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#130182 02/20/06 10:41 PM
Joined: Sep 2003
Posts: 114
B
Member
I have a customer with tons of money to spend on his audio/video equipment. Thus far, he has nearly spent 1 million (this is not a joke). He has told me that an audio/video expert has told him he should rewire the power feed to his subpanel with a special high end wire. Currently, this subpanel feeds all his equipment. This will give "cleaner" AC power according to the expert. He didn't have any details as to what the wire was, he just knew it was 30k for a roll(125' ?).

Has anyone any experience with this sort of application or know if this special wire will actually give measurable results? I understand that low-voltage cable for the system between components is important as is surge protectors, but why would a better line to feed it be necessary? Where would you stop with this idea... re-feed the pull to the transformer at the street?

Your thoughts would be appreciated.

Byron

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#130183 02/21/06 12:01 AM
Joined: Apr 2004
Posts: 349
Member
Maybe we could get him better quality windings on the transformer too.

Seriously, I'm a sound mixer as a hobby, and I have received catalogs for high end audio equipment and cabling that price-wise makes pro-audio gear look like swapmeet junk by comparison. I'm talking amps, pre-amps, turntables & stuff that run $20K each and higher, and they sell very very expensive cable sets for the audio signal.

So what do you buy in spending $100K or so for a home stereo? Very very quiet. Pure signal with no noise. I can tell you that it wouldn't be very useful in my house! Way too much background noise.

IMHO, I think that's where the insanity should end, at the aduio signal. I would like to think that most audio equipment power supplies would provide whatever isolation is needed, especially at these prices, and that the line side would be relatively unimportant (within reason).

I would also imagine the video components would be far less important than the audio.

Radar


There are 10 types of people. Those who know binary, and those who don't.
#130184 02/21/06 12:50 AM
Joined: Nov 2005
Posts: 827
Likes: 1
J
Member
Sounds like hogwash to me. Snake oil salesmen of old have mostly been reincarnated as audio salesmen. For some folks though, half of their enjoyment comes from bragging about how much they have spent/(wasted?) on audio equipment. I try to ignore folks like these because I hear them talk about "Skin effect" or the sound that you get from a certain speaker wire, not referring to its gauge. Well, I used to maintain a 2MW UHF CH61 so we had hollow center conductors in our transmission lines because of skin effect. I just don't want to hear that mentioned at baseband audio though. Then there were all of those high end amps with the super specs for big $$$. They just sounded like garbage unless they had a few hours to warm up. The worst part is when they are owned by the folks who blast them because their ears are probably shot above 12kHz.

I think they should save their money and spend it on something practical like a Cessna Mustang, or a ride on a Virgin Airlines spaceship.

Just make sure he picks up his $30,000 / roll cable instead of expecting you to buy it for the job. And remember to charge him extra for the installation because you have to sprinkle it with half an ounce of pixie dust per foot for it to be effective.
Joe

#130185 02/21/06 05:28 AM
Joined: Mar 2005
Posts: 1,803
Member
Bragging. The late Kerry Packer, an inveterate gambler, once deflated a Texan Oil Man who bragged he was worth $60,000,000. He took a nickel out of his pocket and said
"Toss you for it!"


Wood work but can't!
#130186 02/21/06 06:44 PM
Joined: Sep 2005
Posts: 202
W
WFO Offline
Member
Quote:
"The worst part is when they are owned by the folks who blast them because their ears are probably shot above 12kHz."

Exactly!
Mine stop working about 10.6kHz; which is, oddly enough, the exact pitch of my wife's voice. [Linked Image]

#130187 02/21/06 09:06 PM
Joined: Mar 2004
Posts: 391
B
Member
My favorite is the audio equipment that advertises frequency response through something like 60kHz. Maybe this is so your german shepard can also enjoy everything your sound system has to offer. [Linked Image]

And I love the fact that they need all this gold-plated oxygen-free teflon-coated cable for their 20k audio signal, but any 100MHz oscilloscope probe is just gonna be a length of regular ol' coax with a steel BNC connector. In which application is signal integrity more important? [Linked Image]

-John

#130188 02/22/06 10:28 AM
Joined: Aug 2001
Posts: 7,520
P
Member
Snakeoil indeed, most of it.

O.K., you could argue some justification for getting clean power with as low a source impedance as possible. If the equipment is running from a tatty old 100' 18-gauge extension cord in a loose receptacle which on the end of a undersized branch circuit which has a bad ground and fridges and A/C compressors clicking on and off, you might get some noise problems.
But beyond a sensible approach of using suitably sized cable, good connections, etc. it just gets silly. If the system already has its own dedicated sub-panel and properly sized conductors, throwing away money on nonsense like $300/ft. cable isn't going to do anything.

Remember those $150-ish "Audio grade" receptacles from a while back? I haven't heard about the PoCo's building "audio grade" power plants yet, nor "audio grade" transmission lines.

#130189 02/22/06 02:58 PM
Joined: May 2005
Posts: 984
Likes: 1
G
Member
It's not just the audio folks who are confused. I had a sound consultant when I was working on a theater who insisted that I twist the conductors feeding a 200A panel. Other than being virtually impossible to pull, it was also dumb. He finally told me the reason that he wanted the feeder twisted.
It was to reduce the noise in the theater. He knew that twisting the wires in a data cable reduced the noise and figured that twisting the power wires would do the same thing. I guess he figured that 'noise' only had 1 meaning.
It was just my profound professionalism that helped me hold my laughter until AFTER the meeting.


Ghost307
#130190 02/27/06 10:28 PM
Joined: Nov 2005
Posts: 827
Likes: 1
J
Member
Let's face it, they could spend 30K on wire that won't gain them anything and botch the whole job by not using good grounding techniques that cost them next to nothing.
Joe


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