Studiospares RED508 ABY Signal Routing Box

An incredibly versatile switching box that can be used in two ways:

- as an A/B switcher from a single input going into two outputs (like a single guitar going into two amps)
- as a single output and A/B switching two inputs (like two separate keyboards going into the same input)

It accepts unbalanced mono jack ins and outs at mic, line and guitar level.

To use the A/B switch with a single input and two outputs, plug the input into one of the "parallel" sockets and both outputs into the A and B sockets.

The parallel sockets are joined, which means the second socket can be used for a second input so combine both, or as a direct, constantly "on" output which could be sent to a recorder, effects processor or a tuner.
The extra Y switch will send the signal to both A and B sockets, effectively working as a splitter.
 

To use the A/B switch with a single output and two inputs, plug the output into one of the "parallel" sockets and both inputs into the A and B sockets.

Since the parallel sockets are joined, the second socket can be used to split the signal output.

The extra Y switch will combine both A and B inputs (not recommended for guitar signals).