subdirectory_arrow_left subdirectory_arrow_left Tube Guitar Amp Heads
Gear Tube Guitar Amp Heads {{currentManName}}swap_horiz Crateswap_horiz Find a manufacturerkeyboard_arrow_down

BV300HB Bias - forum Crate Blue Voodoo BV300HB

I have a BV300HB and the schematic and some know how...I went to set the bias on a new set of 6550's. The specs say set to -120mV to ground on tp #1.
It's a negative bias setup so reducing the voltage to say -110mV would make it run hotter...I had the new tubes in it for a couple of months with no problems but i thought hey...maybe I can make it sound better by heating it up a bit. So I broke out the DVM and went to set the bias and it reads -88mV! should have exploded way back. The tubes do not glow/get hot after several hours on. Why would it be out of range like this? Any ideas or things to try?
Do you happen to have the bias setting for tp 2 as well?

Latest questions in « Tube Guitar Amp Heads »