Two, tube mono blocks and a Yamaha as-100 integrated I use as a pre amp. This way all my equipment is used all the time, plus I can isolate any issues by using the integrated amp to test outputs. I have been caught in the past with no way of verifying or isolating problems - one channel bias, noise etc. After 40 years of hi-fi I do value a balance control as well, after years of no tone or balance.