This morning, I discovered how to use my favorite multi-effects unit, the Vox ToneLab LE, for looping AND soloing over the top. I found the information in a forum post on Vox's website (thanks to nmkalen in Germany.) I gave it a shot and it worked great. The looping function, though not as full featured as say a DL4, does a decent job and offers some interesting possibilities. I'm particularly impressed that I can get amp/cab simulation, stompbox, mod/delay, reverb, and looping all at the same time in one unit. And it sounds good too. :)
Here's what you do:
1) Set the Delay to HOLD.
2) If you set the expression pedal to DELAY/INPUT and put the delay as the last part of the chain (MOD/RV/DLY), you can use the expression pedal to open and close the loop. (Toe down to open the loop and put things in; heel down to close the loop, allowing you to solo over it.) You can swell things into the loop too, which is nice.
3) Switching the CONTROL button allows you to hold the loop or let it decay. (Feedback setting on the HOLD delay controls how quickly the loop decays, of course.)
If you need delay on your path in addition to looping, you can use the Mod Delay setting on the Mod pedal. Limited, but works.
I used a Fuzz setting in the PEDAL switch to differentiate between a clean looped sound and overdriven solo sound.
I was able to get some real nice sounds with this. I'll post an audio and/or video sample soon.
Too bad Vox has discontinued the LE. I think it's one of the best multi-effects units on the market.