[HeavyBoom]

I'm looking for a bass heavy IEM. I want a full sound with emphasis on bass. I would even prefer as much or more bass than my HFI-580's give. I have narrowed it down to Klipsch Image S4 / S4i or Audio-Technica ATH-CKS55. I am open to other suggestions as well. Preferably under 100 but for perfection I will pay more.

 

[ZMan2k2]

ATH-CKS77.
 
Plenty of bass, and good mids and highs as well.  Play with different tips, and you get a variety of sound options. 
 
http://www.head-fi.org/t/604094/the-ath-cks77-big-roomy-detailed-balanced-n-i-am-not-just-talking-about-the-bass

 

[HeavyBoom]

I've thought about the 77s but I read that there was more bass with the 55s. I would go either way but I want something that has emphasis on the bass.
 

 

[ZMan2k2]

From what I read while doing research on bass-heavy IEM's, the 55's have a more muddy sound, with the highs being somewhat muffled.  You can remove the filters, which helps with the sound some, but with a little break-in, the 77s sound absolutely wonderful.  I haven't heard the 55's, but I'm going off of reports from others.