To my ears the 23.5 and 27.5 series amps are some of the best sounding Levinson amps ever produced. The 300 series also sound fantastic but the earlier series were best because of the 300 series capacitor issues. Levinson from my understanding fixed this issue about mid way through the 334 and later series of amps. The 300 series versus the 20 series of amps are similar in sound but some folks like the 20 series and others the 300. Personally I like both but ended up with a gently used 27.5 mainly because it doesn’t have cap issues. I would not rule out a 23.5 or 27.5 if I were you. Overall, I think Levinson amps are neutral sounding and will reproduce what you feed them. I have heard this from numerous audiophiles through the years. They are NOT dark sounding. Pass on the other hand completely opposite. I have never heard a Pass amp I liked. If you have dark or extremely warm speakers they probably are a nice fit.
