how to use vox tonelab with garage band

Does your tonelab have a usb interface built in?

You could just plug the 1/4" out into you tascam.

I agree with Isteveus, use the 1/4 inch line outs from the Vox into the 1/4 inch line ins on the US122.

Vox Bus is Vox's system for connecting to other Vox bus capable amps.

If you wanted to use the Tonelab as a controller for Vox bus equipped amps you could. I believe the Valtronix series uses Vox bus. A VC12 connects that way to be used a foot controller for example.

SPDIF is a digital connector, rather then an analog one.

The benefit of course is you can transmit that digital signal via a SPDIF connection without having to convert to analog and back to digital again. So one less conversion step.

Not a big deal...but nice to stay digital if you can...

...SPDIF can also be a Coax (electrical) connection (RCA or BNC type connectors) or optical (Toslink). Which are not compatible without a conversion box of some type.

Mac digital connection typically is mini-Toslink.

You could connect the Vox to the Mac digitally if you buy a Coaxial (RCA) to Optical Toslink Digital Audio Converter and a Toslink to Mini Toslink cable...for around $30.00.

But I wouldn't bother. Just run the line outs into the line in on the US122 and you should be good to go.