Switch between LFO and EP-2

[yem]

Hola, first post.

I have a LPF and a ring mod and recently have been digging the sound of the ring mod’s LFO controlling the cut off frequency on the LPF. However, I also really like to use my EP2 to sweep the cut off frequency on the LPF. Is it possible to do both with some sort of A/B box?

[latigid_on]

You would need custom wiring or a “stereo” switch to do this (the Exp. pedal needs both tip and sleeve connections to work). Another option is to use a multiple such as on the CP-251.

[yem]

@latigid on

You would need custom wiring or a “stereo” switch to do this (the Exp. pedal needs both tip and sleeve connections to work). Another option is to use a multiple such as on the CP-251.

Is this because normal AB boxes use the sleeve as ground? Can I use a normal 3pdt switch and send the two grounds to the output? Could I rewire a standard AB box?

I’m interested in the CP-251 but don’t have the funds yet.

Thanks!

[latigid_on]

Ooops, tip and RING. Sleeve is always ground.

I’d say normal AB boxes would be mono, hence the +5 V DC would be shorted to ground.

You’d need a DPDT switch:

A   B

C   D

E   F

AB = Expression socket (tip, ring)
E = LFO socket (tip only)
CD = Output socket (tip, ring)

Wire all socket grounds (sleeves) together.
Plug a stereo cable (TRS) into the output socket, then into the desired input. Or skip the output socket and solder a TRS jack cable straight to the switch (and grounds)

Another faux pas ; a multiple is used to split a CV signal, a MIXER is used to combine more than one. The CP mixer has four inputs with an additional offset control.

[yem]

@latigid on

Wire all socket grounds (sleeves) together.
Plug a stereo cable (TRS) into the output socket, then into the desired input. Or skip the output socket and solder a TRS jack cable straight to the switch (and grounds)

I’ll need two stereo sockets/jacks right? I think the ones I have are mono.

[yem]

@latigid on

You’d need a DPDT switch:

Are you saying that I can only use a DPDT switch? Or, can I use a 3pdt switch and just use two rows?

[yem]

Would the following jack be suitable for the EP input and box output?

[latigid_on]

Hello

@yem

@latigid on

You’d need a DPDT switch:

Are you saying that I can only use a DPDT switch? Or, can I use a 3pdt switch and just use two rows?

Yes, you could use a 3PDT and just leave one row empty. I find the orientation of these a bit more tricky; depending on the type (e.g. push button footswitch) you might need a multimeter or a schematic to get the switch working properly. DPDT is much more straightforward (and cheaper!).

@yem

Would the following jack be suitable for the EP input and box output?

That looks right. If you’re unsure, plug in a TRS connector. One contact should line up with the tip and one with the ring. By design the sleeve will touch some part of the barrel to make a connection to ground. These sockets are good as you can easily follow the layers to find the correct pin.

Sounds like a fun project for the holidays

[yem]

Right on. Thanks for all of the help.

[wetpenny]

@latigid on

You would need custom wiring or a “stereo” switch to do this (the Exp. pedal needs both tip and sleeve connections to work). Another option is to use a multiple such as on the CP-251.

how could you achieve this with a CP251???

[latigid_on]

@wetpenny

@latigid on

You would need custom wiring or a “stereo” switch to do this (the Exp. pedal needs both tip and sleeve connections to work). Another option is to use a multiple such as on the CP-251.

how could you achieve this with a CP251???

Sorry, as I mentioned, you would use the mixer on the CP-251. Inputs one and three accept expression pedals. The LFO would go into another input. Because the voltage is additive for the expression pedal, you could turn it “off” by putting the pedal into the heel position.

Of course the LFO would always be “on”, but you could turn it off by unplugging from the mixer or using the input attenuator (input two).

Maybe a DIY AB box is easier