I've heard that this can be done. There was a thread on here about it some time ago (in Meridian II somewhere?).

I can't recall exactly how it was done, but I seem to remember an option to configure an input to perform this function. . .

In terms of sound, as far as I know the 551 uses the same power amp modules as the 555 did and will sound pretty much the same as the 555.

Cheers,

David

596, 551 (pre-amp), 557,
Martin Logan Clarity, Rega P25, Lehmann 'Black Cube'