I heard the latest Mark Levinson stuff at RMAF. The Levinson is part of the very smoothed over and liquidy type of sonic signature. It's really hard to describe to people unless they have heard this. There are many other amps that have this same type of sonic signature. Your Krell S1500 is going to sound clean and neutral in comparison (although the S-1500 can definitely slant toward the bright side at times). Actualy, the new Krell sliding bias amps have this smooth/liquidy character as well.
The other side of the fence is the FET type warmth, where you have amps such as Pass Labs, Parasound, Marantz. Etc. The Vincent amps with tube input stage are also very warm sounding. It's really hard to recommend equipment to people unless they have heard these sounds and have a good idea of what they want. lol. I mean, there are a lot of people who can say "Mark Levinson is great", but it really comes down to personal preference.
The other side of the fence is the FET type warmth, where you have amps such as Pass Labs, Parasound, Marantz. Etc. The Vincent amps with tube input stage are also very warm sounding. It's really hard to recommend equipment to people unless they have heard these sounds and have a good idea of what they want. lol. I mean, there are a lot of people who can say "Mark Levinson is great", but it really comes down to personal preference.