Sennheiser IE60 In Ear Headphones (Earbuds)

Sennheiser is a very well known name in the headphone game. My first good headphones, and the center of my first high end audio system, were the Sennheiser HD580s I had in college. The company has always been known for high quality over the ear, open back headphones. This type of design can deliver fantastic sound quality, but at the price of large size and pretty much zero ambient noise isolation. In ear headphones have been part of the Sennheiser line for a while, first with their professional line of wireless monitors, and then with the IE6 and IE8 consumer headphones. The latest IE60 and IE80 models are Sennheiser’s current entry into the market of small, high noise isolation headphones pioneered by Etymotic with their seminal ER-4S. I owned a pair of ER-4Ss for 10 years, using them for travel. The high noise isolation combined with great sonics completely embarrass many a costly noise cancelling headphone. I recently replaced my ER-4Ss with a pair of Shure SE425s, which use multiple balanced armature drivers as opposed to the single dynamic driver in the Etymotic. How do the Sennheiser IE60s stack up to these two classic in-ear headphones?

The IE60 is a very compact headphone, barely larger than a cheap earbud. They can be worn like a normal earbud, or used with detachable earhooks that guide the cables above the ear a ‘la Shure. The headphones come with 6 sets of eartips: single or dual flange, each in three sizes. The result is a very comfortable headphone that can be customized to the user’s preference. The only drawback was that no triple flange eartips were provided. This eartip provides the best isolation, and is the type I prefer to use, although many people find them uncomfortable. A detachable clip is provided to secure the cord to your shirt. The headphones come with a very sturdy hardshell case that protects the headphones, extra eartips and the provided cleaning tool very well. The only drawback of this case is that the headphones have to be carefully put away every time to get the case to close. I found on a recent trip to Europe that it was quite a pain to get the case closed when in a hurry leaving the airplane. A little extra space would have been welcome.

The Sennheiser IE60 (one step down from the top of the line IE80), priced at $249.95 follows the Etymotic prescription of a single dynamic driver, but promises to bring powerful bass to the party. One of the main limitations of the Etymotic ER-4S was in the bass. The single driver design produced incredibly fast, sharp midrange and treble, but at the expense of lightweight bass. The dual balanced armature drivers in the SE425s fix this problem, but then require careful design to maintain razor sharp focus. The IE60 tries to deliver bass surpassing that of the SE425s, while maintaining the speed advantage of a single dynamic driver.

Bass is something this headphone has in spades. In fact, I’m sure many users may conclude that the IE60 has too much bass. It’s tonal character leans toward the bass powerful Denon AH-D7000. Compared to the much more expensive and large Denons, the IE60’s bass is a bit wooly, but still offers plenty of power and agility. If you want powerful bass from an in ear headphone, the IE60 should definitely be on your audition list. It offered WAY more bass than the ER-4S, and a bit more than the SE425. For me, the bass was a little overwhelming at times on certain recordings. I preferred the tonal balance of the SE425, but that is definitely a subjective opinion.

The IE60 offered a very large and expansive soundstage, larger than the SE425. The detail and speed were also excellent, landing somewhere between the Shure and the old standby Etymotics. The high end of the IE60 was more rolled off than the Etymotics, but this could be welcome for most listeners who find the Etymotics quite bright.

With any in-ear headphone, obtaining proper fit is essential to sound quality. If the eartips do not form an air-tight seal with the ear canal, performance will suffer (particularly in the bass). I found it a challenge to get the IE60s to fit my ear. I had to use the smallest two flange eartips, and still found it a struggle to get them to consistently fit right. I greatly preferred the 3 flange conical eartips included with both the SE425 and ER-4S. Again, this is a personal issue. Your experience may be different depending on your fit preferences.

I measured the IE60s using my M-Audio Profire 610 Firewire audio interface with Spectra Plus FFT software. I used an Earthworks M30BX microphone coupled to the earphones with a short length of surgical tubing. The microphone’s absolute calibration was set using my normal stereo and a Radio Shack SPL meter to 100 dB at 1 kHz. The headphones were powered directly by an analog output of the 610, set in amplitude to provide a 100 dB SPL tone at 1 kHz. THD was measured at 20 Hz and 1 kHz, IMD was measured using a 60 Hz + 7 kHz tone, and frequency response was measured with white noise.

Distortion was measured at a very low 0.6% at 20 Hz and 0.02% at 1 kHz. The 20 Hz number is likely an upper limit because of the configuration of the FFT software used to maintain compatibility with the rest of the headphone tests in this shootout. THD+N levels were much higher because of low frequency pickup from the environment, and should not be trusted. IMD was measured at 0.01% (essentially zero). Frequency response is flat from 200 Hz to below 20 Hz, with a broad and shallow dip from 200 Hz to 3 kHz. At high frequencies, the response rolls off, with a couple of peaks at 7.5 and 15 kHz. These peaks are likely from standing waves in the test apparatus (the cavity created by the surgical tubing, microphone and headphone). Most headphones have a strong roll-off at high frequencies. Because headphones (particularly in-ear headphones) fire sound directly into your ear canal bypassing all the ridges and folds of your ears and propagation around your hear, the optimal measured frequency response is NOT flat. A headphone that measures flat in the way we tested would sound horrifyingly bright. The job of the headphone designer is to craft the frequency response of the treble to sound flat. In this sense, it is very difficult to interpret the high frequency end of headphone frequency response graphs. For any frequency above about 5 kHz (where the wavelength of sound is comparable to the size of your ear), you can forget about getting anything meaningful from the response graph. For frequencies below this point, the results will be trustworthy.

I enjoyed my time with the Sennheiser IE60s. While I still prefer my Shure SE425s, the IE60s have some very nice qualities, including a very competitive price. If you’re looking for a compact and lightweight in-ear headphone with strong bass and want to spend less than $300, the IE60s should definitely be on your short list.