Guitar Amp Tube Socket Smoking: A Troubleshooting Guide

As guitar amp enthusiasts, we've all been there - facing a mysterious problem with our beloved instrument amplifiers. One such issue is the tube socket smoking, which can be frustrating and daunting to tackle. In this article, I will share my personal experience with diagnosing and repairing a tube socket smoking issue in my early 90's Blues Deluxe amp.

The first sign of trouble was when I noticed that the reverb pot was affecting the volume even when the guitar was plugged directly into the power amp input jack. This was unusual, as normally, this connection would produce a clean, unaffected signal. As I continued to experiment with the settings, I realized that turning up the volume to maximum without reverb resulted in a low, distorted signal. However, when I raised the reverb level or engaged the drive channel, the signal became louder and more distorted.

The next step was to investigate further by putting everything back together and testing the amp again. To my surprise, the sound was very low and barely audible. The sight of the tube board connections was not pretty - with lifted pads and adjoining traces on the PCB's reverse side. It became clear that I needed to replace all the ribbon cable connections with individual lengths of wire.

Upon closer inspection, I noticed that one of the ribbon cables connecting the main board to the tube board was compromised. The ends of the bare wire were resting against each other, but they were physically broken when manipulated. This discovery led me to suspect that the issue might be related to a faulty connection between the power tube socket and the tube board.

After replacing the ribbon cables with individual wires and re-soldering the connections, I was relieved to find that the amp's performance improved significantly. The sound returned to its usual clarity, and the distortion issues were resolved. While this experience may have been frustrating at times, it ultimately taught me the importance of inspecting and maintaining the connections in my guitar amp.

In conclusion, diagnosing and repairing a tube socket smoking issue requires patience, attention to detail, and a willingness to troubleshoot and experiment with different settings. By following these steps and taking the time to investigate further, you may be able to resolve similar issues with your own guitar amp.

Guitar amp tube socket smoking