Not too long ago, I stumbled across some interesting looking in-ears on Aliexpress and Taobao called the KZ-A1. They promised subwoofer type bass and showed a frequency response graph that looked pretty good, and it was only $10. I gave it a shot, and I loved it. It really did have deep punchy bass as stated.
Then I found their two stores, and noticed they had a ton of other models, and seem to come out with a new one every two weeks. (use chrome to translate)
A lot of the shell designs are based on other iems in the market (Audio Technica, Sennheiser, V-Moda), but the use their own materials, drivers, OFC cords..etc, and they don't try to pass them off as knock offs. Each have Knowledge Zenith logos and distinct features separating them from the designs they are based on.
Here are some of the models so far:
KZ-A1 (9mm $10):
Subwoofer type bass, but clearer than a standard Beats IEM
Micro-Ring (CKN70 look, 5.8mm $10):
A micro driver (5.8mm) tuned to sound like a balanced armature. Plenty of bass.
CKM9 (CKM99 look 14mm, $12)
CKM99 type signature. Boosted bass and treble.
Most of them punch well above the price they are going for, which is normally $10-30. They are available on aliexpress and Taobao, although Taobao is the best way to purchase them. If you do not live in China, you will need to use a Taobao forwarding service such as mistertao.com and ugomark.com. There are lots of reviews from chinese users under each of the models as well.
Edited by bhazard - 1/5/14 at 11:25am