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Dramatic Visible? Power Issues -- What Next?

My system has developed a new problem. It strikes me as whole lot more complicated than it likely is, but any input from those more knowledgeable than I (not too hard) would be greatly appreciated. This one’s got me worried.

Start simple: after being on for anywhere between 1/2 hour to two hours, the system develops a loud hissing, much like a very strong tube rush.

Complicate slightly: the volume of this "rush" is inversely proportional to the volume setting at the preamp. Which is to say that above a certain (variable, but too loud for listening levels) volume setting, the "rush" disappears. At a zero volume setting, the "rush" is the loudest, which can be very loud.

Complicate further: the volume, consistency and pattern (yes, pattern) of this "rush" changes. Sometimes it's constant. Sometimes it pulses. Sometimes it builds to peaks and then snaps to silence, only to build again -- sometimes rhythmically, sometimes erratically. It's in both channels. Preamp is tubed, amp is solid state.

Complicate yet more: it's tied to the power system and draws quite a bit of power. Yesterday, at zero volume and no input, the rhythmic "rush" pattern caused the lights in my apartment to pulse along with the soundtrack. (There is a Richard Gray Power Block between the system and said lights). This is when it started to scare me a bit. If that’s not enough, the amp clips while powering down and has blown internal fuses twice in as many weeks.

Prognosis? Clearly, a problem. Something is storing and then leaking a whole lot more power than it ought to be someplace it definitely ought not to be. This problem has been happening (rarely and subtly at first, but recently far more dramatically and without fail) ever since I got the preamp, so that is my first suspect. I have another preamp that I intend to swap in before I try anything else. In the meantime, any thoughts or pointers would be greatly appreciated. Looks and sounds like there is a lot of errant power in there someplace -- and I’d hate to stick my finger in the wrong spot...
mezmo
gs5556
769 posts
 
...and worried you should be. I would unplug the sucker immediately and place a phone call to the preamp's mfr tech support. Dimming the lights??!!
mdomnick
331 posts
 
Wish I could offer better advice than this, but call a priest.

Keep us posted of your fix, I'd like to hear what could cause that. It seems to me the amp is the most likely culprit with a bad capacitor or resistor???? But then again I don't know jack about that stuff;)
natalie
404 posts
 
Talk to the factory.Maybee bad tube,bad fuse bad cap bad reistor all of the above.
jadem6's avatar
jadem6
1,071 posts
 
Don't you just love high end audio? I would unplug it and have the amp and pre-amp checked out. You could do some real damagew to the remainder or your system if you keep playing with it. Take it from a guy who fried a cd player, pre-amp, amp and speakers!
mezmo OP
516 posts
 
It's definitely the preamp. Swapped in the old one and everyone is getting along just fine now. Time to talk to the good folks at Rogue.

What I really love about this "high-end" stuff is remembering the cheap old Yamaha and Infinity system I had that never once stopped making music (and nothing else) for ten years. Over the past three years of "high-end," I've replaced a driver in a speaker myself (with parts from the manufacturer), sent an amp back to the factory to have a bad muting switch replaced, and now the preamp is on the blink (not to mention the countless hours on DIY wires, tube rolling, and just general tomfoolery). Sure, it all sounds a lot better, but it seems to spend an inordinate amount of time not sounding at all, what with all the "maintenance." What more, the stuff seems so damn fragile, half the time I'm almost wary to use it -- say I want to listen to something for 10 minutes before running out: is it worth firing up the tubes for 10 minutes? I hate to turn it on and then just turn it off again? can't leave the thing on because lord only knows what it will do while I'm gone? (Used to be I'd leave the amp on for weeks at a time, now I come back after two hours and it's blown fuses in my absence). Call it a crisis of faith, but I'm questioning my trust in the fickle gods of "high-end." Maybe I do need a priest....

As for dimming the lights from the preamp -- yep, not good. Not good at all. However, at the risk of talking out of school, I have to say that at the time it decided to put on the show I was approximataly 12 hours into what ended up being a 25-hour first date. So, without more fanfare than a simple "humm, that can't be good," I just shut it all down and didn't mess with it again before switching out the preamp alltogether last night. All things considered, I'm sure it's for the best. If I didn't have something else to distract me at the time, I might have attempted to take the fool thing apart and likley would have killed myself in the process. Shoot, this gal might just have saved my life . . . imagine.
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