The objective for this purchase was to upgrade my cheap Koss KEB24 in-ear headphones, that I bought to replace the original Ipod classic' ones. That was a major upgrade then. Koss have rich bass, good vocals, but no highs.
My research was targeted originally to a $100 budget. I purchased Bose Tri Port and Creative Labs Zen, but, to be honest, the sound was awful. Bose lacks everything (very poor sound, I prefer the original earbuds that come with the Ipod) and Creative has no highs. I return them both to the store, frustrated.
Then, I decided to expand my budget a little more, now around $130-150 (at this time, Altec's at Amazon cost 40% less than the price I paid a few months ago at other store). I bought the 336's and my surprise was that the highs, instruments and vocal sounded incredibly natural. The bass was a little soft, but, because the superb sound at highs and mids, I decided to keep them. Then I did the experiment (this is recommended for other types of headphones and speakers, bigger ones) to have them connected for four days at a high power headphone output from my receiver at high volume, with a loop of Shakira's song "Hips don't lie" (you know this song is rich in percussions, bass, vocal), and I did not touch or hear the headphones during these days. Then I connected them to my Ipod, and my big surprise was that the bass, now is as natural as I want it to be. Big sound change.
Now I have everything, very comfortable headphones with excellent sound. The price that is now published at Amazon is a real bargain, I really will not hesitate to purchase them, because compared to others that cost as 200% more, this will, by far, sound better.