I use this amp hifi since 1991, is a marvel of sound quality but also power able to push my Studio4 (JM Reynauld) peak at 270watts (also capable of propelling brilliantly PA speakers equipped with 38cm 600watts ), but his best quality is the purity and the absence of distortion of the sound up to a very high volume. this amp at the time of the purchase was a candle to all models in Yamaha Onkio and value for money. Coupled to my Studio 4 I do not listen to music but I close my eyes and I feel like the artist in front of me. It's pure, it is clear is deep and powerful and yet it is only 2 times in 10 watt Class A, but what watts?? whaouuu. If I had to do it again I would take the same without question.