The Mark Levinson 23.5 is one of the best amps ever built period. It is significantly better (major upgrades) over the 23, 27, etc. The Krell KSA 250 is also very good. There is a reason why ML upgraded the 23 to 23.5 status and the 20 to 20.5 and 20.6 status. You will find that the 23.5 is an amazing amp and will beat the pants off most high end amps made today. The internal politics in Mark Levinson company caused the company to go in a different direction. I have to tell you, that if you have a chance to get your hands on a good condition 23.5, grab it. The mid bass to upper end definition and extension is amazing and the low bass is incredible. I am hard pressed to find a amp (tube or solid state) that is its better and believe me I have looked (listened) to many. In addition, this amp can drive any speaker very well. If your friend has the amp, the best thing you can do is take it home and audition it in your system and listen for yourself. You will be pleased. Now, I'm not knocking tube amps. what I am saying is that this amp and the 20.6 are the Jewels of Mark Levinson's product line and not much out there even today can beat them. If I can find a 23.5 or 20.6 in decent condition for a good price, I would buy them without a second thought. The same holds true for some very good tubed amps I admire.
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