Why would you run one integrated amp into another? Seems you're just wanting to complicate things unnecessarily IMO, especially if based on some dude on the internet saying it would be "more musical" which is such a silly descriptor in any case when describing hardware. Could make a difference to the speakers as to which amp perhaps. If your Hegel has something like a main in you could use the tube thingy as pre-amp. You could do that vice-versa if the integrated tube amp has such. You cannot combine the output of the two amps, tho. I'd pick the integrated amp you prefer and just use it.