Amplifier question

[Stringmachine]

Would it be possible to have the gain of an amp to be controlled by an expression pedal insted of a knob on the panel? I have been thinking about this for a while, and it seems like a good idea to me.

Anyone tried, or know of such an amp, or have any thoughts about if this will work or not?

 

[Erlend_G]

Re: Amplifier question

Hmm, maybe a volume pedal before the pre?

Seriously, i believe you could do some rewiring, and be able to "move" the gain pot down to a rocker switch or something

 

[Stringmachine]

Re: Amplifier question

I was thinking about using an expression pedal instead of the gain pot. Using a volume pedal in front just dont do the same trick as the change come from the guitar and not the amp.

 

[bbking1021]

Re: Amplifier question

if you have a built in FX loop you could place it in there and it would act like another master volume.

 

[Stringmachine]

Re: Amplifier question

Maybe I am not being clear here.

Suppose I got a single channel amp, with 1-gain and 1-master volume. If I set the gain to the max the amp wont clean up even if I turn down the volume on the guitar. If I do it the other way around, I wont get that high gain sound.

Now if I could get a pedal (instead of the knob on the amp) to adjust the gain then I could do it.

 

[aleclee]

Re: Amplifier question

Yeah, it's doable.

The easy way would be to run the preamp signal through the pedal. The downside there is that you'll probably experience tone suckage given the long signal path. Buffering the signal might help but it'll still affect the tone and adds to the cost of the mod. There's also the issue of supplying power to the new circuit and whether your chassis has space to accomodate it.

The harder way would be to use the pedal as an expression pedal so the signal doesn't have the long trip between your amp and pedal board. The problem with that approach is that it's costly and will probably affect your tone as well. As with buffering, you again have the issues of power chassis space.

A final, relatively low-tech approach would be to rig up a mechanical device to turn the knob on your amp.

 

[Quencho092]

Re: Amplifier question

I remember when i used to jam with my friends on my CRATE MX20RC SS 1x10 amp, I used a bass kick pedal without the tip to hit the distortion button....those were the GAS less days...

 

[Stringmachine]

Re: Amplifier question

I remember when i used to jam with my friends on my CRATE MX20RC SS 1x10 amp, I used a bass kick pedal without the tip to hit the distortion button....those were the GAS less days...

:laugh2:

 

[tone4days]

Re: Amplifier question

i do this with my midi rig for the exact reason you describe .. on some presets, i have a continuous controller programmed to use the expression pedal to control the preamp gain parameter ... i even set the min/max values to my taste because i do not want it to go "full off" to "full on" , but rather about 30% to 80% ... on other presets, i use the controller to control the preamp output level (volume) parameterr in order to control the signal sent to the (ss) power amp without changing the fundemental tone of the signal ...

good luck
t4d

 

[bungalowbill]

Re: Amplifier question

I think Neil Young has a set up somewhat as you describe. He plays an old tweed Deluxe that has a footcontrolled machine that manipulates the volume knob on the amp. You might be able to find more info through Google, I remember reading about it in Guitar Player a long time ago.

 

[Stringmachine]

Re: Amplifier question

Thanks for the info, guys.

tone4days, what type of midi set up do you have?

 

[YJM_Rocks]

Re: Amplifier question

I need to get a midi setup going. My behringer is fully midi programmable and i'm getting another behringer soon.

It doesn't sound extremely difficult or anything to do what you're talking about. Probably more work than it's worth though. I guess you could add another pot for the gain on the pedal and when the switch is engaged it switches from the pot in the amp to where u have it set on the pedal. Sounds complicated, but i dont think it would be.

 

[tone4days]

Re: Amplifier question

furman power conditioner
korg tuner

rocktron pro gap (preamp) <-- older than dirt
rocktron intellifex (effects) <-- older than dirt
rocktron midimate (foot controller) <-- older than dirt

carvin dcm600 power amp

(2) boogie 1x12" cabs w/ celestions

i know i could use an upgrade on some of this stuff, but it still sounds good to me and i cant justify the $$$ outlay ... plus i'd be lost figuring out if i wanted to go with more rack gear (triaxis / 50:50) or back to a combo or head/cab setup ... i am scaired to think that i'd blow $$$$$$ on a couple of different high-end tube amps with switching between them etc ...

cheers
t4d

 

[Willis]

Re: Amplifier question

I would think you could replace the gain knob with a 1/4" jack, or put a jack next to it, and plug an expression pedal into that. Not sure how you'd wire it though.

 

[ratherdashing]

Re: Amplifier question

I would think you could replace the gain knob with a 1/4" jack, or put a jack next to it, and plug an expression pedal into that. Not sure how you'd wire it though.

Hey, I think you're on to something ... but with a volume pedal instead of an expression pedal. Also, you'd need two jacks: in and out.

Can anyone with more electrical experience take this idea and work out the implementation?

 

[aleclee]

Re: Amplifier question

Hey, I think you're on to something ... but with a volume pedal instead of an expression pedal. Also, you'd need two jacks: in and out.

Can anyone with more electrical experience take this idea and work out the implementation?

Like I said above: You can do that but there are some tone suckage issues associated with the approach.

 

[APB_4]

Re: Amplifier question

How about you put a sprocket on to the gain pot and then rig up an electric motor with a lever from a remote control car attached to an expression pedal chassis?

 

[Stringmachine]

Re: Amplifier question

How about you put a sprocket on to the gain pot and then rig up an electric motor with a lever from a remote control car attached to an expression pedal chassis?

I was thinking about that earlier. I read about someone who had their amp set up with motors connected to each pot. Seems like a hell of a job to get it to work though.

 

[Gearjoneser]

Re: Amplifier question

aleclee is right about the whole ordeal. However, It'd be interesting to get a custom amp builder to create a footswitch that has the gain and volume on the top of it.

Another option is a preamp/power amp rack setup, where you program channels the same, only some have the gain bumped up.

This post brings up the brilliant idea of an overdrive pedal that's mounted in a wah enclosure. I wonder if a good overdrive circuit could be mounted in a crybaby, using the wah's original pot as the gain knob?? Calling Stratdeluxer?

 

[DeadSkinSlayer3]

Re: Amplifier question

GJ, I've been thinking about trying that for a while. I don't think it'd be very hard, wiring wise, you'd just have to hook the drive knob up to the rocker, and wire the tone and level knobs outside. Turning it on and off could be an issue though... maybe an external footswitch?

Actually, in that case, you could just wire up a jack inplace of the drive pot, and run it to an expression or volume pedal, like Alec was saying.

I know that on old Fenders that the reverb could be controlled with a volume pedal, so this has to be possible!