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
I am using Leak TL12.1 amps that are over 50 years old!
I have changed all signal caps to Mundorf silver-gold with great results, I am using the original Paper in Oil Can cap for the power supply, they are a bit low but sound wonderfull, I was instructed by a lot of "experts" not to touch them! If you are using your amps daily they should be fine, Try to get them measured before sending them off to get fixed!
I would say you will eventually need to change them so just decide which is the best time to do it! If you change them yourself or some technician close to you, you can decide which caps to use...these make a huge diference in sound, Do you want Blackgates, Elna cerafine for the Power supply? Do you want the original (20 year old design) caps for the signal path, will you just let HK put whatever they can get cheap! Do you want to try the latest in caps that add great resolution to your amp like the Mundorf Silver-oil or Silver gold, or the Teflon Vcaps, do you want a softer sound like paper in oil caps? Do you want a more crisp sound like Hovland caps? Are you confused enough already? This is a great hobbie go for it change them and play with the sound you like!!
I have an in circuit capacitor tester that costs about 100.00. It seems to work. I tried it on an Audionics amp that has a hum. The meter shows that one of the power supply caps is bad.
Guys, here's the conclusion to this story. As I was trying to decide whether to leave my still steller performing 20.5s alone or to spring for the $$, give them up for a month and send them to Levinson for a preventive maintenance refurb, I noticed a pair of almost new Lamm 1.2 Reference hybrid mono blocks for sale on the 'Gon and bought them.

They are already broken in so I have been having fun comparing them with the 20.5s. I also finally received my Silent Running Audio Craz Twin isoRACKS. Let me tell you that the sound is glorious with either set of amps!

The Lamms are better than the 20.5s (they should be), but not as much better as you might think. It is not an apples to apples comparison, however, because I cannot use the same speaker cables because the 20.5s take only camac connectors and the Lamms take only spades. So I am using my 8 month old Transparent Music Wave Ultra speaker cables with the 20.5s and almost brand new Purist Audio Aqueous Anniversary cables with the Lamms.

The Lamms seem more powerful than the 20.5s (and are so rated), definitely have more air and a better mid bass, mid-range and treble. They also resolve more. You can hear the lead singer on just about any CD take a breath. It feels more like the performers are right there in the room with you. The sound stage is no wider than the 20.5s but it is deeper. The 20.5s have a stronger, deeper base (at least with the Transparent cables they do), and are not shabby at all in the areas of soundstage, imaging, extension. I have never heard notes decay as realistically as they do with either amps and either speaker cords in the SRA Craz Twins.

Best to all and thanks again for your comments which ultimately led me to the Lamms though none of us knew that at the time.

Ed
No, I'm going to sell the 20.5s sometime soon. I have just been keeping them to try to get a fix on the differences between the M1.2s and the 20.5s.

Ed