Does it go through A/D-D/A or does it pass the signal through purely in the analog domain?

It gets converted back to digital inside the empeg. However, the empeg has exceptionally high quality components inside (a Burr-Brown DAC and a 105dB signal to noise ratio). You will also gain the advantage of being able to use the empeg's built-in 20-band parametric equalizer on any songs that go in through the aux-in port.

If you are an absolute die-hard about wanting to keep both head units and not have to do the A/D--D/A conversion, then investigate the Sony XA-39II switch (available at Crutchfield for $49.95 - look here) that will allow you to use two different head units with a common amp.

tanstaafl.

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