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A Revolutionary IEM with Unparalleled Sound Quality

A Review On: Audeze iSine 20

Audeze iSine 20

Rated # 201 in In-Ear
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Review Details:
Audio Quality
Posted · 7650 Views · 13 Comments

Pros: Class-leading sound stage, imaging, clarity. Light and comfortable.

Cons: Plastic housing, poor sound isolation. A radical design that may not be for everyone.

When a buddy of mine who is in the inner circle of Audeze asked me if I wanted to try the new iSINE 20, I was thrilled. Has Audeze, a company known for large and heavy full-size headphones , done the impossible and shrunken the planar magnetic sound into a small IEM package. As a former owner of the LCD-3 and current owner of the LCD-XC, I also want to know how the iSINE compares to its larger siblings. Lets move on!




In-ear, universal fit

Transducer type

Planar magnetic, semi-open

Magnetic structure


Magnet type

High-grade neodymium

Diaphragm type

Ultra-thin Uniforce

Transducer size


Maximum power handling


Maximum SPL


Frequency response

10Hz – 50kHz


<0.1% @ 100dB


24 ohms

Cable type



20g without cable

Inner Nozzle Diameter                                          6.35mm      


Looks, Comfort and Build Quality



There is nothing subtle about the design and appearance of the iSINE. If you had to imagine what an offspring would look like, if a bee hive and Star Wars Tie Fighter had a sexual indiscretion, the iSINE wouldn’t be too far off. The large hexagon frame of the iSINE immediately grabs your attention. Through its lateral fenestrations, the gold-tinged grills create a nice contrast with the darker housing. The iSINE is one of the largest IEMs I have seen. It doesn’t sit in your concha bowl like most IEMs. The only way to stabilize it is by wearing it with the over-the-ear ear guides (1 black and 1 clear both same size) or ear locks that sit in the concha bowl (2 sizes both black). That being said, the iSINE is still fairly comfortable because it’s only 20g, and the ear guides really helped keeping it firm and tight on my ears. I didn’t really like the ear locks.


iSINE 20 with Tie Fighter

The Tie Fighter is a father now or mother?


iSINE 20 compared to ES60

iSINE 20 vs Westone ES60


iSINE 20 compared to IE80

iSINE 20 vs IE80


The long, tentacle like sound tube measures ¼ inch in diameter. You get 3 sizes of tips to use. I have very small ear canals, and I cannot fully insert the smallest tip into my ear canal for optimal seal. At this point, I’m not aware of any 3rd party tips that are large enough to be used with the iSINE. Only rubber/silicon based tips are included, so there are no foam options. This may be an issue for some users with narrow ear canals.


iSINE 20 accessories.

Included accessories


If you expect hand carve wood and all metal design, you will be disappointed by the iSINE. Its housing is constructed with almost entirely out of plastic. The cable insert actually started to crack a little when I accidentally inserted it in the wrong orientation. I wish Audeze could use metal for the external housing.


iSINE 20 sound tube

iSINE 20 has a very wide sound tube


iSINE 20 how it sits in the ear

iSINE 20 is very comfortable in the ear


iSINE 20 cable insert

iSINE 20 cable insert


iSINE 20 2-pin cable.

iSINE 20 2-pin cable


You can pay $549 and get the iSINE with standard 1/8” cable or pay another $50 to get both the lightning cable and the standard cable. The iSINE accepts 2-pin. The standard cable I have is flat, flexible and tangle-free with minimal microphonics. When you insert the 2-pin, make sure you line up the right orientation with “L” and “R” on the outside.


Sound Quality



Personally, I favor planar, full-sized headphones over dynamic headphones. I feel the technology is superior.  The planar driver technology differs from dynamic headphones in which the charge is spread across the magnets. So instead of focusing the force on a small portion, it’s spread more evenly across the diaphragm. This design results in very low-distortion sound and faster response. This is how planars get those tight bass. Read more at http://www.trustedreviews.com/opinions/dynamic-vs-planar-magnetic-drivers#kGc5k3H4dB8quKaL.99

Similar comparisons can be made between balanced armature vs dynamic IEMs. In a balanced armature (BA) design, the drivers to not displace air in order to generate sound, so typical BA IEMs have better sound isolation. I definitely hear that difference between the IE80 vs ES60. Also multiple drivers allow more flexible sound tuning. This how you get that better treble performance, faster response and more detailed sound. However, it's much more costly to produce similar to planars.


Before you call me a fanboy. I do believe that a well-implemented set of dynamic headphones can sound better than any given set of planars. I really liked the Fostex TH900. I didn't keep it before personal preference in sound signature.


So you ask why not make planar IEMs and have the best of both worlds. Fast and accurate response without the cost of a 10 driver BA. That's because planars requires larger magnets in greater quantities than a dynamic driver headphone. This is why most planars are large and heavy. To squeeze such technology into a small form factor is extremely challenging task. Well, Audeze has done just that. But does it reality sound as good as theory? 


Imaging, Sound Stage, and Instrument separation



To my ears, imaging, sound stage and instrument separation are otherworldly. In well recorded tracks, such as Amy Winehouse’s Love is a Losing Game, the iSINE effortlessly portrays the position of individual instruments. Compared to previous IEMs I have had, Sony XBA-Z5, Sennheiser IE80, and Westone ES60, the iSINE’s sound stage is astonishing. You feel like you are in a large concert hall. When I switch back and forth between the ES60 and the iSINE, the ES60 sounds very congested while it still has excellent clarity and imagin. There is a pleasant sense of freedom when you start to listen to iSINE for the first time. I don’t think this can be achieved by any dynamic, balanced armature, or hybrid IEMs. The planar and open design of the iSINE is light years ahead in this department, and this may be the primary reason many consumers chose to buy the iSINE. 


Clarity and Transparency


This is another strength of the iSine. It sounds transparent and clear across the whole spectrum.




If you want to be judgmental, you can describe the upper range in the iSINE as recessed or subdued. If you want to be political correct, smooth may be a better adjective to use. When compared to my ES60 and Hifiman Edition X, the iSINE doesn’t carry the crispness, sparkle, definition and extension. This may be an issue for some buyers. 




As with most Audeze products, it has amazing bass. The sub-bass quantity and the mid-bass punch are both excellent. Overall bass is balanced, tight, and controlled. It’s just thick enough to present the details without appear lean but does not overpower rest of the track.




The mids also stands out for me. There is a very rich tonal balance with no loss of detail. The sound is organic and lush. Both female and male vocals come alive with the iSINE.


Sound signature


The iSINE carries an overall warm sound signature. This follows the general trend of Audeze house sound. You definitely can’t call it “reference quality.” Personally, I feel one of the benefits of the warm sound signature is that it’s less fatiguing and more enjoyable over long listening sessions.


Sound isolation


There is audible sound leak. You can hear it if you turn the volume all the way up or if you are in a quiet environment. You are not going to bother anyone at Starbucks or on a public transportation, but you probably will be turning the volume higher than you want due to poor isolation. I will not be taking the iSINE 20 out on a BART or Muni right. I will be reaching for the ES60 every time. 





The iSINE is a revolutionary product. Audeze was able to package planar magnetic technology into a small and attractive package thus creating a new product category, planar magnetic IEM (PMIEM or maybe ortho IEM (OIEM)). The iSINE is light and comfortable. If you can accept the radical and dramatic design, you will appreciate the full-sized headphone like soundstage, imaging and clarity. The only complaint is that I wish Audeze used all metal housing. With all the appraise, iSINE also rests in an unusual territory. If you are getting an IEM for daily commute or listen in a crowded environment, the iSINE is not going to isolate sound like a traditional IEM or custom IEM. I would never pick the iSINE over the ES60 if I’m riding the Muni in San Francisco. If I’m at home, I would probably prefer reaching for the full-size Hifiman Edition X or LCD-XC when I’m sleeping next to my wife and kids. So when would I wear the iSINE if I owned one?  You need to think about where the iSINE will position itself in your listening lifestyle. Nevertheless, I believe the iSINE is going to sell well. It has a great price point where it’s relatively affordable for most in today’s standards. It’s a monumental product as the first planar IEM.


Definitely not for me. But it's a cool idea.
It seem just match what I expected, can't wait to have isine :)
Thank you very much for the review!
Readers, something to take note of here: The lack of the Cypher DAC/AMP in this review is significant. People who listen to this IEM with the Cyper cable at its default "house" settings may have a completely different listening experience.
Those plastic shells - what were they thinking?? I hope their returns department are getting plenty of sleep right now.
As you have mentioned in your summary  - the biggest issue I've got - what is the use case of this product? When a person should buy it?
For commuting? No.
For home listening? No.
For open office listening? No.
Why would one buy that? I can appreciate how great these sounds, but I don't understand their use case...
Good read.  It answers all of my questions about the Isine thoroughly and clearly.  I do not understand the use case or why they would make an open back iem like this?  I am sure I would love the sound, but the isolation and sound leakage are kill it for me.  If it was closed and isolated it would be a no brainer.  This product for me right now is a head scratcher.  I want to buy one, but know the isolation will cause me more frustration and they would just sit in a drawer after I try them.  Too bad.  This had potential to be epic.
I will likely be picking up a pair.
I use my Ether C at work, however I want a pair of headphones for around the house.  With a young child in the house and a wife that works late, it would be great to have a pair of high quality sounding, "portable" headphones I can wear, but still be somewhat aware of noises around the house.
Perfect for my unique usage case where large headphones are simply cumbersome and most IEMs block out the world.
I am currently using my old Koss PortaPro to fill this role.
Interesting product, the sets just arrived in Singapore and I happen to see this review... as with all new techs from Audeze, reliability might be an issue and plastic... magnesium carbon would have been a better choice... but then I am not an expert...
Thanks for your review!  I was intrigued by this sentence:
"You can pay $549 and get the iSINE with standard 1/8” cable or pay another $50 to get both the lightning cable and the standard cable."
I hope this is true, but so far I haven't seen the iSINE 20 offered with anything but both cables for $599 (checked Headphone.com, Moon Audio, and even Audeze's Private Lounge).  Being fully in the Android camp, I have no need for any purposely proprietary iPhone connectors.
My pair arrives next week with cipher cable. In experience the cipher cable makes Audeze products sound better over 3.5mm. I compared the Sine with cipher to xlr and was blown away. Cipher cable sounded better even when EQ was set the same on both systems. I am probably going to sell my DAP and other iems. Now that Shure is making a lightning cable for its iems, there is no need.
BAs still move air, they work like billows starting a fire. But regardless, great write up. You had me at the picture of a tie-fighter and the iSines. Love your blend of top notch info and humor.
Is it possible that any IEM can better the exquisite vocal reproduction of the Sony XBA-Z5? I certainly don't believe so.
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