2. amps-preamps
  3. 139131-120014

Randall RG50TC tube amp issue

Hi there. My tube amp - Randall RG50TC (I have 2 of them) started to:
1. sound very thin even on high gain - it's like very low distortion all the time
2. if I palm mute and strum a chord the sound coming out of the amp "vibrates". Like an echo
I have changed pre-amp tubes, I have a sticker that says position (1, 2, 4) 12AX7. Position 3 sticker is missing. I found on the web it is the same so I hope even if I have an "older" model it should be the same.
I put everywhere 12AX7 various combos (1xEX7, 3xShuageng) - all new. I tried combination with different old tubes I have, keeping the new one I just bought in V1...
The distortion was there but after a while it is weak again. And the vibration sound is there all the time. Any ides? Power tubes - do they influence anything? I mean the amp is loud as it should be. I haven't changed the power tubes for 10 years. Both amps behaving the same.
Thanks!
pumukly
roberjerman
4,319 posts
 
You are on the WRONG forum! This is a HI FI forum - NOT about guitar amps!
roberjerman
4,319 posts
 
Owning tube guitar amps, I'd say that your output tubes are kaput! They don't last forever! A 1000 or 2 hours usually, depending upon biasing and usage. Get a new matched set and most important - set the bias voltage correctly for the output tube type used. DO NOT swap output tube types in your amps (compared to the original set the amps were designed for). NO EL34's for 6L6's ... etc!
roberjerman
4,319 posts
 
Those poor guitar amps! 10 years on those output tubes! Get NEW sets and bias them correctly.
More to discover