I mentioned this the other day after completing mine.
Firstly, I agree with SB.
Secondly, I made two attempts to get the bias right:
1) whacked the bias to a fairly central position...things seemed to work fine...BUT...the tell-tale compression was not really there
2) crept the pot up from CCW...the effect sparks into life (just slap an open string whilst tweaking) but it still needed more gain...so I crept around just a little more...bingo: orange juice all over the place!
The vid (
http://www.buildyourownclone.com/atvid6.html ) exemplifies the sound perfectly.