KeithL
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Post by KeithL on Jun 4, 2019 14:28:27 GMT -5
UPS units vary considerably in the amount of noise that they block or create. Some types only connect to replace the main power when it fails...
But others remain partly in-circuit at all times... And, as someone mentioned, there is the possibility that the battery charging circuitry itself will generate some line noise.
The problem is that most UPS devices were designed to provide uninterrupted power to computers...
And, to be quite blunt, computers simply aren't that fussy about a little bit of noise on their power lines, as long as the power isn't totally interrupted, and the noise level remains below a certain level. Therefore, with a UPS designed for computers, producing a perfectly clean and quiet line simply isn't a design priority.
(And, if you look at devices intended for super-critical applications, like medical equipment, they can be very expensive, due to other considerations that don't apply to audio gear.)
BTW my experience trying many forms of power to power my equipment my experience with UPS systems was the worst for sound quality. While I do use a very good UPS system with my desktop computer, I found that using a UPS in my sound system to be the worst and very poorly affected the sound quality. This poor sound quality was in normal use, under normal full power and not while the power was out putting the UPS into use, from my experience I would never use a UPS with my sound system. The only reason to have a UPS is for protection for computers to protect against information being lost by unexpected power loss as well as to protect things like a projector which may need cooling fans to run to protect against over heating and sudden power loss could cause problems with them not being able to cool properly. The only way for that to happen is for the UPS to be injecting noise (maybe coupled or radiated from the battery charging circuit, adding a ground loop, or other issue. Sounds like a defective (or just badly designed) UPS. I've never had that problem in the decades I've used them. In my case our local power is not terribly reliable, subject to brief (second or two) as well as longer (a week or so in a blizzard a couple of years ago) outages. A UPS means it rides out the short glitches without cycling everything on and off rapidly, the type of thing that can kill components, and gives me time for an orderly shutdown if it goes on for long. It also keeps my network alive so I don't have to wait for everything to reboot if power blips for a second or three. |
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Post by donh50 on Jun 4, 2019 14:50:48 GMT -5
UPS units vary considerably in the amount of noise that they block or create. Some types only connect to replace the main power when it fails...
But others remain partly in-circuit at all times... And, as someone mentioned, there is the possibility that the battery charging circuitry itself will generate some line noise.
The problem is that most UPS devices were designed to provide uninterrupted power to computers...
And, to be quite blunt, computers simply aren't that fussy about a little bit of noise on their power lines, as long as the power isn't totally interrupted, and the noise level remains below a certain level. Therefore, with a UPS designed for computers, producing a perfectly clean and quiet line simply isn't a design priority.
(And, if you look at devices intended for super-critical applications, like medical equipment, they can be very expensive, due to other considerations that don't apply to audio gear.)
The only way for that to happen is for the UPS to be injecting noise (maybe coupled or radiated from the battery charging circuit, adding a ground loop, or other issue. Sounds like a defective (or just badly designed) UPS. I've never had that problem in the decades I've used them. In my case our local power is not terribly reliable, subject to brief (second or two) as well as longer (a week or so in a blizzard a couple of years ago) outages. A UPS means it rides out the short glitches without cycling everything on and off rapidly, the type of thing that can kill components, and gives me time for an orderly shutdown if it goes on for long. It also keeps my network alive so I don't have to wait for everything to reboot if power blips for a second or three. The problems I have seen with off-line UPS units is mainly the battery charging circuit radiating and inducing noise in the components attached to it, and in some cases not attached (RFI over the air). The more expensive products like APC's SmartUPS and various other commercial "true" sine wave devices do produce a cleaner output but still not good enough for highly-sensitive equipment. That said, we do use them on our test equipment (things like high-end DSOs and RF analyzers, scary playing with things that cost more than my house!) There is a lot of isolation in most decent power supplies. Things like medical equipment use either standard UPS-type units with lots of filtering, or implement true high-power oscillators to provide clean sine waves. I do not mean to dismiss the concerns of UPS noise causing problems even when the unit is not on-line. IME, that occurs either due to a bad UPS or bad component -- "bad" meaning defective or poorly-designed; the latter can be true at any price point. I am curious how large a problem this is. Have others also had noise problems with UPS when off-line? I have not, or rarely, and not with the past few UPS units that have rolled through my audio system. I am wondering if I got lucky, or the other poster very unlucky, in our choice of UPS and other components. |
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KeithL
Administrator
Posts: 10,261
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Post by KeithL on Jun 4, 2019 15:04:17 GMT -5
You may be too young to remember how this sort of thing was done in the bad old days....
I've actually seen "power conditioners" from long ago that worked by using a high-current transformer with a two or three volt secondary... They would then switch that voltage into series with the line, in or out of phase, using mechanical relays, when they needed to "add or subtract a few volts to maintain the proper line voltage". Back then, there were also UPS units that put out nearly a pure square wave, or a "sine wave" with only a few steps, which worked just fine with incandescent lights and big old motors.
(Remember when cheap light dimmers put out variable-duty-cycle DC - chopped by an SCR - before they even bothered to use triacs?)
It would be nice to think that sort of thing has long gone to the scrap yard....
Of course, if you don't actually have trouble with dropouts, you can just forego the battery and generation stuff and stick with a noise filter and surge suppressor. (They're a lot cheaper and you don't have to replace the battery  .)
UPS units vary considerably in the amount of noise that they block or create. Some types only connect to replace the main power when it fails...
But others remain partly in-circuit at all times... And, as someone mentioned, there is the possibility that the battery charging circuitry itself will generate some line noise.
The problem is that most UPS devices were designed to provide uninterrupted power to computers...
And, to be quite blunt, computers simply aren't that fussy about a little bit of noise on their power lines, as long as the power isn't totally interrupted, and the noise level remains below a certain level. Therefore, with a UPS designed for computers, producing a perfectly clean and quiet line simply isn't a design priority.
(And, if you look at devices intended for super-critical applications, like medical equipment, they can be very expensive, due to other considerations that don't apply to audio gear.)
The problems I have seen with off-line UPS units is mainly the battery charging circuit radiating and inducing noise in the components attached to it, and in some cases not attached (RFI over the air). The more expensive products like APC's SmartUPS and various other commercial "true" sine wave devices do produce a cleaner output but still not good enough for highly-sensitive equipment. That said, we do use them on our test equipment (things like high-end DSOs and RF analyzers, scary playing with things that cost more than my house!) There is a lot of isolation in most decent power supplies. Things like medical equipment use either standard UPS-type units with lots of filtering, or implement true high-power oscillators to provide clean sine waves. I do not mean to dismiss the concerns of UPS noise causing problems even when the unit is not on-line. IME, that occurs either due to a bad UPS or bad component -- "bad" meaning defective or poorly-designed; the latter can be true at any price point. I am curious how large a problem this is. Have others also had noise problems with UPS when off-line? I have not, or rarely, and not with the past few UPS units that have rolled through my audio system. I am wondering if I got lucky, or the other poster very unlucky, in our choice of UPS and other components. |
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Post by donh50 on Jun 4, 2019 15:14:12 GMT -5
You may be too young to remember how this sort of thing was done in the bad old days.... I've actually seen "power conditioners" from long ago that worked by using a high-current transformer with a two or three volt secondary... They would then switch that voltage into series with the line, in or out of phase, using mechanical relays, when they needed to "add or subtract a few volts to maintain the proper line voltage". Back then, there were also UPS units that put out nearly a pure square wave, or a "sine wave" with only a few steps, which worked just fine with incandescent lights and big old motors.
(Remember when cheap light dimmers put out variable-duty-cycle DC - chopped by an SCR - before they even bothered to use triacs?)
It would be nice to think that sort of thing has long gone to the scrap yard....
Of course, if you don't actually have trouble with dropouts, you can just forego the battery and generation stuff and stick with a noise filter and surge suppressor. (They're a lot cheaper and you don't have to replace the battery .)
I'm almost 60, and actually have one of those stepped-tap transformer units. Somewhere in the black hole masquerading as our storage shed/workshop. But I have not seen one in decades; like you, thought they were long gone, replaced by the electronic versions. Could still be out there, I suppose. They would handle brown-outs and over-voltage conditions but were not actual UPS units, at least not the one I have. Once they switched the output was clean -- no switching supplies, just a relay, control circuitry, and the multi-tap transformer. Mine also served as an isolation transformer (not all would). There were also the SOLA transformers (those are still available). Edit: DC offset on the wall outlet is fairly rare but a real problem when it happens. Toroidal transformers are widely used in audio gear since their local EM field is much more confined than from a standard (EI) transformer (so less chance of inducing hum in the component), but their construction makes it difficult if not impractical to add an air gap, and without the gap that EI transformers have they are much more susceptible to DC-induced core saturation. |
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Post by Bonzo on Jun 4, 2019 16:53:45 GMT -5
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Post by audiosyndrome on Jun 4, 2019 18:20:12 GMT -5
I agree with some of the comments mentioned above. For instance, the power supply of a well designed piece of equipment should prevent any noise on the line from being relevant. But in my opinion AC conditioners and AC distribution units are a fundemental requirement for any good system because grounding is key to a lifelike noise free system. Plugging all of you system components into one conditioner or distribution unit goes a long way towards providing single point grounding and there in lies the key. Units plugged in here and there MAY have small differences in ground potential and those differences simply become part of the signal being passed through the system.
Plugging all or most (explained later) of your equipment into one box doesn't guarantee single point grounding but it's a good start. Not all conditioners and distribution units are created equal. Optimally, each outlet should be returned to the same single point (chassis lug) in the box. That ensures that all the units plugged in see the same ground potential. I think (?) the CM-6 is wired that way. All of my equipment, except the five amps, are plugged into a PS Audo Dectet which is wired properly as described. The Dectet is plugged into one of my two 20A dedicated lines as are all the amps, three into one line, two and the Dectet into the second line. So all my babies see the same ground potential.
My system is dead quiet, ear to the tweeter, nothing playing, because I've paid strict attention to single point grounding. I learned this many years ago as a video design engineer (the first 34 years of my career, audio the last 13 years). An alert four year old could tell whether or not one of my displays, cameras, scan converters, etc., used proper grounding techniques. And that's the truth.
Russ
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Post by audiosyndrome on Jun 4, 2019 18:36:47 GMT -5
Hello All, Who uses power conditioners for their systems, and what types are recommended? These things seem to be really expensive. I'm looking for one but not sure which one to buy. And I don't want to spend $1000 on one. Save your change and don’t buy one at all! A waste of money 💰 Bill Horses for courses! An audiophile buddy of mine lives in NYC in a 22 story building with 10 apartments to each floor. That may result in an enormous amount of air conditioners, microwave ovens, hair dryers, vacuum cleaners, etc., being used some (or God forbid) all of the time. My opinion, a good AC line conditioner or distribution unit would be of great benefit in his high end system. Horses for courses! Russ |
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Post by 405x5 on Jun 4, 2019 18:58:29 GMT -5
Save your change and don’t buy one at all! A waste of money 💰 Bill Horses for courses! An audiophile buddy of mine lives in NYC in a 22 story building with 10 apartments to each floor. That may result in an enormous amount of air conditioners, microwave ovens, hair dryers, vacuum cleaners, etc., being used some (or God forbid) all of the time. My opinion, a good AC line conditioner or distribution unit would be of great benefit in his high end system. Horses for courses! Russ It may indeed, but those Manhattan buildings are powered by very capable, commercial 3 phase services that handle the load and are really not comparable to a singular residential service between 100/200 amps. The real issue with this stuff is that too often, the thinking is reversed..... You start with...…..IS there any problem with my electrical service; and voltage fluctuations, ground loops, etc. should first be addressed by a licensed, electrical contractor. A competent evaluation could easily cost less then some of the prices I hear tossed around for power conditioners. By the way, this is different from UPS and surge protection, both of which I'm a fan for sure. Bill |
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Post by audiosyndrome on Jun 5, 2019 8:40:19 GMT -5
Bill- my second post was tongue in check but you missed it. Note that I underlined my opinion. You forgot to say in your post “a total waste of money” was only your opinion.
Russ
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Post by audiosyndrome on Jun 5, 2019 9:31:53 GMT -5
Horses for courses! An audiophile buddy of mine lives in NYC in a 22 story building with 10 apartments to each floor. That may result in an enormous amount of air conditioners, microwave ovens, hair dryers, vacuum cleaners, etc., being used some (or God forbid) all of the time. My opinion, a good AC line conditioner or distribution unit would be of great benefit in his high end system. Horses for courses! Russ It may indeed, but those Manhattan buildings are powered by very capable, commercial 3 phase services that handle the load and are really not comparable to a singular residential service between 100/200 amps. The real issue with this stuff is that too often, the thinking is reversed..... You start with...…..IS there any problem with my electrical service; and voltage fluctuations, ground loops, etc. should first be addressed by a licensed, electrical contractor. A competent evaluation could easily cost less then some of the prices I hear tossed around for power conditioners. By the way, this is different from UPS and surge protection, both of which I'm a fan for sure. Bill 200 amp service upgrade installed this last Saturday. Old 100 amp panel had no remaining spots and used Pushmatic breakers. The new panel is primary grounded via a 30 foot cable and clamp to the cold water main where it enters the basement. The secondary ground is just outside the garage via a 6-foot copper rod driven into the ground. $2,150 including whole house surge protection. Russ  |
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Post by 405x5 on Jun 5, 2019 10:53:41 GMT -5
"my second post was tongue in check but you missed it. Note that I underlined my opinion. You forgot to say in your post “a total waste of money” was only your opinion." Not a chance......I didn't miss or forget. Even the term "conditioner" is so non technical and boy the snake oil salesmen love that word! |
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Post by franky on Jun 5, 2019 11:51:03 GMT -5
Thanks Keith, I will check them out.
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Post by dxtrem3fx on Jun 5, 2019 12:22:57 GMT -5
Wow,
A lot of great information to take into consideration. I appreciate all of the input from everyone.
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Post by RichGuy on Jun 5, 2019 21:12:55 GMT -5
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Post by RichGuy on Jun 5, 2019 23:25:53 GMT -5
I also love my UPS it has saved me many times allowing me to save my work and shut down my computer. As a webmaster and website designer this is very important to me. But my home theater has no need for a noisy UPS and my desktop has no need for a power conditioner, they serve very different purposes.
My Belkin F6C1500-TW-RK 1500VA UPS with my desktop
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Post by tropicallutefisk on Jun 6, 2019 5:41:03 GMT -5
It appears the Belkin PF60 is no longer available. Is this correct? If so, did they replace it with something similar?
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Post by audiosyndrome on Jun 6, 2019 7:08:33 GMT -5
Yes. Discontinued several years ago without a replacement. MY PF-60 sits st the bottom of my son’s equipment rack. Hmmm; I wonder if he’d notice if it was missing. 😉
Russ
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Post by pedrocols on Jun 6, 2019 11:33:21 GMT -5
We should limit engineers' post to 50 words.
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Post by SteveH on Jun 6, 2019 16:41:01 GMT -5
Save your change and don’t buy one at all! A waste of money 💰 Bill I agree with Bill. I wired six dedicated 20 amp circuits for all of my audio gear. I am not going to choke my 20 amp circuits with 15 amp conditioners, I do use one CX-6 as a power strip for my RMC-1 and the low power consumption components. All of the amplifiers and sub woofers can run full throttle on their own personal 20 amp circuits. |
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Post by dxtrem3fx on Jun 6, 2019 17:12:19 GMT -5
Yeah, I'll be saving my money and just purchasing a CMX-6 for now. I like the idea of dedicated 20 amp circuits. My friend is an electrical contractor.
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