Up Grade Power Cord ???????? - Page 10 - AVS Forum
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post #271 of 419 Old 04-27-2013, 03:12 PM
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Silly argument. I believe the contention of the people who use upgraded power products (cords, conditioners, etc.) is to isolate the gear from all of the crap on the "wires connecting the house to the power transformer on the pole".

Even sillier. You can't isolate a conductor that's firmly and electrically bonded to another conductor...it would be counter productive.
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post #272 of 419 Old 04-27-2013, 03:21 PM
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Originally Posted by SAM64 View Post

Even sillier. You can't isolate a conductor that's firmly and electrically bonded to another conductor...it would be counter productive.

Reading comprehension is in obvious short supply here. That is NOT what I said.

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post #273 of 419 Old 04-27-2013, 03:37 PM
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And exactly how does a power cord isolate anything?That is exactly what your said Rutgar!
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post #274 of 419 Old 04-28-2013, 05:47 PM
 
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Originally Posted by Just cruising View Post

And exactly how does a power cord isolate anything?That is exactly what your said Rutgar!
I see no problem with what they stated here "I believe the contention of the people who use upgraded power products (cords, conditioners, etc.) is to isolate the gear from all of the crap on the "wires connecting the house to the power transformer on the pole"."

Yes, there are some that believe that using cords like this http://www.b-p-t.com/cables.html or even this one http://www.ultraaudio.com/equipment/isoclean_superfocus_80a3_pt3030g_ii.htm

I like Rutgar find that some on here have a difficulty in understanding people, let alone show that they have poor comprehension skills, when it comes to stuff that people can prove fact over what some show as fiction.
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post #275 of 419 Old 04-28-2013, 07:01 PM
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I see no problem with what they stated here

That doesn't surprise me at all.
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I like Rutgar find that some on here have a difficulty in understanding people, let alone show that they have poor comprehension skills,

lol
That's mighty rich coming from you.
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post #276 of 419 Old 04-28-2013, 07:56 PM
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Well the problem is that a power cord provides connectivity to the power distribution system in your house not isolation!
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post #277 of 419 Old 04-29-2013, 03:56 AM
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Perhaps they're not comprehending the meaning of the word 'connectivity' .
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post #278 of 419 Old 04-29-2013, 04:50 AM
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Which might explain why so many people will fall for this type of snake oil…they don't understand 2 words that have opposite meanings.
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post #279 of 419 Old 04-29-2013, 05:48 AM
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Originally Posted by Gizmologist View Post

JN it amazes me that a man with your technical background (which you delight in the extreme in demonstrating to us mere mortals) is wholly unable to grasp the concept the most of us who live in the real world and deal with practical events and system designs and BUDGETS have been doing so quite successfully.

I have yet to see you publish a peer reviewed example of taking a building with any type of pro grade AV equipment and run all the usual performance tests prior to being granted unlimited license to gut the building's electrical and mechanical systems and redesign and install them to YOUR specs and then re run the performance tests for a before/after item by item comparison.

Question: If the performance of the various systems meets the spec of the manufacturer, the desire and expectations of the client and does so reliably for the lifetime of the system components, why are you so anal about saying (figuratively) "yea but, yea, but , there are ground currents that are out of control and we must tame them!"?

Seriously JN, no one really cares about fields that the systems and the people involved suffer NO ILL EFFECT from. We all admit they DO exist, BUT if they cause no harm in a given system, give it a rest.

Have you had ANYONE who installs this equipment professionally come to you and say "JN. until we rebuilt the entire building grounding structure and replaced all the conduit runs etc we just couldn't solve our AV problems but now after spending 50 milion dollars, our 100 thousand dollar system works.... just the same as it did before"?

BTW JN, AV contractors have known and exercised numerous construction techniques for decades to eliminate hum, ground loops etc from the cable lays to mechanical isolation etc. That is why we have all made a nice comfortable living.

You really should accept that PRACTICALITY is a major influence in the purchasing and installation of AV equipment for most companies and individuals.

Wow...again with diversionarly tactics.

I have a novel idea. How about technical talk. I note that you haven't...You have done nothing but denigration.

It is unfortunate you have built a name for yourself here based solely on trashing those who you do not agree with..

Now, to respond to your only viable statement..
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Originally Posted by Gizmologist View Post

Question: If the performance of the various systems meets the spec of the manufacturer,

STOP RIGHT THERE....

What specification? How many pieces of pro or consumer equipment out there are tested to meet ground loop current rejection from 20 hz to 20 Khz?

Answer: NONE


Reason: There is no specification, no test methodology, nothing.

Why:

People like you..

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post #280 of 419 Old 04-29-2013, 08:05 AM
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Originally Posted by Gizmologist View Post

why are you so anal about saying (figuratively) "yea but, yea, but , there are ground currents that are out of control and we must tame them!"?

Why do you even ask that question??

The AV professionals out there who DESIGN the pro equipment you use acknowledge that there are ground currents out there, and that they ABSOLUTELY DO impact the operation of PRO BALANCED equipment. You acknowledge that you actually build into your quotes the cost of additional isolating transformers because your experience has been that DESPITE the use of balanced pro equipment, you still have grounding problems.

If you sell your services based entirely on mcgvering solutions in heroic efforts to save the day, then I can understand why you keep arguing as you've done here.

The problems being addressed now within the AES on ground loop issues are in the PRO arena, where they already go to great effort to reduce susceptibility.

What about consumer audio?? Most of it is NOT balanced, it's still rca unbalanced.. That is where the ground currents can also impact the quality of the sound.
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Originally Posted by Gizmologist View Post

Seriously JN, no one really cares about fields that the systems and the people involved suffer NO ILL EFFECT from. We all admit they DO exist, BUT if they cause no harm in a given system, give it a rest.
Your talking to the wrong person. Tell it to Bill Whitlock, tell it the the AES guys who are addressing it..

I honestly do not know why you said ""people involved suffer no ill effect from"". Was that a typo?

In the meantime, I recommend you discontinue your failed attempts at trying to convince everybody that a problem the pro world is currently wrestling to resolve doesn't exist, is "minutia", or that it cannot exist in the consumer world. It's there, it exists, it's being worked on by guns bigger than you and me... you've missed the bus.

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post #281 of 419 Old 04-29-2013, 08:29 AM
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Whatever floats your boat JN. I have yet to see anyone here in the pro AV world jump on your bandwagon. As I and EVERYONE else in the pro AV world knows, various issues can present and also can be dealt with PRACTICALLY, on a budget and quite successfully. Simple as that.

I suppose you hope I am offended my your repeated attempts at insults or belittling me by your ad nauseum referrals to "McGyvering". News flash Scoote!, I have made a very nice career as have thousands of other AV pros making systems work. If the client is happy and the system works, what specifically what is the down side of using a transformer to solve a problem, especially when the customer was not inclined to experiment by hiring YOU to completely rebuild his building and spend hundrecds of thousands to millions of dollars, depending in the burilding size and complexity? I asked this question of you before and you ignored it.

Which of us will stand a better chance of landing a AV system contract and be able to build a system on budget and on schedule in an existing building.

BTW here is another little piece of trivia for you. RARELY are buildings built around an AV system. The are generally considered "outfittings".

But you go ahead and beat your horse until there is no flesh left.
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post #282 of 419 Old 04-29-2013, 09:19 AM
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Originally Posted by Gizmologist View Post

Whatever floats your boat JN. I have yet to see anyone here in the pro AV world jump on your bandwagon.

So you can badger and attack them as well? Your bullying tactics are quite well known, especially when you take a stance which has no engineering merit.
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Originally Posted by Gizmologist View Post

As I and EVERYONE else in the pro AV world knows, various issues can present and also can be dealt with PRACTICALLY, on a budget and quite successfully. Simple as that.
So then what you really need to do is go to the AES meetings where these issues and concerns and solutions are being discussed by the PRO arena big guns, climb up on stage, and yell at the top of your lungs why the technical discusion they are having is, ""minutia"".
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Originally Posted by Gizmologist View Post

I suppose you hope I am offended my your repeated attempts at insults or belittling me by your ad nauseum referrals to "McGyvering".
It's simply the category you fall into. I come across your type of engineering all the time. Do the quick and easy things as fast as possible, and then when problems arise, come across as heros by saving the day.

Good engineers will stop to consider what the root cause is, then attack that. You are happy to run around with a fire extinguisher on you back, others prevent the fires from starting.

If you are happy being an engineer who doesn't look at the overall problem, that's fine.

But don't claim it doesn't exist. So many others disagree with you.

Ah sheesh, here's the strawman argument again..
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Originally Posted by Gizmologist View Post

News flash Scoote!, I have made a very nice career as have thousands of other AV pros making systems work. If the client is happy and the system works, what specifically what is the down side of using a transformer to solve a problem, especially when the customer was not inclined to experiment by hiring YOU to completely rebuild his building and spend hundrecds of thousands to millions of dollars, depending in the burilding size and complexity? I asked this question of you before and you ignored it.
I've never said that. Give it up, everybody knows better.
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Which of us will stand a better chance of landing a AV system contract and be able to build a system on budget and on schedule in an existing building.
The funny thing? My work will make yours easier, despite your protestations.

Oops...strawman alert:
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Originally Posted by Gizmologist View Post

BTW here is another little piece of trivia for you. RARELY are buildings built around an AV system. The are generally considered "outfittings".
Nobody said that..

Here's another attempt at winning the argument without any technical content:.
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Originally Posted by Gizmologist View Post

But you go ahead and beat your horse until there is no flesh left.

Sigh...

The argument you choose to rail upon is over Giz. It started being over in 2012 when Bill Whitlock included work on ground loop causes and mitigation, it started when he included the statement that pin 1 problems are ALSO build into sources..it started when he began injecting 60 hz half sine into pin 1 to troubleshoot PRO equipment.

You are yelling at the sun in an attempt to keep it from setting.

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post #283 of 419 Old 04-29-2013, 09:40 AM
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I think the biggest misconception here is that I condone the use of high priced power cables and interconnects as solutions to system "sound" problems.

I do not.

The root cause of the problem is the design of the equipment.

Pro equipment is susceptible to the pin 1 problem because, while they use balanced differential, they do not control all the currents which flow into or out of a piece of equipment. This is a prime tenet of EMC, or Electro-Magnetic Compatibility theory and practice.

Consumer equipment is far worse off when they use RCA type unbalanced interconnections. This has also led to the class of products which fix ground loop caused problems by breaking the ground path, in direct conflict with the safety desire of grounded enclosures.

The fixing of high end consumer equipment for this problem will probably be years behind the pro arena (my guess).

It is my sincere hope that once the consumer equipment had been designed to better EMC standards, there will no longer be a need for fancy PC's or IC's (edit: or ANY aftermarket cords other than those for ampacity or connecter quality concerns). Until such time, are we, as forum participants, supposed to accept and allow the browbeating and bullying given anyone who states that their system was altered by cordage? Obviously, that is not my world.

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post #284 of 419 Old 04-29-2013, 09:45 AM
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Originally Posted by Nyal Mellor View Post

Plenty of examples where it is difficult to correlate measurements to subjective effects...jitter being a good one it seems. Witness the debate at the birth of computer audio...how can all these computer playback methods sound different even though they are bit perfect. There were a good few years when no one understood what was going on until people figured out maybe jitter was at the root of it.


I haz a sad reading this. I used to think you were a credible source of information. Hopefully you still are, as regards acoustics.
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post #285 of 419 Old 04-29-2013, 10:02 AM
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Originally Posted by Nyal Mellor View Post

I have no issues with what you say, and I'm not saying any of these 'audiophool' theories are true, but it's worth bearing in mind that to many people the standards bodies and universities act to maintain the status quo - see Thomas Kuhn http://en.wikipedia.org/wiki/The_Structure_of_Scientific_Revolutions.

oh for pete's sake.... you're bringing in Kuhn now?

To many people Kuhn's 1962 book is an oversimplified model of complex and varied processes. His model of scientific revolutions doesn't fit as well to my field (biology) as it does to pre-1962 physics, for example. And many others have weighed in :
http://en.wikipedia.org/wiki/The_Structure_of_Scientific_Revolutions#Criticisms


Speaking of models, yes, let's always bear in mind that 'scientific knowledge' consists of models that are in a constant state of refinement ('all models are wrong, but some are useful') -- but that doesn't mean that an audiophool theory and the current model should be considered equally likely to be false.
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post #286 of 419 Old 04-29-2013, 10:18 AM
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Sorry. But I would not consider Monster Cable 'High End'.

It's not at all important that you do. It's only important that the Average Consumer with a vague yen to 'upgrade' , instilled in them by a salesman while buying a TV, AVR, CDP, loudspeaker set at Best Buy, believes that Monster Cables are affordable 'high end' and 'sound better' than stock.

But they don't. And neither do boutique cables. The latter are just more of a ripoff than even Monster, albeit with less market clout.
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post #287 of 419 Old 04-29-2013, 10:22 AM
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I don't consider myself a "zealot," but my two systems are all over my personal web site. Below is a photo of my living room HT setup. Many of the pros who post in this forum also have web sites showing their gear and rooms.

--Ethan

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for heaven's sake Ethan, surely you can afford more elegant speaker stands than those? wink.gif
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post #288 of 419 Old 04-29-2013, 10:34 AM
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Audibility is a different story. I do not make claims either way. I have experienced it of course, but that is specific to my cords, my system, and me. It cannot simply be applied elsewhere.

Audibility *is* the story. But here you go again, down the rabbit hole.
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post #289 of 419 Old 04-29-2013, 10:38 AM
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for heaven's sake Ethan, surely you can afford more elegant speaker stands than those? wink.gif

LOL, those $12 Walmart step stools work perfectly, and are the exact height needed once I added the cardboard box and plywood / riser. I still have a pair of beautiful custom hand-made oiled walnut stands a friend made for me. He's a professional cabinet maker, and even though he's a friend they were still expensive. But they're all wrong for my current Mackie 624 speakers. So yeah, I am a cheap bastid, and proud of it. biggrin.gif

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post #290 of 419 Old 04-29-2013, 10:42 AM
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What about consumer audio?? Most of it is NOT balanced, it's still rca unbalanced.. That is where the ground currents can also impact the quality of the sound.
One time my subwoofer was humming which distracted the enjoyment of music. It stopped when I plugged to different power receptacle. Been fine ever since. smile.gif
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post #291 of 419 Old 04-29-2013, 11:45 AM
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Based on reading Bill Whitlock's papers some years ago I now tie all my Pin 1 directly to the chassis right at the connector when building a piece of gear. Never on a cable or breakout panel, here I keep pin 1 isolated. It makes perfect sense in that the shield should be only an extension of the chassis and nothing more. When it's drawn out you can plainly see it. The worst thing you can do is to run the shield back to the circuit signal ground (in a balanced interface of course). Yes, it eventually ties to it at some point in the product but the whole idea is preventing a loop.

Where a lot of pro gear get's into trouble is with PC board mounted connectors. Unless you have a separate chassis ground trace you can't abide by the above. As a lot of pro gear is manufactured to low cost for the club band market, corners like this are cut. From my experience a lot of so called audio "pro" gear is built in China using the same mass production consumer techniques. It's the only way you can sell a 16 input "pro" mixer for $400.

Inclusion of rack ears and XLR connectors does not make a device "pro grade" anymore. It used to years ago but not anymore. Then we have the pro audio stuff that uses an XLR or stereo phone connector yet ties it to an unbalanced circuit. They just ground the ring or pin3 inside the chassis for you! I have DBX bass equalizer that does just that!

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post #292 of 419 Old 04-29-2013, 12:03 PM
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Originally Posted by jneutron View Post

The fixing of high end consumer equipment for this problem will probably be years behind the pro arena (my guess).

It is my sincere hope that once the consumer equipment had been designed to better EMC standards.....

Isn't it true though that this increased interest in consumer EMC issues is due to RFI problems rather than fixing audio hum problems? Of course it's the same medium that causes both but as just about every audio product today has a DSP and Microprocessor running over 20mhz, the RFI leakage through the interconnects and power cord is the major EMC problem and that is federally regulated in most countries.

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post #293 of 419 Old 04-29-2013, 12:15 PM
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Isn't it true though that this increased interest in consumer EMC issues is due to RFI problems rather than fixing audio hum problems? Of course it's the same medium that causes both but as just about every audio product today has a DSP and Microprocessor running over 20mhz, the RFI leakage through the interconnects and power cord is the major EMC problem and that is federally regulated in most countries.

Ah..I have to be more specific. There is indeed the rfi problem and the feds do set standards for output and susceptibility, I'm not speaking about that.

I'm speaking only about the stuff like high end gear and onesy/twosey type stuff where somebody spends waaay too much money, then finds the equipment is sensitive to cordage..

Then they become prey to the aftermarket vendors who promise "fixes" with weird things that have no physical meaning..

Did you read Whitlocks indy AES 2012 paper regarding balanced power? What do you think? I'm not well versed in that, so couldn't critique the content.

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post #294 of 419 Old 04-29-2013, 12:30 PM
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Many years ago Shure pro products used to isolate the input cable shields and audio path ground from the chassis ground by using a 51 ohm resistor in series with a .1 ceramic disc cap. many manufactures folllw a similar path today.

The only recent issues I have had with RF incursion was in an installation in north carolina that was in a senior center about a 1/4 miles from an AM radio station. The installation company had used quality plenum grade foil shield lines for all the mic runs but the station signal was a clear as though is was a direct input to the system. I "McGyvered " the problem quite successfully by changing out all the single paired, foil shield cables with Canare L4E6S quadstar cable. (Not plenum grade but it is what I had available) with no load on the input and the input level at 50% there was ZERO RF incursion. Change back to the old cable and voila! radio.

The second was a Children's Hospital in Norfolk, VA. (King's Daughters). Quite a varied system install with several generations of adds and modifications, satellite feeds, multi room ties and feeds, multiple medium playback and recording. A steady low level hum in the system was loud enough to be distracting. After living with it for a few years and after 3 other companies failed to eliminate it, I was called by the building facilities manager. I inserted ONE of my little trouble solving transformers a just the right point and total silence. No more hum. The auditorium works nicely, the owners and BoD are happy, I got paid and all is well.

Down side for anyone?
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post #295 of 419 Old 04-29-2013, 12:44 PM
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Originally Posted by Gizmologist View Post

The only recent issues I have had with RF incursion was in an installation in north carolina that was in a senior center about a 1/4 miles from an AM radio station. The installation company had used quality plenum grade foil shield lines for all the mic runs but the station signal was a clear as though is was a direct input to the system. I "McGyvered " the problem quite successfully by changing out all the single paired, foil shield cables with Canare L4E6S quadstar cable. (Not plenum grade but it is what I had available) with no load on the input and the input level at 50% there was ZERO RF incursion. Change back to the old cable and voila! radio.

I recall Whitlock does talk about the drain wire causing problems because the loop current goes all asymmetrical. Was the wire you pulled the type with foil and drain?
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Originally Posted by Gizmologist View Post

The second was a Children's Hospital in Norfolk, VA. (King's Daughters). Quite a varied system install with several generations of adds and modifications, satellite feeds, multi room ties and feeds, multiple medium playback and recording. A steady low level hum in the system was loud enough to be distracting. After living with it for a few years and after 3 other companies failed to eliminate it, I was called by the building facilities manager. I inserted ONE of my little trouble solving transformers a just the right point and total silence. No more hum. The auditorium works nicely, the owners and BoD are happy, I got paid and all is well.

Down side for anyone?

Well, yah. They had to pay somebody to come all the way from SoCal to Va to install a silly little transformer. Course, you coulda just told em what to do over the phone..

Upside? Yah, you were paid for a service call from the other side of the country, when all it needed was a simple little transformer..

If the system had no ground loop hum sensitivity, you'da never made that money. I can certainly see why you balk at fixing the root cause..

jn

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post #296 of 419 Old 04-29-2013, 12:46 PM
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Originally Posted by Gizmologist View Post

Many years ago Shure pro products used to isolate the input cable shields and audio path ground from the chassis ground by using a 51 ohm resistor in series with a .1 ceramic disc cap. many manufactures folllw a similar path today.

The only recent issues I have had with RF incursion was in an installation in north carolina that was in a senior center about a 1/4 miles from an AM radio station. The installation company had used quality plenum grade foil shield lines for all the mic runs but the station signal was a clear as though is was a direct input to the system. I "McGyvered " the problem quite successfully by changing out all the single paired, foil shield cables with Canare L4E6S quadstar cable. (Not plenum grade but it is what I had available) with no load on the input and the input level at 50% there was ZERO RF incursion. Change back to the old cable and voila! radio.

Down side for anyone?

Full power AM stations in close proximity can wreak havoc on baseband audio and video systems. But consider this, many radio and TV transmitter facilities are grouped or clustered in a close geographical area, like within a few hundred feet of each other, so they have to be very careful with systems engineering in their plants. There is much engineering material dating back 50 or more years on proper grounding techniques at RF facilities and they do work. It's all about what else - grounding! And that doesn't mean just throwing ground rods in all over the place. That would only make it worse in most cases. It's the engineering of the total system that makes it work. I agree some of the techniques learned here are overkill for AV systems but the root electrical engineering is the same for both and parts of it can be applied to AV systems.

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post #297 of 419 Old 04-29-2013, 01:36 PM
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I had a complete physical last week. My doctor apparently needed to make a yacht payment, the all-inclusive package included a stress-echo test. There was little else to do but fret about my chest being shaved, so while waiting I inspected the power cords going into all of this ultra - sensitive healthcare equipment. Now I will admit that aesthetics may be less important in the fields of cardiology and radiology, and behind those plain black wrappers there may have been 6' of $500 copper, but the leashes that tethered this equipment to the wall appeared no different than those which power my computer, my printer, my AVR or amplifier.

Someone should notify the healthcare industry of the same phenomenal breakthrough currently afforded the gullible in audio. Lives could be saved.

Medical equipment is designed so that there are no leakage currents or ground loop currents at the inputs. Two things could happen. First, ground loop currents are within the bandwidth of the low level signals they are looking at. Second, leakage currents to ground through the patient are for some reason, frowned upon..

Consumer audio equip? No such regulation, no such design.

You present a strawman argument. It has nothing to do with the topic at hand.

jn

ps..my apologies for the quips earlier.

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post #298 of 419 Old 04-29-2013, 04:16 PM
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for heaven's sake Ethan, surely you can afford more elegant speaker stands than those? wink.gif

His wife just needs to dress them up with some nice covering and it would be just great. wink.gifbiggrin.gif
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post #299 of 419 Old 04-29-2013, 05:20 PM
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First as I mentioned, the wire I used to replace the foil and drain wire cable was Canare L4E6S, a quadstar lay with a very tight braided shield. I have used this quite successfully for everything from data lines to communications, all levels of audio (no, not speaker level) lighting control with great success. This cables is among the most popular with professionals as it is so well built that it can be laid around and on top of a rat's nest of lighting cables with dimmers running at 50% (a rather electrically noisy realm) and remain silent and impervious to noise incursion.

Second, the trip to NC was NOT made to install a transformer. I was on vacation and took a side trip north to the hospital at their request.. Obviously, there would be no way to diagnose a problem over the phone.

I fail to see why you just cannot grasp the concept of resolving an audio issue within a limited time frame and budget. Do you really believe anyone is going to pay for your deegree of on-site measurements and experimentation when someone like me can pop in, listen to the problem, isolate the location and install a system fix that completely eliminates the issue and for a very reasonable price.

What would the facilities manager say to the BoD as far as the cost of YOUR analysis and experimentation vs my solution to the problem? There is a small issue called "Return on Investment" that most companies are rather concerned about. Perhaps you have heard the term.
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post #300 of 419 Old 04-29-2013, 06:33 PM
 
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Quote:
I see no problem with what they stated here

That doesn't surprise me at all.
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I like Rutgar find that some on here have a difficulty in understanding people, let alone show that they have poor comprehension skills,

lol
That's mighty rich coming from you.
Do you understand what the term "Blocked user" is? Do you realize that I have you blocked, so that I do not have to see the crap you spew out belittling others, like myself and those you seem to think are under you.

I am not the only one btw that has you on their block list, so maybe instead of responding to those like me, find some other hobby to do on this forum.

Sorry Sam, but as far as I am concerned, you do not exist, because of remarks as I quoted in this message. So as a police officer during a accident scene states to gawkers, "Move along, nothing to see here.".

I also suggest that you forget that I even exist on this forum, because as I have already stated, you are blocked for a reason, and this little jackass comment you made, gives even more reason why people ignore you.
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