One thing I have noticed over the last week or so of listening is that the I-Phone just does not have enough "umph" to serve as an adeqaute pre-amp. When I hooked my Onkyo receiver up to the amp and used the pre-outs, I was really able to push the amp and the sound was great. So, I decided to hunt around for a little pre-amp (or headphone amp) for the amp I built. I finally decided on this one:
It's a tube pre-amp/headphone amp, and it looks like a tweaker's wet dream. Some guys on another board had a chance to play with it and some have even modded it a bit:
It's on it's way from Hong Kong right now, but it won't be here for a couple of weeks. Has anyone here had any experience with this unit? I know some of you are into headphone amps.