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Old 5th March 2011, 08:52 PM   #10621
hhoyt is offline hhoyt  United States
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Default Signal dependent noise

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Originally Posted by Steve Eddy View Post
Yeah, but in both of those instances, I don't see that a signal is required. The noise should be there with or without signal...
You are of course correct, the interfering signal is always there. In the case of the RF pickup, rarely the actual interference only becomes audible when in-band signal intermodulates against it, creating an in-band product. This type of signal dependent noise is most often found the facilities with co-located RF plants, but I have heard it on some hifi tuners as well. Audibly it reminds me of scrape modulation in magnetic recording.

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Old 5th March 2011, 09:09 PM   #10622
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Quote:
Originally Posted by jacco vermeulen View Post
Mr Weedy-B,

'cough', you do realise that still leaves 2 options.

(of which i gathered neither is a safe bet)
When we went to the Netherlands Antillies we received several warnings that what was ok in Amsterdam was not ok here. I still think I should have dropped a bar of Valrhona Cannabis Chocolate in my carry on and pleaded ignorance.
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Last edited by scott wurcer; 5th March 2011 at 09:20 PM.
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Old 5th March 2011, 09:43 PM   #10623
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Quote:
Originally Posted by Steve Eddy View Post
Yeah. But I'd like to know just what the mechanism is that would cause it.

se
Say your circuit is quiet @ 1mA(idle) but @ 5mA(idle) noisy.
With a signal that causes 5mA the circuit does not
differentuate between signal current and idle current.
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Old 5th March 2011, 10:48 PM   #10624
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Quote:
Originally Posted by scott wurcer View Post
I still find it interesting that you think your style of listening might have commercial potential.
The emphesis should be on the word might. One factor is that there is no standardization of recordings or of system performance. The expectation that you can somehow filter out the listening room is IMO hopeless. Therefore no recording sounds the same on any two systems and most recordings have one or more serious FR errors on any one system because of the variables inherent from one recording to the next even on the same label.

The technology I have developed requires among other things standardization to work. These variables become magnified and make matters even worse than they already are if they aren't corrected. Standardization of performance, now there's a novel idea in this industry all by itself.
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Old 5th March 2011, 11:10 PM   #10625
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Quote:
Originally Posted by Soundminded View Post
The emphesis should be on the word might. One factor is that there is no standardization of recordings or of system performance. The expectation that you can somehow filter out the listening room is IMO hopeless. Therefore no recording sounds the same on any two systems and most recordings have one or more serious FR errors on any one system because of the variables inherent from one recording to the next even on the same label.

The technology I have developed requires among other things standardization to work. These variables become magnified and make matters even worse than they already are if they aren't corrected. Standardization of performance, now there's a novel idea in this industry all by itself.
The protocol you describe would seem to some incredibly time consuming even tedious. Trained experts to custom set up your listening space to the way it “is supposed to sound”. I think you have gone back around to the Bose customers except they are peeling a few more C notes off their stash.
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Last edited by scott wurcer; 5th March 2011 at 11:30 PM.
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Old 5th March 2011, 11:54 PM   #10626
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Quote:
Originally Posted by scott wurcer View Post
Antillies not ok.
Yeah, even Campo Alegre at Curacao isn't what it used to be in the good old days.
(still, i recall a 2nd engineer of a Nedlloyd ship who, till this very day, will deny to ever have been in close contact with a transformer job in Thailand)

Even Steve seems to have trouble keeping track of the right number.
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Old 6th March 2011, 12:18 AM   #10627
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Quote:
Originally Posted by scott wurcer View Post
The protocol you describe would seem to some incredibly time consuming even tedious. Trained experts to custom set up your listening space to the way it “is supposed to sound”. I think you have gone back around to the Bose customers except they are peeling a few more C notes off their stash.
You have it backwards. A sound system which is adjusted to accomodate itself to the acoustics of the room it is installed in to achieve uniformly predicatable results. A real novelty in this industry. Not only new technology and standardization but a rare innovation. Actual engineering.
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Old 6th March 2011, 01:09 AM   #10628
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Quote:
Originally Posted by Soundminded View Post
You have it backwards. A sound system which is adjusted to accomodate itself to the acoustics of the room it is installed in to achieve uniformly predicatable results. A real novelty in this industry. Not only new technology and standardization but a rare innovation. Actual engineering.
Believe it or not standardization does not appeal to all in every endeavor. Call out the Handicapper General.
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Old 6th March 2011, 01:47 AM   #10629
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For everyone else, we made perhaps 45 units, of which 40 were sold to outsiders. We had only 2 major problems: Both overseas. The first major problem was when Bob forgot to put some isolated machine screws that tightly mounted the TO-220 fets. They were held by pressure and thermal grease, however, one of the elbow isolating washers broke lose started rattling around. Bob took a chance with the customer in Singapore, that he had a 'qualified technician' who could put the machine screws in, without the necessity of sending the unit back to the USA. However, the tech FORGOT the isolating elbow washer, and attached one of the power supplies live to the chassis.
I personally had to pay for the airfare (about $1100) to and from Singapore as well as airport costs, each way. The unit came back a second time, this time from input stage damage, probably due to lightning. I paid one way, return, perhaps another $600, the second time, because the guy's wife refused to compensate me. They lost their Warranty over this.
Another customer had this super turn-on transient, which blew up 2 power amps and both channels of the CTC in 3 separate incidents. We had to return the money in full for the two amps ($5,000) and had to add a ZENER protection for the input stages of the CTC. Hopefully he sold it to someone else, as I have not heard from him, recently. He's yours, Joachim in future. '-)
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Old 6th March 2011, 02:01 AM   #10630
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J.J. contacted me. You know the privat banker. Seriously, if i can help i do.
His unit is fine. He is just afraid about the "obsolete Fets". I do not know what kinds you put in there but i have a big stock of 2SK170, 2SJ74 and others.
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