Tube Amp "Ringing"


I have a Jolida SJ-502A tube intergrated amp and tonight I noticed a "ringing" sound coming from the amp. Didn't notice it when the music is playing, but when I changed my CDs and was close to the amp, noticed the ringing. Was curious on what it could be and how I can solve this problem. btw, I'm a "tube newbie", and help and suggestions would be appreciated. Thanks.
cleaneduphippy
Newbee,

Far as I can hear, the "ringing" is occuring at the amp and doesn't seem to be getting into the signal. I checked this out by turning the volume control up (slowly, of course) with nothing playing on my CDP, but with the CDP on, to see if any "ringing" was coming through my speakers. Didn't notice any. btw, where do you get the "simple rubber type rings that only cost a couple of bucks" as I'm somewhat of a believer in the KISS (Keeping It Simple) approach, along with keeping it inexpensive.
I agree with Tvad - tube dampers are no cure for sick tubes. Their primary purpose is to assist healthy tubes in presenting micro details for clearer images. They aren't what you need in this case.

A minor amount of microphonics can contribute to a soundstage appearing slightly larger than normal which on some recordings can be a positive thing. However, when they get to the stage that you are describing, they have gone past the positive effects and need to be replaced.
My amp the 502 uses the 6550 (currently using Svetland) or can use KT88. The 302 on the other hand is the Jolida that uses the EL34. Currently, in the 12AT7 positions I'm using NOS RCA Black Plates and in the 12AX7 positions I'm using Sovtex. Maybe this afternoon, I'll try to pin point which tube(s) is the "ringer". btw, any good suggestion on some good "low noise" tubes? Brashgordon, thanks for the Telefunken suggestion. Was going to get a pair, but the dealer I usually buy from was out of them at the time.
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Tvad,

You answer my question, on just how to figure "which" tube is the "ringer", now to find a pencil with an eraser. The NOS RCAs are my "newer" tubes, but nevertheless we'll see what happens. One more thing, do you have a link for TVS? Might try giving Andy a call and see what he's got.

btw, to Everybody

Do appreciate all the info you're giving me. As I said I'm a "newbie" and still learning.