I recently purchased a Neunaber Slate pedal for the amazing Wet Reverb effect. However all the v2 of their stereo pedal range support up to 4 effects, with 2 presets per effect. They make an external controller to control this, but its a little too big for my Pedal Train Mini. You can see a demo in the video below:
Update July 2015:
Anders Jepsen has provided some updated information if you have issues with switch:
avaliable to download here.
Update March 2016:
For those of you that have visited before, I now have a new improved circuit that just uses a SPST which means you can use soft touch switches :) It’s also much more stable when switch and shouldn’t have the random/glitchy issues that some have experienced.
Update July 2017:
I’ve since built a new ExP that ads an expression output, but still fits in the mini enclousre below. I also managed to change the hardwired Cat-5 cable for a panel mount socket. See pictures below.
Neunaber Slate: http://neunaber.net/collections/pedals/products/slate-stereo-effect-pedal-v2
ExP Controller: http://neunaber.net/collections/pedals/products/exp
ExP Specification: https://docs.google.com/document/d/1dtP4e3Sp2izZ9LJ1SC9TPAYDjfYPpU8mbfK4Lh-GG54
This is the most recent circuit I’ve used with has a switch bounce filter which allows the use of SPST soft touch footswitches:
The first incarnation used a SPDT switch for the clock:
– Neunaber don’t cover warranty for custom ExP controllers, I can’t be held responsible if you break your pedal.
– While my pedal works, I’m not sure if I drew out the circuit exactly like I made it :P
– While I’ve used a counter so that I can cycle through the effects with a single momentary switch, the same could be achieved with 2 latching switches or a rotary encoder: http://www.fk-industrie.de/en/produktkatalog/P/D/E/A/27.html
– I’ve used an up counter which cycles the effects in reverse 4-3-2-1. Use a down counter if you want to go the right way.
– When the counter sets the effect inputs to high, it also turns on the LEDs.
– I used a two color LED for L1 and L2. Mine had a common cathode, some others you buy have a common anode and may need to be connected to the +3.3V rail, with the cathodes connected to Q0 and Q1.
– Power is provided through the ExP port, I’ve just labeled the rails for clarity.
– Since the supply is 3.3V, you need a HCF logic chip (Not HCT which is minimum 5V).
– I wired the RJ45 cable directly into the box to save space, but there are some nice panel mount sockets around.
– I’ve drawn a switches only circuit here: http://jameslow.com/2014/12/01/custom-neunaber-exp-3-switches/
2 Color LED: http://www.maplin.co.uk/p/5mm-multi-colour-led-yh75s
Panel Mount RJ45: http://www.gtcontact.com/Ethernet-RJ45-Plastic-Screw-Panel-DIP90.html