dog_or_man
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Electrical buzzing sound, or else I'm imagining it
dcstep
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Sounds like a grounding issue and/or a power voltage variation problem. Are Saturday afternoons worse than most other days? is it worse in the summer than the rest of the year? If so, it points to too wide a variance in you mains. A power regenerator, like PS Audio should help tremendously, if those are the signs.

Is your house so old that there's no ground at the sockets, or are you saying that you have those, but there's no ground to earth at the box? If it's the later, then I'd have an electrician ground the house for you. That will not provent 60-cycle home, particularly if the system is connected through more than one circuit. If you hook everything through a PS Audio unit, then you generally (I say generally, because grounding issues are not always predictable) will not have an issue.

What equipment do you have? If you have a turntable, how is it grounded? Does your CDP have three-prong or two-prong IEC power connection on the back?

Dave

dog_or_man
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Thanks for writing back, and it's good to talk to you again. My sources do not include a turntable. The dominant source is an Arcam FMJ-CD23 with two-prong power socket. The secondary source is an Oppo DVD player with three-prong power socket. The preamp is a McCormack MAP-1 and the power is a McCormack DNA-HT5. Cabling is by Blue Jeans and Element.

I had an APC H15 in the system for a while but it added a lot of hiss to the noise floor, so at the moment everything is connected directly to the wall. The outlets in use are of the three-prong variety, but there is no wire running from the third socket to the box, or on any of the circuits inside the box. The electrician says it's impractical to ground the system (via a dedicated AC line) because there's no room in the box.

One other thing: my particular MAP-1 preamp makes an extremely loud bang when accidentally separated from the main power while still hooked up, and other MAP-1 users report no such bang.

I've had similar problems with other gear, and sending the gear to the manufacturer has resulted in no improvement -- generally those other manufacturers haven't been able to find anything wrong -- which has inspired some close and relatively well-informed friends to speculate that I'm imagining the whole thing, or that it's room acoustics. But I really don't think so: when it's good, I can tell from two rooms away. When it's bad, I can tell from three.

dcstep
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Well, that bang is worrysome, but I'm doubting it's the issue.

Most of the APC don't convert AC to DC and back to AC like the PS Audio. They're expensive, so you don't want to buy without trying. It seems likely that there's a PSA dealer in G'ville or Jax. If so, you should try to "borrow" one (put it on your card with the idea that you'll bring it back if it doesn't work).

If you own the house, you may want to put in a new box with more capacity and a ground. A dedicated line is a big step toward cleaning up your signal. If it's just hanging on the wall in the garage, the replacement is VERY simple.

Go 'noles.

Dave

dog_or_man
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What about second-hand? I found a P500 with the multiwave II and a P600 without multiwave for about the same money on the 'gon, about $750 each. That's not an inordinate amount of lettuce for what seems like a big chunk of the problem. Also, a member of a different forum suggested I put a ground loop filter between the pre and the power, and that I buy a similar product from Channel Islands Audio that goes in the AC line and is reported to stop 60-hz hum, which I get a little hint of in my system right now. Thoughts?

...btw, no comment on the 'go noles' business -- but I do have some free sneakers I'll be happy to give you if you promise not to show up to work. ...Or would all of that constitute a 'comment', after all?

RGibran
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All PS Audio gear has a 30 day money back guarantee when you purchase direct from their website. You pay shipping only. Fairly inexpensive way to determine if this will help your situation. Best of luck.

RG

dcstep
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ouch.

I don't really have hands-on experience with the various PS Audio units, so I can't really help you there. Used is the way to go, IMHO, if you can figure out which.

Dave

dog_or_man
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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.

SAS Audio
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Hi Dog or man,

Is the sound poor in both channels or one?

Couple of quick thoughts. Could be an intermittent internal problem, high resistance connection or part such as a filter cap. Or the ICs could be intermittent, corrosion problem etc?

Cheers.

dog_or_man
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It's in both channels. You know, it almost sounds the way I imagine a "bad tube" would sound, in non-solid-state equipment (though I've never actually heard what a bad tube sounds like, so I don't actually know). But when it's there, the sound is reedy, dry, and makes analog hiss come through much louder than it really is on a recording -- all of which would seem to be what people mean when they say "squawk."

I tried some additional experiments that had me convinced for a few days that I'd isolated the problem at the CD-player, so I treated the IC sockets with Deoxit and experimented with securing the power cord a little better, etc. Everything seemed fine, but then I watched a movie the other night (that I'd seen about a hundred times) and it sounded the same way.

Preamp?

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