Expression Pedal Selector?

[niftydog]

Ostensibly it's very simple - you need to switch the tip and ring connections of a stereo jack plug between two sources.

The practicality is somewhat less simple. Here's why:

Most pedals with exp. pedal inputs have a switch built into the exp. pedal jack socket that disconnects a pot and connects the exp. pedal in it's place. For so long as there is a plug in that socket, the internal pot will NEVER be connected.

So, simply switching an exp. pedal connection may not be enough. If you want the pedal to return to normal operation, you need to either remove the exp. pedal jack plug from it's socket, or you will need to modify the pedal somehow.


Oh, and in the above scheme, there should be no need to switch the ground connections at all - they all should be common to each other. Just switch the tip and the ring of the jack plugs/sockets.

 

[sonicvi]

The practicality is somewhat less simple. Here's why:

Most pedals with exp. pedal inputs have a switch built into the exp. pedal jack socket that disconnects a pot and connects the exp. pedal in it's place. For so long as there is a plug in that socket, the internal pot will NEVER be connected.

So, simply switching an exp. pedal connection may not be enough. If you want the pedal to return to normal operation, you need to either remove the exp. pedal jack plug from it's socket, or you will need to modify the pedal somehow.

That is true. Although, if you had an expression pedal for each of the pedals you intend to use with this switch box then they'd be plugged into the expression pedal jack anyway.

 

[niftydog]

If you had an exp. pedal for each pedal you wouldn't need a switch box!

 

[sonicvi]

If you had an exp. pedal for each pedal you wouldn't need a switch box!

I know, but the point of the switchbox is to make one pedal take the place of three. So if ou didn't have the box you'd have to have three pedals and they would all be plugged in just like the box.

 

[sonicvi]

Smashing! Thanks. What amendments would I have to make to this circuit to include LEDs then?

To add LED's you'd need to use 4PDT switches. Or, like Niftydog said, you probably only need to switch the tip and ring and the grounds can be common with the metal enclosure. In that case you would free up a pole in the 3PDT to use for an LED.

 

[EddieG]

I know, but the point of the switchbox is to make one pedal take the place of three. So if ou didn't have the box you'd have to have three pedals and they would all be plugged in just like the box.

That was my thinking too. Whether it's a switching box, or an expression pedal plugged right in to the Boss effect pedal itself, all the effect pedal sees is a stereo input is plugged into the expression pedal input. As long as you're not planning to turn on all three effect pedals at once, and set parameters on each, expecting to be able to switch between them and have those settings remain, surely it shouldn't be a problem? And if you're switching each effect pedal off after it's use, then wouldn't it just reset itself?

So, short of rigging up an elaborate rope and pulley system, or hiding midgets in my pedal case to do the switching, this looks as though it could work. Anybody else got any opinions on this? And how would I modify that circuit to include LEDs? Bear in mind that I can follow that drawing, but designing circuits is well beyond me!

 

[Colonel Monk]

Ostensibly it's very simple - you need to switch the tip and ring connections of a stereo jack plug between two sources.

The practicality is somewhat less simple. Here's why:

Most pedals with exp. pedal inputs have a switch built into the exp. pedal jack socket that disconnects a pot and connects the exp. pedal in it's place. For so long as there is a plug in that socket, the internal pot will NEVER be connected.

So, simply switching an exp. pedal connection may not be enough. If you want the pedal to return to normal operation, you need to either remove the exp. pedal jack plug from it's socket, or you will need to modify the pedal somehow.


Oh, and in the above scheme, there should be no need to switch the ground connections at all - they all should be common to each other. Just switch the tip and the ring of the jack plugs/sockets.

+1

That's what I was trying to say in my post. It should be pretty easy to figure out the behavior of the pedals when the pedal "switchbox" isn't switched to that effect simply by plugging in a TRS jack or cable and see what happens. Likely, in the case of delay time/feedback it'll be set to zero.

Let us know what you find out Eddie!

out