Levinson 20.5 monos - Time for a Refurb?

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.

Herman: Hey, I need to get two vintage tubed guitar amps serviced for new filter caps (at minimum) right now. But I will say that most of the original caps in each of these lasted about twice Unsound's 20 years.

Porziob: The useless comments from you just keep on coming, don't they? Nsgarch wasn't responding to the threadhead in the post you criticized, he was addressing Joemt's concern from 8/2. It's a little thing called trying to help somebody, and pseudoscience wasn't involved. If you can only get your thrills from predictable negativity and weak sarcasm, the least you could do is take the trouble to read what you're attacking first.