Greetings,
This topic is based around the following Crack Manual revision, which Doc has set as a Sticky:
Page 19 - you could change 2" wire from power trans terminal 4 to 22L at the bottom of the page to 3" and connect it to terminal 14U rather than 22L. It will work either way, but this may give a slightly lower noise floor. (This is mostly correct after 4/26 but manuals labeled 4/26/10 say mistakenly 15U rather than 14U)
I have not seen any feedback or confirmation regarding this revision so I am simply posting my findings. As it states in Doc's post, this was corrected in mid-2010 so anyone who purchased a crack after that point should already have this implemented.
As far as results go, I did in fact notice a lower noise floor. When wired at 4 to 22L, noise used to be audible at around 9-10 O'clock (zero vol @ 6 O'clock). However, this point as now shifted due to wiring 4 to 14L (U was very crowded) and I cannot hear noise until 12-1 O'clock.
So there you have it, for what it's worth. Try it if you'd like... And again most of you who purchased the Crack amp in the last 3 years should already have this implemented.
Thanks.