Tube Whine noise...Please Help


Hi everyone.

As a newbe to tubes I am having a problem that I need some help on. I just received my Musical Design SP-2 preamp and while it sounds wonderful, occationally there is a high frequency whine/whistling noise coming from one or both speakers. The SP-2 uses 2 6922 that the previous owners said were NOS RCA types. I want to know if the tubes went bad and needs replacing or if there is another problem that I need to look for. Thanks
speedracerucr
Hi Orind, by reseating them, do you mean removing the tubes & reinstalling them?
Jig is pulling your leg. ALL tubes operate on the principle of "thermionic emissions". Without thermionic emission the cathode would emit no electrons and the tube would just be a pretty piece of glass. The noise you are experiencing is oscillation or "feedback" caused by the physical elements inside the tube being too suseptable to external vibrations. BWT, RCA did not manufacture a 6922; they relabled. If it says "made in germany" odds are it is a Siemens. Holland or USA likely Amperex.
My expirience with the Emotive Audio Sira LE is same. I switch to the Tung Sol 5687 and got some microphonic noise, especially when touching the volume or the preamp. Well, I like the sound of the Tung Sol 5687 better so the "ring" thing doesn't matter to me. When the music plays, that's what's count.
Linkloping. Much like the 6dj8/6922 family of dual triodes ,the 5687 tends to be very prone to microphonics as well. But certainly not all of them, I concurr with your preference to the sound of the tung sol 5687 as it's far and away the best of it's type, particularly the earlier d getter version. That said: out of 11 examples in my stash,I have 4 that are dead quiet and with zero microphonics..... Speedracer,the same can be said for the 6922/6dj8 family when employed in many preamp circuits, and in many cases you need to cherry pick the quiet ones from a bunch of them. When one's preference is for using nos tubes... it can turn out to be a rather expensive crapshoot to be sure. If you "are" contemplating retubing with nos tubes,your odds of success will be far greater by substituting the 6dj8/6922/e88cc for the uprated seimen 188cc or the telefunken 188cc.These tubes, as well as the dutch amperex 7308 are the best sounding of the nos 6dj8 family next to the hideously expensive cca ,they are true low noise 10,000 hour tubes and should last longer than both you and your preamp.They do tend to be pricey though... Another economical alternative is the original nos soviet miltary 6heb or 6hev dual triodes. These are the quietest 6922 types on the planet. They are very linear tubes and have the tightest matched triode sections to boot . Not to be mistaken with the nasty sounding sovtek 6922's currently marketed to the West. These tubes are really well balanced top to bottom,very smooth with great bass punch and a vivid sounding top end void of the glare you hear with the Sovteks. Well worth searching for and typically priced within $10.00 of the Sovteks. Cheers and have a very Merry Christmas and all the best in the New Year.