I called yesterday frustrated that my Crack build did not pass signal the first time I powered it up, since I have built many other kits in the past and never had any problems. I briefly explained my issue and what I had tracked down so far and he had it figured out in just a minute or two! It was just 1 bad solder joint in the power supply section that kept the plate voltage from reaching the tubes.
It sounds great with Sennheiser 650s. It definitely isn't as bright and harsh in the high end, and has better low end too compared to my M-Audio ProjectMix I/O. That's more subtle of a difference than how much more gain it has.. being able to listen to older music (you know, the kind that actually has some dynamics
) and actually get the volume to a comfortable but powerful listening level makes all the difference in the world!