Things weren't working quite right, so Rian from These People Here decided it was time to spiff up his Music Man HD130. This particular amp started it's life with the older 12AX7 phase inverter. At some point in the 70s (remember those?) it was updated with the newer solid state drive board. Someone had replaced the power tubes and tried to bias it using the older method. With the solid state board installed you can spin the old bias pot like the wheel of a tall ship avoiding the Kraken and it won't make an ounce of difference. The tremolo effect needed some coaxing as well. We replaced the toasted EL34s with the correct 6CA7s, set the bias properly and the difference was immediatley noticeable. 130 watts of spacious, clean tone. Turns out it makes a surprisingly good bass amp too!