Maybe a post on how quality of DACs can't really be understood until you get to the 10th dimension, like string theory.

Hitchiker's guide to the DAC universe ?

Been meaning to educate myself on this one. How does one tonally identify a grey versus a black background?

Without a reference to AB it's hard to pickup if you haven't noticed the difference before. It's the visual equivalent of looking out a crystal clear window versus a slightly hazy one. So one could say it's tied to clarity. Blackness is just the absence of something that keeps notes or tones from 'popping' against the background if that makes sense (think contrast ratio for TV's). You can notice this on various recorded masters where some have better dynamic range than others. Also masters that use noise reduction have a 'greyness' to them.

That said, the Yggy has pristine clarity and blackness on the digital side. The output side is where the layer of grey interferes with it. Once you hear enough DACs critically, you'll be able to tell where some of the sonic attributes are coming from.

the femtos help, but the cost increase is high. I think the big upgrade is power supply.

Honestly, I think the campaign led down the path of boutique parts and exotic solutions. Audiophiles are idiots and the best gains for me for the pulse line is with better power.

With the XFi, I found the $160 Jay's LPS to be pretty darn good even compared to the regular LPS. Heck, even a dinky 12V bench linear power supply I use is an improvement over the crappy brick.

new LH Labs Pulse Xfi + LPS review up:

http://www.audiostream.com/content/lh-labs-geek-pulse-xfi-linear-power-supply-4-lps4