I bought this amp in 1998, it served me well until 2009. So I got a good 11 years out of it before it started buzzing at me really loudly, and I had to replace it. The build quality was very good, as with most separates it felt very sturdy. The functions where also very good, the bass boost seemed to work very well, without distorting the sound quality as you would expect from cheaper stereo's. I had this stereo bi-wired which gave it a very crisp sound and you could turn off the bass or the high end noises separately not that you would want to. This meant however that the amp could be used to only power one set of speakers. If you go for the traditional 2 wire system I believe you could power 2 separate set's of speaker's, to be used for instance in two different rooms. The sound quality of this amp was very good and over all I was very pleased with it.