I would consider replacing you KSA-150. I had the KRC-3 Pre-Amp and KSA-50S Amp and thought that it was "IT" until last Christmas when I heard the Musical Fidelity A308cr Amp. I couldn't stand to listen to the Krell after that because the drums and cymbals weren't as natural as the MF Amp. I was told that what I was hearing was what the term "dark" meant.
I traded mine in and bought the Musical Fidelity A308cr Amp, and I very happy with it. Recently I heard the Jeff Rowland M201 monoblocks against my MF Amp, and I liked the Jeff Rowland even better. I've heard the new Krell amps aren't as dark either.
I think if you'll take some time and check around, you'll find that the Krell KSA-150 is not bad, just out-of-date. There's a lot of new stuff for the same price that you may find better, unless you like the darker sound or it fits in your system well.
I traded mine in and bought the Musical Fidelity A308cr Amp, and I very happy with it. Recently I heard the Jeff Rowland M201 monoblocks against my MF Amp, and I liked the Jeff Rowland even better. I've heard the new Krell amps aren't as dark either.
I think if you'll take some time and check around, you'll find that the Krell KSA-150 is not bad, just out-of-date. There's a lot of new stuff for the same price that you may find better, unless you like the darker sound or it fits in your system well.