Did you ever have your LS-2 set to 'A+B Mix <-> Bypass' and find you sometimes wanted to switch between just one channel and the mix of both? And find your LS-2 doesn't have a mode for that? I figured out today if you add a dual-loop bypass switch you can have your LS-2 and... eat it. Or something. Anyway: Guitar -> LS-2 IN LS-2 'A' SEND -> Looper IN Looper 'A' Send -> LS-2 'A' RTN LS-2 'B' SEND -> Looper 'A' RTN Looper 'B' Send -> LS-2 'B' RTN LS-2 OUT -> Looper 'B' RTN Looper OUT -> Amp (Edit: Just realised I forgot to specify where you put the effects, it's all a bit pointless without effects! Hopefully it's obvious - between the LS-2 SENDs and the Looper IN/RTN) So... With both loops off, you get whatever's in LS-2 loop 'A' With loop 'A' on, you get whatever's in LS-2 loop 'B' With both loops on, you get the blend of both (normal LS-2 behaviour). Yes I just made my pedal board even messier.