Markfothebeast

On a basic amp, the current travels from one pot to the other. I did not look at my Spider Valve to see if that's how these fancy DSP units are designed. But if it is, poor (melted) solder joint(s) on just one pot can cut out volume and cause many issues. You may not be able to see the melted solder connection with the human eye. I'd personally touch up the solder joints on all of the pot legs. These amps get HOT. If you do, ensure that the nuts holding the pots to the chassis face are tight.

I've never changed the tubes in my 2 years of ownership. The tubes are equally as bright as one another. After 30-40 minutes the tubes operating temperatures were anywhere from 350F - 385F (with head unit out of amp). One larger tube was operating 20 to 30 degrees fahrenheit hotter than the other. The inside of the chassis enclosure is nearly sealed off from any air flow. This is not good. The repeat issues I continue to read about on this forum are very similar to other electronic devices that tend to overheat. So I've decided to get a good look inside the amp and measure how much heat it may potentially generate. I recently repaired a solid state bass amp that generated enough heat to melt solder joints. The main cause was a lack of support on the PCB. The board was able to "warp" and the heat generated was enough to loosen the solder joints to the legs of a pot causing all types issues. This amp generated much less heat than my Spider Valve 112. *Test Results* High Temps after roughly 40 minutes with instrument playing, effects on, and volume at 1/8th turn: -Tubes: 350F - 385F -DSP Chip: 120F - 125F -Capacitors near DSP: 130F - 172F -Larger Caps near pots: 150F - 190F I'd forgotten the temps of the ceramic resistors but they were definitely getting hot. If I had the amp cranked up in that 40 minutes with the chassis in the enclosure it'd be much, much hotter than I measured. I would not be surprised if the components in the chassis were to exceed 220F+. The solder joints on the tube sockets look overheated like that of burnt flux. Smaller SMD solder joints, depending on the solder used, can soften or melt around 300F. This has been an issue with some video game consoles. The chassis is definitely in need of a means of air flow. I will be cutting two holes for two AC fans that are about the size of a standard 12V DC fan used in a desktop PC. The fans will be wired to the 120V AC power input with the neutral on the power switch (I think it was a neutral on the switch). And of course, fused. I will post updates when I complete the fan install.

About 2 months ago the amp cut out volume completely during band practice. Immediately, I powered off the amp to let it cool and it worked fine after that. Before buying this amp a couple years ago I'd read about overheating issues. Just yesterday (6/23/18), I was about to power the amp off and I noticed how hot the metal chassis enclosure had gotten. The backside of the chassis was nearly hot enough to burn fingers. If it was manufactured with lead-free solder there's a good chance that it may become hot enough internally to melt solder joints. I will not be using the amp in this state. This is also the first time I've used my new MKII FBV Express pedal with this amp. I also direct output the audio to a mixer and use the amp as a monitor if that has anything to do with it. I do not plan to send the amp in for repairs. I would like to know what the root cause for these amps to overheat may be. Any input or knowledge of which component is generating this heat would be appreciated. I need the amp for a gig in 3 weeks... -markfothebeast