2. amps-preamps
  3. 1021263574

Pinging sound from Preamp

I just re-arranged my system, and you got it, the audio gremlins have struck. Immediately after start-up mute cycles off on my BAT VK3i, I hear a rhythmic "ping" from the pre and through the speakers. After starting CD, I cannot hear it, then after a while (30-45 min) I start hearing it through speakers over (lounder than) the music (which is at a fairly low volume). When I mute the pre it goes away, and it is present regardless of source selected (even if source is shut off). Any thoughts?
128x128swampwalker
gumbydammit
186 posts
 
The audio gods have rained on you :>(

I am interested to know what you find.

Once, on an old pre, a similar problem was a flake of metal in the selector switch. Good luck.
vantageaudio
182 posts
 

Had a similar problem with an amp. Turned out to be a faulty capacitor in the mute/protection circuit. I don't know enough about the BAT to comment on what may be the cause of your problem, but thought I would share my own experience.

Regards, Richard.

swampwalker's avatar
swampwalker OP
5,138 posts
 
After re-reading my post, maybe I should say pinging starts AFTER pre-amp goes thru start up and is no longer muted, i.e, when pre-amp is muted, no pinging, when pre-amp is active, pinging is heard. I've swapped out the 6922s to a new set of NOS Amperex and its still there; now on to the 6V6s (which don't have many hours on them).
bob_bundus
1,834 posts
 
Mike that sure sounds like a microphonic tube; seems like you're on the correct path toward isolating it. Very strange that it suddenly appeared in the manner that it did, & that changing tubes didn't help; really makes you wonder?
More to discover