Levinson 20.5 monos - Time for a Refurb?


I bought my Mark Levinson 20.5 pure class A mono blocks new in 1990. I loved them for their sound and still do. They have been 100% reliable and I have never had them back to the Levinson or my dealer for anything.

However, they are 16 years old now and except for my Magnum Dynalab tuner, they are the only thing I have not replaced in my system.

Being pure class A amps they run pretty hot.

Question is, is it time I should consider having them checked out, refurbished, capacitors and the like replaced, etc?

If so, who should I consider for this work? Levinson? They are not what they used to be when they designed and made these amps, and I'm not sure they are up to the same quality work they did back then or whether I should trust that their parts will be as good as the original. Someone else? But who?

Has anyone been through this or does anyone have any thoughts about this they can share with me?
Ag insider logo xs@2xcipherjuris
Since these amps sound fine, I fail to see what cleaning,checking & replacing fuses & connectors will accomplish that a Santaria ritual & the requisite chicken blood won`t.
I would use them til they show signs of needing work. Of course if you can have them updated to the 20.6s, it may be worth it to you.
Even though the 20.6 update was only one circuit board, Levinson no longer provides the update.

To be clear, as far as I can tell by listening, there is nothing wrong with my 20.5s. However, as I said I love them and 16 years of Class A heat is a long time and a lot of wear on the caps, if not resistors. These amps cost $12,000 in 1990 (that's like $35,000 in todays $$) and even Levinson no longer builds amps like these are built.

I just want to get them checked out and get anything replaced that needs replacing before something goes wrong and does some damage to them. Other than my Magnum Dynalab, which I don't play very often, the 20.5s are the only component in my system that I have not replaced in the last 10 months.

Thanks, guys

Ed
Common thinking, (old wives tale?) is that caps are good for about 20 years. The look-see price seems more than a bit steep. If your amps seem fine, perhaps the maintance is a bit premature. I'd suggest waiting a little while and then if you still want the amps, have them looked at. That is, unless of course they begin to dissapoint or flat out fail.
Common thinking, (old wives tale?) is that caps are good for about 20 years.

What does that mean? Do you think they don't last that long or that they last longer.

For all naysayers, if you do a little research you will find there is indisputable proof backed by numerous studies that electrolytic capacitors deteriorate over their lifetime losing both capacitance and suffering an increase in effective series resistance. It is also true that the rate of deterioration is directly proportional to how hot they get. There are also other components that can shift in value after operating in a hot environment for so many years.

The fact that this deterioration happens very slowly means that it is very difficult to discern how it affects the performance of the amps, but I guarantee they are not performing as they did 16 years ago. I have rebuilt many vintage guitar tube amps which mostly consists of replacing all the bypass and power supply electrolytic caps along with any carbon composition resistors that are out of spec. The resistors tend to increase in value. The owners, who though their amps sounded pretty good before the service, are consistently amazed at the transformation.

Given the fact these caps have been operating for at least 16 years in a hot environment, and the owner places great value on the amps, it seems reasonable to have them serviced.