covering a different range of the audio spectrum. For example, the JH Audio JH16V2 Pro earphones, at US $1,499, have an arguably ridiculous 10 balanced-armature drivers per ear.

There are two variations of the Etymotic ER4: a “Studio Reference" version and an “Extended Response" (both $349). Each has a frequency range from 20 hertz to 16 kilohertz, and the frequency response charts provided for the two different models seem identical. So, perhaps not surprisingly, I could detect no difference in performance between these two models.

I compared the Etymotic with three other earphones: the Audio-Technica ATH-IM70, which uses dual-dynamic drivers in each earphone; the LKER i1, an inexpensive, Chinese-made earphone that's also a dual dynamic; and my own Etymotic ER-4 microPro earphones, which I bought circa 2003.

The first thing to know about the ER4s is that in order to hear bass strongly with them, it's necessary to get a good fit in your ear canal. Etymotic's models are meant to go deeper into your ear canal than most other brands, and they use a triple-flange eartip to seal out external noise. The ER4s come with eartips in several different sizes; take your time to figure out which ones are right for you, or the bass will seem anemic.

photo of Etymotic ER4 earphones plus accessories in the boxEveryone Likes Extras: Etymotic ER4 earphones come with a generous assortment of accessories, including spare eartips in various sizes, a plug adapter, and a large, sturdy travel case.Photo: Etymotic Research

The ER4s really shine with small-ensemble music, such as classical chamber music, jazz, acoustic rock, vocal, and folk. I picked a few of my favorite recordings—including Lindi Ortega's “Ashes," the Beta Band's “Dry the Rain," and Chris Isaak's version of “Solitary Man"—and listened to them repeatedly with all five sets of earphones. I played FLAC (Free Lossless Audio Codec) music files stored on my Samsung smartphone through a DragonFly Red DAC (digital-to-analog converter) connected to the earphones.

With the ER4s, I was impressed with the detail in the guitars and other instruments; the firmness of the bass; and the clarity and realism of the vocals. By contrast, with the dual-dynamic driver units, the bass sounded boomier and the vocals more suppressed, and even slightly muddy sometimes, in relation to the bass.

But all that said, the current ER4s didn't sound significantly better to me than my 13-year-old ER-4 microPro. That's not really a bad thing; for 25 years Etymotic has steadfastly refused to join the boomy-bass bandwagon.

The big surprise came when I turned to the LKER i1 and compared it to the dual-driver Audio-Technica ATH-IM70. The ATH-IM70 has been my go-to earphone for several years now. It offers remarkable sound quality for its price of about $80. It emphasizes bass slightly, but not nearly as much as many others. However, after hours of listening with the LKER i1, I can report that it offers sound quality astonishingly close to that of the ATH-IM70—and for a price of about $25.

In a final round of testing, I listened to The Killers' song “Somebody Told Me" with all five earphones. It was the hardest-rocking song I could think of. On this one, the ATH-IM70s and the LKER i1s really came into their own.

The verdict: If your musical tastes run heavily to power chords, save yourself about $270 and get the ATH-IM70s. Or, even better, save yourself $325 and get the LKER i1s. Either one is going to be a lot better than the earbuds that came with your smartphone. But if you listen to a lot of small-ensemble music, take a listen to the Etymotic ER4s. You'll reacquaint yourself with midrange frequencies, and you just might find that you like them.

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