Headphone Reviews

Sound Quality with Standard Cable
I take Doc C.'s statement, "(still better than in most IEMs)," with a couple of grains of salt, but he's got a point. There are lot's of IEMs out there with blown up bass and/or uneven treble. Move up to the $600 level and things get better, but I still find many IEMs having too much fun with a "V"-shaped response. In that regard, the iSine 20 may indeed be a better listen by having a somewhat more neutral response...but it's not without flaw.

To my ears the most noticeable deviation from neutral is a fairly large chunk of the low treble significantly reduced leading to a veiled sounding response. This is exacerbated by a somewhat emphasized upper midrange that gives a moderately shouty character to female vocals.

Imaging and dynamics are just okay; to my ears the discontinuity in the low treble seems to markedly disturb these characteristics. Imaging seems to come in two layers with the bass and mids somewhat close in and the mid/high treble more distant. Dynamics tend to loose some impact and snap due to the slightly soft bass response and veiled lower treble.

Bass measures ruler flat, which to my ears leads to a mild lack of weight to the low notes, but bass is clean and tight without discontinuities transitioning to the mids. The treble quality, while reduced 2-8kHz, is very clean and articulate, and the return to level at 8kHz and above does somewhat restore balance. While tonal neutrality is number one in my book, I have to say that the low distortion and clarity of the iSine 20 does mitigate it's tonal errors somewhat.

All-in-all, the iSine 20 on the standard cable is okay, but for me, sonically not worth the price of entry. On the other hand, if you find yourself desiring the unusual utility of an open acoustic IEM, there is not other choice and the iSine is at least as good or better than many IEMs at this price.

Sound Quality with Cipher Lightning Cable
Once hooked up to an iPad or iPhone with the Cipher Lightning cable with built in DSP and correcting filters tonality gets remarkably better. Now the bass is full with proper weight; response is clean and tight delivering powerful punch and nuanced texture on demand. Bass rise starts at 100Hz and rise 5dB into the sub bass. This is similar to the Bose QC30 response and I'm beginning to believe it's a better profile than the Harman curve that starts to rise at 150Hz quickly and levels off at 4dB above for the lower half of the bass.

Transition to the mids is seamless and midrange response is on target until 500Hz where it starts to rise towards the peak at 3kHz. To my ear the rise in this area is a bit too fast resulting in a slightly forward upper midrange and presence region. I used the Audeze EQ app to lower response in this area.

I tend to like this area slightly more relaxed than most, I expect. You may want to try 1dB less attenuation than I, but I clearly preferred some attenuation in this area. Once above 4kHz I felt the iSine 20 profile was pretty spot on.

Imaging and dynamics also strongly benefitted from the tonal change. Imaging is surprisingly large for an IEM, and instruments and vocals are nicely specific and separated. With the weightier bass response and more neutral tonality, the dynamic snap and thump sounded more coherent and natural.

Like with open vs. sealed headphones, I somehow felt the iSine 20 was more coherent and spacious than traditional IEMs. I'm not sure if it's inherent to the iSine sound or it exists because you remain somewhat aware of your normal acoustic surroundings, but it was pretty apparent to me that iSines delivered a significantly better sense of space than my previous IEM experiences.

Summary
Audeze has done a really terrific job of developing this product; the iSine 20 delivered a far more mature user experience than could reasonably be expected of a first-of-its-kind product. Though heavy for an IEM, the 10oz. earpieces were surprisingly comfortable and stable when positioned with the EarHooks over my ears. Build quality, accessorization, and packaging are simply outstanding.

I felt the sound quality with the standard, passive cable was just okay. A reduced response 2-8kHz produced a somewhat veiled sound, and bass response was a tad lightweight. Switching to the Cipher Lightning cable with built-in DSP and iSine correction delivered a remarkable improvement in tonality, image spaciousness, and dynamic punch. They did sound just a tad forward to me, so I further tweaked the sound to my liking using the Audeze app to dial back just a little response 500Hz to 4kHz.

I'm definitely happy to recommend the iSine 20 with Cipher cable for iOS device owners who want a general purpose earphone that allow you to retain some situational awareness in quiet home or office environs. I really enjoyed being able to move from music to phone calls to movies in bed with ease over the course of an evening. I'll cautiously recommend it with the standard cable for non-iOS users (you can't use the Lightning cable with a Mac) who would like the open acoustic performance around the home/office. Future plug-in support for popular player software appears to be forthcoming shortly.

And yes, they'll make the Wall of Fame. Being in a class of one its either boom or bust, and for iOS fans, I think Audeze struck gold with this one. Enjoy!

Video
Click here to view on YouTube.

Resources
Audeze home page and iSine 20 product page.
Head-Fi reviews and thread.
Superbestaudiofriends.org discussion thread.