The only way I could describe Etymotic mc3's are a by saying that they are a different way for you to listen to your music.
The design is sleek and comes in three colors, black, blue, red and green. Enclosure of the buds is all plastic but feels to be a very rigid and durable. These are definitely very well built earbuds with a huge a amount of attention to detail included with things like user-replaceable filters that protect the moving coil drivers from ear wax. But at the same time they are very slim in profile. The cable is thin and the earbuds are smaller than average. The actual standard tips of both earbuds extrude outwards quite a bit but Etymotic have included three other very different types and sizes of tips. These are found in a bag which comes free and of course this is designed to carry your earbuds. Also to be found in the bag is a clip for attaching the earbuds into your clothing.
The mc3’s include a headset which is designed around the Apple iPad, iPhone and iPod. I used it on the iPhone and didn’t have a hiccup. Using the controls with my music, while in a call or even for Siri works flawlessly. The microphone is decent as far as audio quality goes and is plenty good for calls. But when taking a call outside with some mild wind will really disrupt the microphone leaving the recipient of the call unsure of anything your saying.
I found the standard earbud tips a fine and comfortable fit for my ears. The additional options of tips also fitted fine but the standard ones are very comfortable. If that isn’t enough for you Etymotic also offer custom fit earmold tips.
This is what it all comes down to, the sound. It’s different... I don’t mean that in a bad way though. Audio is precise, perfect and very accurate. But because of this half my iTunes library sounds awful. These lack bass, they might be able to create an awesome bass but the way they’re engineered disables them from doing so. When earbuds lack bass usually, it results in poor flat, dull audio. This isn’t the case at all. The audio is vibrant and the clarity is very impressive on tracks that are well produced. What these earbuds do is expose the music and I couldn’t believe how many tracks use bass to cover everything. 
Etymotic talk a lot about ‘accuracy’ with regard to the mc3’s. They’ve created a pair of earbuds which pick out all the instruments and vocals and throw them at your ears precisely and perfectly. They do this by not over doing the bass and making sure the volume doesn’t go too extreme. Perfect for those who do recording ect.
The noise isolation is amazing! It works wonders when no audio is even going through them. But when it is you really can’t hear anything around you, so your ears can focus all their attention on the music.
Overall the Etymotic mc3 earbuds/ headphones are not going to be everybody's cup of tea. You get very tight accurate audio while you make some sacrifices at the same time.
