Pentode/Triode Switch

[tablebeast]

So, I have been experimenting with a Pentode/Triode switch on a 6AU6 in a guitar amp and I was wondering if there was an easy way to eliminate the WHUMP sound made when flipping the switch while the amp is on? Is it safe to flip the switch while it is on? I was a little worried it might stress the tube. Can I put a cap/and or resistor across the switch to soften the blow?

 

[walter]

I'm curious how that switch works. Pentode has the resistor or choke between plate and screen grid, triode has the plate connected to the screen grid. I've tried this and the difference was so subtle I took it out. And I would turn off before switching.

 

[tablebeast]

I guess it is different in every circuit and tube, but in this one witht he 6AU6 driver tube the difference is pretty dramatic, plus the distortion is different too. I like the different setting enough to keep the switch as it really makes it like two different amps. I really just want to know if it is safe to switch while the amp is on and if so how to I get rid of the WHUMP?

 

[Curtis]

Large value bleeder resistor (coupla meg ohms) across the switch poles maybe?

 

[Sorr]

Include an ouput muting system.
Simple way, triode/pentode switch and a mute switch.
More difficult, one switch that swiches time delayed relays.