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dog_or_man
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Back to ask again! (long! sorry!)

If you recognize the user-ID, then you know the problem I'm about to describe because I've been yapping about it in these forums, on and off, for *years*. I'm only in here to try again because everything I've done so far to try to fix it has resulted in just more credit-card bills.

The sound is perfect for the first twenty or thirty minutes -- always has been, and I always think I've fixed whatever's wrong -- and then, gradually, the sound becomes reedy and increasingly sibilant in the upper midrange and apparently "over-modulated" right around the midrange-tweeter crossover.

If I shut everything off and reconnect everything, the problem often goes away for another twenty or thirty minutes, but not always.

It can't be a problem with components or speakers because everything in the chain has been repeatedly replaced, and many configurations have been sent off for service and returned with clean bills of health.

I don't think it's RF pollution because I've encountered the problem at a friend's house, and fixed it doing the same thing, over there: reconnected everything and had great sound for... twenty minutes.

I don't think it's a cracked RCA input socket because the problem has spanned several configurations of equipment.

I don't think it's a bad interconnect because the problem has spanned several configurations of cabling.

I don't think I'm delusional because non-audiophile listeners have commented on both the unpleasantness of the sound before reconnection, and the improvement afterward.

At all events, something seems to be "building up" in the signal path, somewhere, and the act of severing all the connections seems to cause whatever that build-up is, to be dissipated.

Lately I've been trying to fix this by... well... *reading* -- about everything from PS-Audio Humbusters to Audience Adept Response power conditioners and back to the XDC power filters by Channel Islands Audio. Trouble is, I'm cleaned-out financially and I just really don't feel like spending any more money before knowing with a bit more certainty that more dollars spent will point me more definitively toward getting to the bottom of this. Are there professionals who can help to diagnose the problem, and who are then also knowledgeable enough about the industry to recommend the proper fix?

Current system configuration: (many, many others have been tried!)

McCormack MAP-1 and DNA-HT5, connected directly to dedicated AC circuit via Signal Cable power cords

Arcam FMJ-CD23 connected directly to nearby, undedicated AC circuit, via signal cable digital power cord

Sony BDP-S550 blu-ray player and Panasonic TX50 plasma TV, connected to APC H-15 power supply, which is in turn connected to the undedicated AC circuit via Harmony power cord

Salk Songtower QWT speakers, front L and R, Linn Trikan center channel, Totem Mite-T rear L and R.

signal cable interconnects, element cable cross-connected speaker cables.

Thanks again, everybody.

Dave O'Gorman
Gainesville, Florida

Buddha
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Re: Back to ask again! (long! sorry!)

Hi, this is a fascinating thing.

Does it happen at all other listening venues, or just the one friend's?

Also, have you noticed it on any full range speakers that lack crossovers, like elctrostatics or full range cones?

No such thing as too much info. Keep filling in more and more observations!

Jan Vigne
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Re: Back to ask again! (long! sorry!)


Quote:
I don't think it's RF pollution because I've encountered the problem at a friend's house, and fixed it doing the same thing, over there: reconnected everything and had great sound for... twenty minutes.

Did the problem exist at this friend's house before you noticed it? Did it persist after you left? How long had he owned the system and when did this problem first make itself known? Had your friend tried anything to solve the problem?

You say you don't think it's RF pollution but have you tried to minimze the possibility of RF pollution in your own system?

This problem always occurs or sometimes occurs?

dog_or_man
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Re: Back to ask again! (long! sorry!)

Thanks to all who've posted so far -- will respond in detail approx 9:30pm, eastern. Teaching a three-hour class right now and they're just having a ten-minute break. Don't forget about me!

wkhanna
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Re: Back to ask again! (long! sorry!)

Maybe it is your hearing. Some frequency or frequencies may be irritating to you. It may take time for the discomfort to develop, and after you shut the system down to investigate, the respite allows your hearing to

Buddha
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Re: Back to ask again! (long! sorry!)


Quote:
Maybe it is your hearing. Some frequency or frequencies may be irritating to you. It may take time for the discomfort to develop, and after you shut the system down to investigate, the respite allows your hearing to
RGibran
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Re: Back to ask again! (long! sorry!)

I thought Charles Hansen of Ayre saved your love for audio in ten minutes?

RG

dog_or_man
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Re: Back to ask again! (long! sorry!)

Hi, Buddha. The gear has only been tested at the one friend's house and hasn't been tested with full-range electrostatics or cones. As for more observations: There is a gigantic central A/C and furnace air handler in a closet, just 28" or so from the left-side speaker, albeit on the other side of a plaster wall. Could the humongous coil in the electric motor of that device be causing some sort of "build-up" of something extraneous in either my gear or my cables? Will answer other queries with separate posts.

dog_or_man
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Re: Back to ask again! (long! sorry!)

"I thought Charles Hansen of Ayre saved your love for audio in ten minutes"

...so did I!

dog_or_man
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Re: Back to ask again! (long! sorry!)

Hi, Jan Vinge. The RF issue has been dealt with in a haphazard way (is there any other, when it comes to RF), mostly involving ERS paper and self-adhesive copper sheets, to no lasting benefit. The problem existed at the friend's house before I disconnected and reconnected everything, and then didn't recur until after I was home again (though we didn't listen there for very long, in-between). My friend doesn't have (or at least doesn't seem to have) the same problem with his own rig -- though I can't be sure because I haven't done much serious listening to his rig.

michiganjfrog
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Re: Back to ask again! (long! sorry!)

No one can accurately diagnose the problem on-line, only guess at it. You need to troubleshoot more, before you start fixing things that ain't broke (which as you now know, is an expensive proposition). It sounded to me like it could be an amp problem, until you said it reoccurs across different components and cabling. I take it that means you already tried just changing the amp, and keeping the rest of your system intact? If so, have you tried moving your system to a friend's house? If it doesn't occur at another location with the same components and cabling, that might tell you whether its a power/RF pollution problem.

Addendum: After a more careful read, it seems like you are saying you migrated your entire system to a friend's house, and the problem remains. If so, this could only be solved by Rod Serling, because something doesn't seem right in all of this, if you changed all components, and locations, and the anomaly is heard by others at different locations with different components. As Buddha says, more info is needed. If the location you migrated your system to is really a different location (ie. not just next door), then I don't see how RF pollution or anything similar could factor in - the anomaly is way too specific for it to be that. Maybe if you simplified the system with just amp, source and speakers (and necessary cabling of course), and started from there; switching components and locations if necessary, to try to eliminate, and thus identify, the exact problem.

dog_or_man
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Re: Back to ask again! (long! sorry!)

Michigan, your "addendum" paragraph is really getting to the heart of the frustration, but let me qualify the perplexity by clarifying what we tried: I took the amp, preamp, and cdp to the friend's house (across town, though still with the same municipal power company at the pole), and we both heard what I'm used to not liking. Then we broke the connections and tried different IC's and everything seemed to sound glorious. We listened for a few minutes and I went home, where everything still sounded glorious... for twenty minutes. We never got the problem to recur *at* the friend's house, and the friend has since recanted his own detection of the problem as the result of suggestibility.

I should also tell everybody one more thing.

Sorry this is coming out in dribs and drabs, but I have a hunch that this might be an important detail: I started shoveling money at my stereo in the first place because an old configuration of gear and speakers developed this *bizarre* characteristic that several different techies were unable to recreate on their own benches: After extended listening, the left channel would develop a "whooshy" kind of noise, almost like the sound your ear makes when it has water in it, and would attenuate in volume, eventually to zero.

If I went to the back of the stack and wiggled the left-channel IC between the pre- and power amps, I'd hear a series of loud pops in that channel, and then everything would work just fine again, for awhile. As I say, it was for this reason that I started swapping-out gear in the first place, but what the ancient problem and the current one seem to have in common is a tendency for "build-up" to be dissipated by mechanical processes at the back of the stack.

Does this shed any new light?

mrlowry
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Re: Back to ask again! (long! sorry!)

Have you bought a large portion of your gear from a knowledgeable and competent dealer? If so it wouldn't be out of line to ask them to stop by your home for a little on-site trouble shooting. That's really the best answer. It's very difficult to diagnose intermittent problems with no obvious logical source without being hands on, as I'm sure that you've learned.

JSBach
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Re: Back to ask again! (long! sorry!)

This is a wild stab in the dark but it's possible, if your interconnects are somehow mechanically connected to a printed circuit board inside your amp, that 'wiggling' interconnects is jiggling a connection/ disconnection on that printed circuit board. Sometimes when manufacturers use glue under output caps to damp down vibrations, over time that glue can become conducting and affected by minute flexing of the PC board.
As I said, this is a wild, wild guess but my instincts tell me it's something like that which is the problem. The worst nightmare is intermittent faults like this that fail to play up when you get the gear onto a technicians' bench.
By the way, does the humidity in your listening room vary to any great degree?
I'm stabbing in the dark again here.

dog_or_man
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Re: Back to ask again! (long! sorry!)

I've spoken with someone via telephone, who saw a similar post on A-asylum, and he thinks that the situation is difficult for me to describe because I'm unwittingly mixing causes and effects. If, for example, the house power had faulty earth ground and/or substantial DC-offset, then it's possible (according to him) that these problems could be compromising the performance of assorted gear, in ways that are similar but not entirely identical, because the gear is dealing with the problem in ways that are informed by its design.

The story of the whooshing sound in the (now long-since sold) Parasound gear could be a perfect example of this: the problem was *plainly* audible even to total non-enthusiasts, indeed if left to its own devices would cause the entire left channel to cease making any noise, but in three different trips to service (two local and one to the manufacturer) no one was able to replicate the trouble on their bench.

Meanwhile, someone in another forum has said, "You can't get a 20-minute lag from DC offset problems; they'd be immediate."

Follow-up thoughts?

Zman9001
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Re: Back to ask again! (long! sorry!)

I may not be qualified to answer this question but Ill certainly take a shot at it. You might want to find some electrical engineers to help you out with this one. If you have a highly capacitive or inductive load in your power system it could be causing problems in other equipment (ie stereo) im guessing that this happens anywhere in your house and not just in your listening room, right? Is it feasible to try your system at a neighbor's house? Do you live near any heavy industry (factories, etc)? I suggest unplugging everything in your house I mean EVERYTHING including turning off the circuit breaker that feeds your furnace/ air conditioner/ electric stove, anything with a dedicated circuit and see where that gets you.

Jan Vigne
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Re: Back to ask again! (long! sorry!)

I'm confused by all the back and forth of this thread. Tell me if I have this straight.

1) Every piece of equipment you have tried has resulted in the same problem? Or, in other words, no equipment change ever resolved the problem even momentarily/temporarily?

2) The Parasound had a similar problem to the current system but also had the whooshing sound.

3) The current system has no whooshing sound but has a problem of dissonant sound quality which always appears after approximately 20 minutes of play time?

4) The onset of the current problem is immediate or gradual?

5) The problem only exists in the left channel? Only the left channel front and rear or only the left channel front? Or all channels?

6) The problem exists with all source inputs or only certain source inputs?

7) The system receives AC from two different locations, one a dedicated line and another a non-dedicated line with a power supply in line?

8) You have various power cables running to all equipment, some stock and some aftermarket but all cables are from different manufacturers?

9) Your speakers are not matched sets front/rear/center?

10) Your present system displayed this problem when it was used at a friend's house, though your friend can't or won't now say that it occurred there?

11) Only the whooshing sound from the Parasound has been heard by others?

12) None of the techs have had the entire system on their bench at the same time? What pieces have been checked by a technician?

If you have had problems that have persisted through various component and cable swaps, then I would begin to look at what has remained constant in your system throughout the entire process. What would that be? The rack? The AC lines? The room? What else?

If I am understanding most of this correctly, here's what I'd suggest at this point; strip the system down to its bare essentials and move it to another room. Lay it out on the floor and use all of the original power cables and no power conditioners. Use the most basic interconnects you can find to make a two channel system operable.

Listen for the results and report back.

In most instances I would agree that DC offset problems would not be intermittent. How loud do you listen?

dog_or_man
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Re: Back to ask again! (long! sorry!)

Will reply to recent follow-up queries in detail, later today -- thanks everybody, and don't forget about me!

dog_or_man
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Re: Back to ask again! (long! sorry!)

Jan, thanks for all your effort in helping me with this. In answer to your questions:

1) New gear solves the problem temporarily. It usually takes longer, the first time there are new boxes in the stack, for the problem to recur. After that we're right back to the same "period" on the pendulum.

2) Yes -- similar in the sense that wiggling the appropriate interconnect on the rear apron caused the problem to dissipate and then not be repeatable until it recurred on its own.

3) Yes. Though 20 minutes is a mean-value, with lots and lots of variation on *both* sides.

4) Onset of current problem is gradual after connections have been broken and reestablished. First recordings sound not quite their best, then not quite up to snuff, then not quite listenable, then terrible.

5) With the Parasound gear it was only in the left channel, but now the problem seems to be in both channels, equally, though it's more difficult to verify because it's less easy to isolate sonically. Between the Parasound gear and now, incidentally, I also damaged two pairs of speakers at relatively moderate listening levels, both of them in the left channel only.

6) All source inputs, equally and immediately once the problem exists at all.

7) Correct, though that configuration is only the most recent of several that have been tried during all of this, and to that extent has been "ruled out" as a possible cause.

8) All of the power cables are aftermarket and all of them are made by Signal except for the one running from the power supply to the undedicated line, which is a Harmony.

9) Correct.

10) The friend in question has had trouble "admitting" that there's really a problem, perhaps owing to some off-topic issues in the dynamic of our friendship. What happened that night (and on several other occasions before and since) is that at the time he's said, "Yes, Dave, that's really unpleasant to listen to: something's wrong," and then, a day or two later, he either says, "I don't remember it that way," or "I was just suggestible." point being, he heard the problem, at his house, and he heard it go away at his house after we swapped-out some IC's.

11) Not exactly. Others have heard the more recent unpleasantness, too, and the remedy was demonstrated for them. Neither of these two people are audiophiles and both said they heard the difference.

12) Correct: None of the techs have had the entire system on their bench at once, in any of its manifold configurations. At the moment the pieces that have been tested are the amp and preamp, only, not the CDP (whose power supply gets abnormally hot under routine operation), the BDP, the plasma TV, or the speakers (which were built for me by Jim Salk and arrived at the house brand-new).

Constants include the AC-line, the room, and the rack, yes, and very little else, since the entire system has been repeatedly re-cabled during this ordeal. In fact, even the presence or absence of after-market doodads like DIY low-pass filters on the speakers, RF filtration gadgets, and the power supply itself, have been switched into- and out of the rig with no noticeable effect.

The "other room test" is a great idea -- especially since I can use someone else who isn't any of these three friends and who happens, into the bargain, to be an audiologist.

I'd say I listen at "high-moderate" levels, shall we say, oh, 92db? (Just a guess.)

Will try what you've suggested. In the meantime, any further thoughts?

Zman9001
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Re: Back to ask again! (long! sorry!)

You dont live near any radio/ tv antennas do you? high voltage lines? industrial parks? shopping complexes? anything with strong magnetic fields in or near the house?
After reading your last post I still hold fast on my aforementioned advice with the addition of running all equipment from the same outlet/ circuit. Do any neighbors have similar problems with electronics in their house? Have you noticed erratic behavior with other components in the house? For example computer tend to act very fishy when they're getting what we in the biz call "dirty" power, although an excellent power supply can correct this in a computer.

I still think a highly capacitive/ inductive load in or near your house could have some bearing on how your system sounds. Why do you think so many people said in the last poll that their system sounds better at night?

JoeE SP9
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Re: Back to ask again! (long! sorry!)

I this problem has occurred and reoccurred in a selection of different components over a long period of time the gear is probably not the problem. I would look elsewhere.

Have you considered exorcism?

dog_or_man
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Re: Back to ask again! (long! sorry!)

I've just finished uploading eight images to a thumbnail gallery on a hosting site called imageshack, and will post the link to the thumbnail gallery here. The thumbnails are arranged in two rows of four.

Top row (L to R) :

1) My rig, in its latent state in a rack with no rear panel and front doors open

2) Points of conduit entry to the attic above the breaker (note the small white-painted copper tube, emanating from the wall, just below the elbow of the water pipe visible at right (more about this, below)

3) Electrician-friend's temporary solution to dedicated AC-line. He had two outlet boxes of two outlets each on his truck, so he overlapped the plates a little (background). Undedicated AC line is in foreground. At the moment the CDP, Amp, and Preamp are connected to the dedicated line, and the power supply (which manages the TV and BDP) is connected to the undedicated line

4) Sample of the "controlled chaos" at the back of the stack, including painstaking attempts to ensure that power cords, IC's, and speaker cables only cross at right angles. (Power wraps have no noticeable effect on problem, f-y-i).

Bottom row, (L to R) :

5) Inside breaker-box, made by "Square-D," c.1949. The un-dedicated line serving the home entertainment rig is bottom-left, single breaker

6) Close-up of break in that thin copper tube that emanates from the wall in picture 2, near that elbowed water pipe. I cut this thing with my hedge trimmer shortly after moving in to the house, and it is affixed to an external water spigot in such a way as to suggest that it's a grounding mechanism for something

7) Close-up of the thin copper tube's connection to the spigot, directly below the break -- is this a picture of some sort of grounding mechanism? Should I perhaps have avoided grabbing both severed ends of the thin copper tube, to take this picture? (Nothing happened, by the way)

8) Close-up of the outside breaker panel -- dedicated line is top-right, and it's a split breaker because electrician-friend didn't have a joint breaker on his truck (plans to replace).

pictures

Jan Vigne
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Re: Back to ask again! (long! sorry!)

I don't know if this can be solved on the forum but maybe a few more answers might lead to something.


Quote:
1) Every piece of equipment you have tried has resulted in the same problem? Or, in other words, no equipment change ever resolved the problem even momentarily/temporarily?


Quote:
1) New gear solves the problem temporarily. It usually takes longer, the first time there are new boxes in the stack, for the problem to recur. After that we're right back to the same "period" on the pendulum.

That doesn't make much sense if the problem exists in the system or anything inanimate associated with the system. Have you ever tried going back to a piece that you have replaced? In other words, after the problem shows up, it seems to stay. If you replace the component, it takes awhile for the problem to surface and then repeats itself on a regular schedue. At that point have you ever gone back to a component that was displaying the problem on a constant schedule?


Quote:

Quote:
2) The Parasound had a similar problem to the current system but also had the whooshing sound.


2) Yes -- similar in the sense that wiggling the appropriate interconnect on the rear apron caused the problem to dissipate and then not be repeatable until it recurred on its own.

So you do not need to break the connection? You just need to "wiggle" the ic plug? And this is the plug where in the system? Has it always been the same plug that you wiggle with each component change?


Quote:

Quote:
4) The onset of the current problem is immediate or gradual?


4) Onset of current problem is gradual after connections have been broken and reestablished. First recordings sound not quite their best, then not quite up to snuff, then not quite listenable, then terrible.

Twenty minutes or so won't get you through one CD. So this problem occurs within the course of a single disc? And I assume you've tried replacing the disc and going back to the beginning of the disc where it sounded OK. And in either case the sound problem remained? Only wiggling an ic jack solves the problem temporarily? What happens if you shut the system down for about ten minutes and then restart the listening session?


Quote:


Quote:
5) The problem only exists in the left channel? Only the left channel front and rear or only the left channel front? Or all channels?

5) With the Parasound gear it was only in the left channel, but now the problem seems to be in both channels, equally, though it's more difficult to verify because it's less easy to isolate sonically. Between the Parasound gear and now, incidentally, I also damaged two pairs of speakers at relatively moderate listening levels, both of them in the left channel only.

Now you've said something that really doesn't make sense to me, why is the sound problem not easily isolated? You can't tell whether the problem exists in one, both or all speakers? Why not? You turn the balance control to shut down one channel and listen, right? You place your ear close to one speaker at a time and listen for the problem, right? Why is the problem not easily isolated?

But even if the problem does exist in all the speakers, wiggling just one ic pluc solves the problem temporarily?

How did you damage the speakers, what problem appeared in the speakers? The same problem in both damaged speakers? I assume you had the speakers repaired or replaced, what did the technicians think might have caused the problem?


Quote:

Quote:
7) The system receives AC from two different locations, one a dedicated line and another a non-dedicated line with a power supply in line?

7) Correct, though that configuration is only the most recent of several that have been tried during all of this, and to that extent has been "ruled out" as a possible cause.

Have you ruled out the possibility that other equipment in the house might be the cause or at least contributing to this problem? Do you power up all the components when you listen? Even the TV when you are only listening to music? Does running the system in a smaller configuration have any effect on the problem?


Quote:

Quote:
11) Only the whooshing sound from the Parasound has been heard by others?

11) Not exactly. Others have heard the more recent unpleasantness, too, and the remedy was demonstrated for them. Neither of these two people are audiophiles and both said they heard the difference.

And were their opinions unsolicited or had you asked them if they heard a problem?


Quote:

Quote:
12) None of the techs have had the entire system on their bench at the same time? What pieces have been checked by a technician?

12) Correct: None of the techs have had the entire system on their bench at once, in any of its manifold configurations. At the moment the pieces that have been tested are the amp and preamp, only, not the CDP (whose power supply gets abnormally hot under routine operation), the BDP, the plasma TV, or the speakers (which were built for me by Jim Salk and arrived at the house brand-new

Have the techs offered any opinions on what might be causing your problems? You must be dealing with a retailer for all of this equipment, has anyone from the dealer been out to check the system in your home? Have they confirmed a problem exists in your home?

Strip the system down as I suggested and listen in another room. Report back.

dog_or_man
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Re: Back to ask again! (long! sorry!)

Just a quick bump to this thread -- with some new info to report:

1) The "stripped down" rig, consisting only of CDP, preamp, and power amp, connected on the same (dedicated) AC-line, evidenced the same problems as before.

2) My electrician-friend thinks grounding issues will be easier to check than dc-offset, which suggests he doesn't have the equipment to check the latter at his disposal.

3) The breaking-IC connections and re-establishing them turns out to be a red herring: It's the *POWER* connections that have to be disconnected and reestablished, only. I'd been disconnecting all the components from AC power in order to swap-out IC's, and the IC reconnections were getting the credit for the improvement.

4) The CD-player transformer doesn't just get extremely hot, it also has an audible hum which I'd never noticed before this most recent round of tests. So the amp and the CD-player are both humming from inside their respective chassis.

5) I installed Xitel ground loop isolators between the CDP, preamp, and power amp, with no improvement.

Follow-up thoughts are welcome and appreciated as always. Are we perhaps zero'ing in on DC-offset?

michiganjfrog
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Re: Back to ask again! (long! sorry!)

It seems the problem is you still haven't isolated the problem. Trying to fix the problem before knowing what is causing it, can be a monumental waste of time. Unless its ghosties, its going to be either a fault with your house wiring (ie. ground) or one of the components. As I seem to recall, you said the problem was still present at a friend's house across town. That would suggest a poorly grounded component, except you also said it happened with other components. If you really changed all components and location, the only thing to conclude there is somehow, the power company is causing everyone's system to produce strange noises. Except you're the only one complaining, so that can't be it.

If you haven't done so, you need to swap all components for different ones, until you find out which is producing the problem. Change the amp-preamp for a different amp, change the cd player, change the speakers.

If swapping all 3 components still doesn't isolate the problem, then you know its probably your house wiring. But in order to know whether its interacting with your equipment, you then have to take your equipment to another location with different wiring, if you want to be sure the fault is due to your house wiring. It could show up in any location if your equipment has a ground fault, but it is highly unlikely all 3 components produce the same fault. My stab in the dark guess is the amp-preamp is either causing or transmitting the problem (meaning it may be fine in another location).

mrlowry
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Re: Back to ask again! (long! sorry!)

Has the AC line's voltage been tested? As well as to make sure that the AC outlet isn't miswired (hot-neutral swap, etc)? Is this that same electrician that installed the dedicated line? If so it might be good to get a second pair of eyes and hands in there. It's always easier to find someone else's mistakes than one's own, not to mention admitting them.

JIMV
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Re: Back to ask again! (long! sorry!)


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The sound is perfect for the first twenty or thirty minutes -- always has been, and I always think I've fixed whatever's wrong -- and then, gradually, the sound becomes reedy and increasingly sibilant in the upper midrange and apparently "over-modulated" right around the midrange-tweeter crossover.

Is it possible that your turning the gear off, replacing gear etc, simply gives your audio memory time to dump its previous impression and it takes another 20 minutes in the new session to hear the same problems...???

If you hear the problem everywhere and with a lot of different gear, perhaps the problem is not in the gear but in the ear.

JIMV
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Re: Back to ask again! (long! sorry!)

You note that the problem is heard by others...Ok, is it heard by others before you direct them to it? Do they come out, without ANY input from you or foreknowledge of the problem, and remark on the sound?

If not, then the problem might need you to be heard by others..

JIMV
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Re: Back to ask again! (long! sorry!)


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Follow-up thoughts?

I know you have said you are broke, but perhaps borrowing a PS Audio power plant can answer this issue...it generates new clean power from scratch. If you have a power in problem perhaps using this can confirm it. If it solves the problem, PS Audio sells B stock units for way under list.

Jan Vigne
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Re: Back to ask again! (long! sorry!)

Give a few answer to these questions;

Have you ever tried going back to a piece that you have replaced? In other words, after the problem shows up, it seems to stay. If you replace the component, it takes awhile for the problem to surface and then repeats itself on a regular schedue. At that point have you ever gone back to a component that was displaying the problem on a constant schedule?

Why is the sound problem not easily isolated? You can't tell whether the problem exists in one, both or all speakers? Why not? You turn the balance control to shut down one channel and listen, right? You place your ear close to one speaker at a time and listen for the problem, right? Why is the problem not easily isolated?

How did you damage the speakers, what problem appeared in the speakers? The same problem in both damaged speakers? I assume you had the speakers repaired or replaced, what did the technicians think might have caused the problem?

Have you ruled out the possibility that other equipment in the house might be the cause or at least contributing to this problem? Do you power up all the components when you listen? Even the TV when you are only listening to music?

Have the techs offered any opinions on what might be causing your problems? You must be dealing with a retailer for all of this equipment, has anyone from the dealer been out to check the system in your home? Have they confirmed a problem exists in your home?

Buddha
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Re: Back to ask again! (long! sorry!)

Since replacing one item at a time and checking to see if the problem resolves/persists is out of the question for some reason, I'll just go with you having a bad cold solder joint somewhere. As your gear plays, it changes the temp of the joint and it starts to misbehave.

mrlowry
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Re: Back to ask again! (long! sorry!)


Quote:
Since replacing one item at a time and checking to see if the problem resolves/persists is out of the question for some reason, I'll just go with you having a bad cold solder joint somewhere. As your gear plays, it changes the temp of the joint and it starts to misbehave.

Yep, that would be a very good theory but I believe that he said that EVERY piece of gear/cable has been changed over time and that the problem remains. But cold solder can do some crazy things.

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