Electrical buzzing sound, or else I'm imagining it


For about a year now I've either had an intermittent problem or an intermittent psychosis, and it's turning out to be really difficult to tell which one it is:

The sound from my system is often dry, reedy, really unpleasant -- even my girlfriend can hear it -- and the problem seems to be of an electrical nature. There's a sort of a buzzing noise through the upper midrange and low treble -- sort of the audio equivalent of those little trickles we used to see on the television when dad was running the electric carving knife in the next room.

If I experiment with different connections (interconnects, power cables, etc.) I can sometimes -- but not always -- make the sound come booming in, perfect, so there's no possibility at this point that what I'm hearing is speaker damage. The trouble is that the bad sound doesn't always go away when I do this little disconnection routine (I've tried every configuration, scientifically), and it always comes back, no matter what I've swapped.

One other symptom that might be interesting: when I get really lazy in my detective work and start connecting speakers to an already powered-up amp and preamp, I can hear a whisper of cloudy-sounding static, almost like the sound your ear would make if it was full of water. I know a person should never hook speakers to powered-up equipment, but in the past when I've done this incredibly stupid thing I haven't heard any such crackle.

It's not the source because it happens on different sources, and it's not any of the cables because I've switched them all out at least once. It's not RF pollution because I've treated the whole system extensively and, besides, it's in the wrong frequency band.

The mains in my house are NOT grounded, so at this point I'm thinking that it's a buildup of fault energy in the amp or preamp, but why would that affect the sound intermittently, and why only in this very peculiar, difficult-to-pin-down sort of way? Could a "bad cap" be the culprit? Any ideas are appreciated. I don't *think* I'm delusional, because non-audiophile friends can hear the difference, but on the other hand this problem has spanned several configurations of gear.
dog_or_man

Showing 4 responses by dog_or_man

UPDATE:

Last night I went to a friend's house with all of my stuff. The friend's house is relatively new construction in a quiet suburb, far from urban multipaths and overhead wires, and his listening room is carpeted and plushly furnished and big. We dutifully plugged everything in, powered up, dropped in the first disc and....

....and it sounded exactly the same. Terrible.

This experience would seem to suggest that my problem isn't RF pollution or lousy AC main power, or for that matter room acoustics. We experimented a while, at some indeterminate point trying some of his Acoustic Research interconnects, at which point the kind of musuc that the system should be making all the time came roaring in without a hint of buzz or rattle -- as if I'd just bought replacements for everything and put it all together right next to my own rig.

I suppose it's possible that the whole thing will be fixed from this day forward, simply because his cables are more forgiving than mine. Much more likely, it seems to me, is that the problem has something to do with the act of making and breaking the connections. Either there's some sort of fault energy building up in my rig and it's somehow being dissipated by the act of breaking and reestablishing the connections, or there's a cracked connection inside one of the pieces of equipment, or there's some trouble with the terminations on some of my cabling (which is all essentially brand-new, so I want to think this last possibility isn't it).

Any further thoughts, based on this experiment, would be greatly appreciated. My friend bought me two pair of these AR interconnects, on the spot, but I'd be lying if I said that I thought the magic bullet had been uncovered for a total outlay of twenty-four bucks.
Getting closer!

I just tried this exact sequence, and it worked:

1) I stopped the CD player but did not power off

2) I shut the preamp and power amp off (preamp into "standby")

3) I disconnected the speaker cables at the speakers

4) I disconnected the CD-player from A/C power, and re-established

5) I disconnected CD-player ic's at the CD-player end, and re-established

6) I powered on the preamp and the power amp (with no speaker connections)

7) I reconnected the speakers

I Pushed "play"... and everything was PERFECT.

....So what does everyone think, now?
I didn't get to keep the new ones, as my friend's system needs their extra length, but I'm relatively confident that I can rule-out cables as a potential cause because the problem recurs with the same frequency regardless of which set of my own cables I use.

A member of another forum suggested I clean all of the IC sockets with Caig Deoxit, which is at least cheap. Others seem to think we're getting closer to concluding that one or more of the connections between the various IC sockets and their associated circuit boards have been compromised.

I was totally convinced that the problem involved some sort of charge build-up and dissipation, as you have speculated, until I took the whole rig over to my buddy's house and it performed poorly straight out of the back seat of the car. Shouldn't a cold re-connection of the entire rig have started any charge build-up issues over from a base of zero?
Unless I'm way off (tell me if I am), it would seem that this most recent experiment at least isolates the problem at the CD-player, no? 'Cause I can take it out of the stack and run a crappy b-unit for a few days while someone local checks it over.