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#58575 - 11/12/05 05:20 PM Sound studio
HCE727 Offline
Member

Registered: 11/11/05
Posts: 190
Loc: Delaware County, PA, USA
I wired a small residential sound studio, which is being expanded. The GC (All GC's know everything about everthing but know nothing about anything) is telling me that the homeowner is getting feed back from the electrical system? the only thing that I can think of that is causing it is dimmers that I installed. Anybody have any experience with studio's?
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#58576 - 11/12/05 05:41 PM Re: Sound studio
SolarPowered Offline
Member

Registered: 07/05/04
Posts: 615
Loc: Palo Alto, CA, USA
I'm trying to picture how you could possibly get feedback through the electrical system. It would seem that something in the electrical system would have to be microphonic, and cause enough disruption in the power feed that it gets through the filtration in a power supply, and back into the audio signal. I've never heard of such a thing in an electical power system.

Can you describe a bit more what the symptoms are?

[This message has been edited by SolarPowered (edited 11-12-2005).]

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#58577 - 11/12/05 05:44 PM Re: Sound studio
HCE727 Offline
Member

Registered: 11/11/05
Posts: 190
Loc: Delaware County, PA, USA
The GC just told me "feedback", I think that I am going to bypass him and talk to the homeowner.
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#58578 - 11/12/05 06:02 PM Re: Sound studio
Sixer Offline
Member

Registered: 08/08/05
Posts: 264
Loc: Canada
Wonder if he means it's a "hum"? I recently had a customer complain to me about a hum coming from their sound system - they use the rec room for band practise. My thoughts too were the dimmers. Also the owner has put compact fluorescents all throughout the house, so I suggested he try turning off anything with dimmers and compact fluorescents when they practise. I still haven't heard back from him, so I'm assuming that was the problem.
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#58579 - 11/12/05 06:05 PM Re: Sound studio
HCE727 Offline
Member

Registered: 11/11/05
Posts: 190
Loc: Delaware County, PA, USA
The only problem with turning off all the dimmers, is that the dimmers control all the lighting in the studio.
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#58580 - 11/12/05 06:34 PM Re: Sound studio
classicsat Offline
Member

Registered: 11/23/02
Posts: 449
Install resistive or autotransformer dimmers.

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#58581 - 11/12/05 06:36 PM Re: Sound studio
HCE727 Offline
Member

Registered: 11/11/05
Posts: 190
Loc: Delaware County, PA, USA
Would that do the trick, does Lutron carry those?
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Hank

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#58582 - 11/12/05 06:55 PM Re: Sound studio
HCE727 Offline
Member

Registered: 11/11/05
Posts: 190
Loc: Delaware County, PA, USA
I just talked to Lutron, the only thing that they have is a Lamp Debuzzing Coil, which will stop some buzzing but not all. Lutron said the same thing, resistive or auto transformers, which will cut out all of the buzzing. Are thera any sites that I can check out? Thanks Classicsat!
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#58583 - 11/12/05 07:11 PM Re: Sound studio
e57 Offline
Member

Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
Feedback-Hum... Hmmm... Sound studio....
3-wire circuits, and/or 2-wire circuits of seperate phases will do this too, if equipent is connected/re-connected on the audio side.

Most of the audio guys I used to work for would request 2-wire circuits of both or all 3 phases available at all points, if not only one phase available for equipment. Then they could choose whatever phase sounded best to them. I never heard the difference!

Feedback-Hiss... Hisss... Sound studio....
Electronic noise induced on circuit, could be from anything. Dimmers, LV, or flouresant lighting, electronic amps, TV in the neighbors house - anything. All of the amplifiers could just amplify the radio signals emitted from them. Thats a shielding problem in thier equipment, not yours.

They could also have grounding issues in thier equipment as well. Which could cause both.... I have installed many isolated grounds for dedicated circuits. And on one occassion a "Common refferance ground" which amounted to a #2 back to the main with a ground bar that they could attach jumpers to form different equipment. Also never heard the difference....
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Mark Heller
"Well - I oughta....." -Jackie Gleason

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#58584 - 11/12/05 07:18 PM Re: Sound studio
HCE727 Offline
Member

Registered: 11/11/05
Posts: 190
Loc: Delaware County, PA, USA
Ah, your killin' me, before I get all worked up, I think that I am going to talk to the homeowner to see exactly what the problem is. Thanks E
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Hank

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