Q: I’ve heard that some effects boxes can do 4-wire wiring. What is it, and why do I want it?
A: Four-wire wiring requires two things: a guitar amp with an effects loop and a guitar multi-effects processor with an effects loop of its own, such as the Boss GT-10 or Line 6 M13. The idea is that certain effects sound best in front of the amp, such as overdrive, distortion, compression, and boost, while other effects, such as delay, reverb, and chorus, sound best in the amp’s effects loop. Here’s how you set it up, using four cables/wires:
* Guitar output –> multi-effects input
* Multi-effects external loop send –> guitar amp input
* Guitar amp effects loop send –> multi-effects external loop return
* Multi-effects output –> guitar amp effects loop return
Beyond the wiring, you’ll also need to program your multi-effects so that the external loop is turned on (if necessary) and so that the effects you want before the amp (distortion, overdrive, compression) are BEFORE the unit’s external loop send in the signal path. And, you’ll need to program the multi-effects so that delay, chorus, reverb, etc., effects are AFTER the unit’s external loop return.
The advantage is that you get the best of both worlds — the effects that sound best in front of the amp are placed before the amp, and the effects that sound best in the loop placed in the loop. Yet you’re doing it all with a single, convenient multi-effects processor.