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FS: Homemade ABY/passive mixer/effects loop pedal... (come look!)

Discussion in 'For Sale: Effects and Pedals' started by christopherogut, Feb 13, 2014.

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  1. EDIT: SOLD (along with a modified EHX Freeze) to stodgers!

    Hello pedal junkies! I was playing with an EDM/electronica group until recently and had to build my own pedal to accomplish something special to add some noise to the mix. Well, I'm not playing with them anymore, sold the pedal (ZVex Seek Wah) that I made this to mate with, and now feel it needs a loving home. It's made with a bunch of good components and a solid housing all purchased through Pedal Parts Plus. The 3PDT momentary switch is from Bitches Love My Switches. It's literally mechanical switches and creative wiring, nothing digital!

    Basically, this thing splits your signal into two effects loops each with a send and return. The one loop, the normal one, is either active or bypassed with the left foot switch and the LED responds accordingly (green = active, red = bypassed). The left and center knobs control the return volume which is passively mixed to the output so you can adjust the volume after your loop versus the dry signal. The 9v battery inside is solely for lighting the LED, which comes on when a cable is plugged into the input jack.

    The second effect loop is special as it's isolated. The right footswitch is a 3PDT momentary switch which performs the magic of momentarily allowing the input signal to send to the effect loop while simultaneously making a trigger signal fed to a 1/4" mono jack. The return volume is controlled by the right knob and is then passively mixed with the other loop. I did a quick diagram to roughly illustrate what's going on:


    Here's how I used it: I'd connect my normal pedals to the normal effect loop. I'd connect an EHX Freeze pedal followed by my ZVex Seek Wah to the isolated loop and then run a cable from the trigger jack to a jack I added to the Freeze (in parallel with its footswitch) and run it in latch mode. When you stomp the left footswitch, it triggered the Freeze to capture and temporarily let the audio signal pass into the loop to get 'Freeze'd' ad infinitum. That way, I could keep the Seek Wah from adding its effect to my normal signal and would only let it modify the Freeze infinite loop.

    A cool side-effect of the pedal is that there's a bit of crosstalk between the two effects loops due to the fact that the output is simply summed by having the three pots in parallel. I would routinely capture with the Freeze, then jump the volume up and let a bit of the dirty signal get into a bitcrusher pedal and delay on the normal effects loop for some wild runaway noises. I'm thinking a few diodes could help with cleaning up the crosstalk but it's honestly a cool glitch! The pedal also has a 'tuner' output which is effectively the dry signal.

    I bet there are similar ways to accomplish the same thing and may indeed be fancy boxes which can do the same thing, but hey, I had a lot of fun building this pedal and was super-happy when I hooked it all up and it worked just like I wanted! I had plans to build more (including one for my pedal-junkie guitarist and a few possibly for TB) but that never happened. Hate how it looks? I just used a silver Sharpie so it can rub right off if you really try. Also, contrary to how the pictures capture it, it's metallic purple.

    I'd like to get $40 shipped for it in the 48 States. I would be stoked to know you can put it to good, creative use!

    If I get a bunch of interest maybe I'll make a few more or at least share the schematic (which is written on paper at the moment, if I can find it).

    Feel free to ask questions here or shoot me a PM. Thanks!

    (click the pics for full-size)






    Last edited: May 19, 2014
  2. bump
  3. omie


    Apr 5, 2011
    I don't understand what the trigger output does... Assuming I don't have a modified EHX freeze. Also, will the battery drain if ithe pedal remains plugged in when not in use?

    Cool build.
  4. The trigger is basically like hitting the foot switch on the Freeze (or any other pedal with a foot switch input) so that when you stomp on the right foot switch on my pedal, you snag some audio to freeze and then infinite loop/reverb/echo/whatever and only momentarily let the audio send to that loop. When you let up on the switch, you've isolated the send but still let the pedal chain on that loop return signal. I did it this way so that a ZVex Seek Wah I had could be fed from a Freeze in latch mode without sending my live signal through the Wah, too, so the Wah just acted on Freeze'd signal... and every time you hit the switch on my pedal it'd trigger the Wah and allow signal to pass to be Freeze'd... ya dig?
  5. bump from the dead... still available. someone must have a pedal board that could benefit from some isolated looping...
  6. stodgers


    Jul 10, 2005
    Columbus, MT
    PM coming your way.

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