I had a recent issue with a Two Rock Exo15 that was blowing rectifier tubes. All the caps looked and measured good. On a hunch I decided to replace them anyway. They were hotmelted onto the board. I generally clip the + side of polarized parts to help me remember which way they go. When I did and got one loose from the hotmelt, it just fell out, as in the - lead wasnt soldered in right.
The hole board a single sided board with plated thru holes. All parts were soldered only from the back and it didnt look like they let solder wick all the way through to the part side of the board. When the cap was installed, it must have been barely soldered in. Then over the last year of gigging, that cap worked its way loose. I replace all the power supply caps and resoldered both sides of the power supply board. Added steering diodes to the tube rec so they are absorbing the - swing in an effort to take some of the stress off it. The power supply is solid now and a lot closer to the voltage range I expected to see in this amp. Re-tubed the amp, biased it up and it sounds tons better now . Probably will be far more reliable too
The hole board a single sided board with plated thru holes. All parts were soldered only from the back and it didnt look like they let solder wick all the way through to the part side of the board. When the cap was installed, it must have been barely soldered in. Then over the last year of gigging, that cap worked its way loose. I replace all the power supply caps and resoldered both sides of the power supply board. Added steering diodes to the tube rec so they are absorbing the - swing in an effort to take some of the stress off it. The power supply is solid now and a lot closer to the voltage range I expected to see in this amp. Re-tubed the amp, biased it up and it sounds tons better now . Probably will be far more reliable too
