LoFi Looper I made around the same time as the Icky Thump.
And a quick video:
http://youtu.be/QFvPXmBXy-4

t’s essentially the same as the ZVex LoFi Loop Junky:
http://zvex.com/junky.html

So it’s an analog 20 second looper built around the ISDxxx series voice chip.
It also features vibrato sounds through the use of an LFO which drops the voltage to the ISD chip.
(The vibrato feature is what intrigued me to build it in the first place!)

“depth” and “speed” control the vibrato.
I also added a “pitch” control as an alternative to the LFO which drops the voltage by a set amount and results in a detuned sound.

It certainly won’t replace my Boss RC 30 but it’s definitely got character!

If you’re familiar with schematics and want to read about the circuit, Mr Andrew has a great explanation here:
http://tech.thetonegod.com/payback/payback.html

It was quite a tough build, especially to get the LFO right as the chip doesn’t always respond as expected to voltage changes.

Regards,
Matt