I'm using 30w class A tubes to drive your Harbeths. The Mastersound comes in 2 versions - the original is 15wpc, the newer one is 12wpc and the 'p' version is 24wpc.
I'd feel comfortable with the latter - the others might be iffy, especially if your room is large.
Mastersound is a great product.
I'd feel comfortable with the latter - the others might be iffy, especially if your room is large.
Mastersound is a great product.