Crazy idea..but is it possible?

[Tdale]

A friend of mine once asked me if I could make a pedal that could control the amount of overdrive in his amp. Same sound level, but variable amount of overdrive, using the pedal as a volume pedal.

I thought about double pots etc.. but then I got an idea..

What about wiring a pot as a variable resistor, so that the signal goes directely to the output section when the wiper is in one end, and when the wiper is in the other end, the signal goes to the OD section. That way he could adjust the amount of signal going to the OD section if the pot was mounted in a pedal......

Would it be possible, technically speaking?

Sonically speaking will probably be a different story....

Tommy

[Bob-I]

A friend of mine once asked me if I could make a pedal that could control the amount of overdrive in his amp. Same sound level, but variable amount of overdrive, using the pedal as a volume pedal.

Tim O'Brian of O'Brian amps builds his amps with a pan pedal. Push the pedal all the way back and it's 100% clean channel, push it all the way forward and it's 100% OD. in between adjusts the percentage of clean to OD.

In theory it's pretty cool, only the O'Brian OD is pretty poor.

[seulb-rd]

What about wiring a pot as a variable resistor, so that the signal goes directely to the output section when the wiper is in one end, and when the wiper is in the other end, the signal goes to the OD section. That way he could adjust the amount of signal going to the OD section if the pot was mounted in a pedal......

i tried just this in my 6v6 d-type...didn't like it. i tried pots from 500k to 2M. what i found was i could never get just a clean sound or just an od sound some of both was always present. i have since yanked it and replaced it with the standard dpdt switch. to get true mixing i think you would need another twin triode or ss device to function as a mixer. do a search, i think i have seen schemos for such posted here.

[Luthierwnc]

Tommy;

The problem is that you have a lot of exposed wire at a very delicate part of the signal chain. The beauty of the relays is that all of the cabling involved is only for the coil. The switch itself is inches away from its source and destination. For the actual electronics involved in a two channel blender pot, have a look at the McIntyre Bluesmaker schematic. Very effective but you do need to turn it by hand.

Skip

[d95err]

A friend of mine once asked me if I could make a pedal that could control the amount of overdrive in his amp. Same sound level, but variable amount of overdrive, using the pedal as a volume pedal.

Traditionally, that's what you use a volume pedal for. Put it infront of the amp and it will control the amount of overdrive.

To control the overdrive inside the amp, you could try putting an opto before the Drive pot, in series with the signal. Use a pedal to control the intensity of the LED. The lower current through the LED, the lower drive level.

[Tdale]

A friend of mine once asked me if I could make a pedal that could control the amount of overdrive in his amp. Same sound level, but variable amount of overdrive, using the pedal as a volume pedal.

Traditionally, that's what you use a volume pedal for. Put it infront of the amp and it will control the amount of overdrive.

To control the overdrive inside the amp, you could try putting an opto before the Drive pot, in series with the signal. Use a pedal to control the intensity of the LED. The lower current through the LED, the lower drive level.

The point is that he wanted to be able to control the amount of overdrive, without increasing the volume.

A volume pedal won't do that.

The pot would have to be in the OD loop, so that when the clean switch is hit, the blending pot is out of the circuit, making the sound 100% clean. Hitting overdrive would bring the blend pot into the circuit

Tommy