A few weeks ago I had some friends over. I decided to play drums and let my friends use my amps. The Roadster was a power house by all means and so was the RA100 head. However sometime during the session the RA100 started fading in and out. I did not stop to diagnose it at that time, instead I wheeled in the RA100 Combo to take its place. I have played thought he RA100 head a few times after that and nothing seemed to occur so I thought it may have been cable or guitar related (my friend usually plays with his Stratocaster with the volume set so low as it did not come to mind there would be an issue with the amp). I also thought the tubes may be on the way out (thinking power tubes). Power tubes appear to be fine. What did occur today was the Hi/Lo channel faded, it can be heard but sounds thin. The Clean channel is unaffected and still loud and strong. Not using the power soak but did turn it on to check. Master volume for Lo and Hi do not seem to do very much at all. Tone controls are working.
Just for diagnostic purposes, I let the amp cool down and decided to replace all of the tubes. I had kept the one's that were in the amp marked so I can return them. Problem is still there. Disconnected the footswitch, turned off the reverb. changed power settings. Clean channel is strong and stable but Hi/Lo channel is attenuated. At least that rules out V3, V4, V5, V6, V7 and the power tubes. I thing this time I will have to pull the chassis and inspect components. It could be as easy as cleaning the metal dust off the circuit board. That would be my major complaint on any amp that uses the aluminum shields that twists into place, especially when the tubes point upward. I am sure I will find the issue. Just wondering if anybody else has encountered a similar issue with the Hi/Lo channel.
Just for diagnostic purposes, I let the amp cool down and decided to replace all of the tubes. I had kept the one's that were in the amp marked so I can return them. Problem is still there. Disconnected the footswitch, turned off the reverb. changed power settings. Clean channel is strong and stable but Hi/Lo channel is attenuated. At least that rules out V3, V4, V5, V6, V7 and the power tubes. I thing this time I will have to pull the chassis and inspect components. It could be as easy as cleaning the metal dust off the circuit board. That would be my major complaint on any amp that uses the aluminum shields that twists into place, especially when the tubes point upward. I am sure I will find the issue. Just wondering if anybody else has encountered a similar issue with the Hi/Lo channel.