Which? Muse model 100 amp or Acurus DIA100 integrated?

For me personally, I would go with the Muse. But that doesn't mean you would prefer the same thing I do.

Also, keep in mind that the whole point of using the Theta's volume control is to eliminate the need for a line stage. Even though most would agree that the Muse is the better sounding of the 2 amps, not running the signal through the line stage on the Acurus will make an even bigger difference.

"03-02-15: Gslone
The Muse for sure, but Acurus has made a come back recently with some nice looking stuff, so it may be worth checking into."

I thought they went out of business a long time ago. Even though I prefer the Muse, Acurus is a very interesting company. They're focus was to build the most affordable, entry level high end gear, but still keep it made in the US.