The thing with vintage Levinson amps you should be aware of is not the power supply capacitors but the EMI suppression caps (Rifa PME271) across the mains voltage. These apparently do not age well and fail short, creating a fire hazard. I had one of these fail on my Levinson 20.6 -- saw a wisp of smoke and shut it down, and still there was burn damage on the pcb. Then I replaced all those caps in both amps.
(Here is a picture of a 23.5 for sale as is for parts:
https://www.usaudiomart.com/details/649367673-mark-levinson-235-for-parts-or-possible-repair/images/1595023/
the fire started at the front of the amp where the power supply board is located).
When I got my 23.5, the first thing i did was to replace all of the EMI caps. It was a bear of a job because both heat sinks had to be removed to get to the front board and then there was the spaghetti nest of wiring to contend with. The power supply caps were easy to replace since they are held in place by cap brackets and the wires are connected by screw terminal to eyelet lugs. You can move the heat sinks out of the way without desoldering any wires since there is JUST enough play in the wires for the caps to clear.
Worth it? IMO you would have to spend upwards of $20k to get the same kind of low end unlimited current delivery performance.
(Here is a picture of a 23.5 for sale as is for parts:
https://www.usaudiomart.com/details/649367673-mark-levinson-235-for-parts-or-possible-repair/images/1595023/
the fire started at the front of the amp where the power supply board is located).
When I got my 23.5, the first thing i did was to replace all of the EMI caps. It was a bear of a job because both heat sinks had to be removed to get to the front board and then there was the spaghetti nest of wiring to contend with. The power supply caps were easy to replace since they are held in place by cap brackets and the wires are connected by screw terminal to eyelet lugs. You can move the heat sinks out of the way without desoldering any wires since there is JUST enough play in the wires for the caps to clear.
Worth it? IMO you would have to spend upwards of $20k to get the same kind of low end unlimited current delivery performance.