GoodSoundClub - Romy the Cat's Audio Site - Isolation of turntable motors

08-02-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1826
Post ID:	26846
Reply to:	26845

"Optimized for Audio"

The way I understand it, power line "regenerators"/noise scrubbers pretty much have to be optimized for a specific load/application, and "off-the-shelf" units are compromized, by comparison. Who actually "optimizes UPS/power scrubbers for audio"? Sure, the sellers SAY their products are audio-centric; but I am not at all convinced of this, or what it really means, anyway, and that includes the Pure Power. Of course, if something "works", then it works. And I'll settle for that every time, back stories nothwithstanding.

Paul S

08-08-2022

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Amir
Iran Tehran
Posts 347
Joined on 02-11-2009

Post #:	1829
Post ID:	26850
Reply to:	26849

High Power UPS in Market

If i am not mistaken It seems Most High Power UPS in the market like APC or ABB are not good for high dynamic loads (high crest factor like Music signal) and the load transient response of these UPS is not very good at rated power. APC , ABB and ... are designed for IT/Server/Computer rooms not for music systems.Yes i know the subject is complex but I can guess the first step is going for fast load transient response of UPS.

111.68.99.22:8080/xmlui/bitstream/handle/123456789/4897/10%20Muhammad%20Aamir%20Conference%20Paper%20Review%20Uninterruptible%20Power%20Supply%20%28UPS%29%20system.pdf?sequence=1&isAllowed=y

deadbeat control for UPS

The deadbeat controller is an attractive control solution for many applications where the fast transient response is required.

The control strategy is the most important part of all UPS systems. Parameters like THD of the output voltage, dynamic response to the transients and spikes; power factor correction, voltage and current regulation etc. are all dependent on the con- trol strategy applied in the UPS system. Nowadays many modern control techniques have been proposed to provide regulated out- put voltage in all the circumstances. Broadly the control techni- ques can be classified as single control and multi loop control schemes

Pure power 3000 is a successful model for under 800w load and i think If Richard (purepower) improve purepower in both "power" and "transient response" then I can use it for my high power class ab system.

www.amiraudio.com, www.hifi.ir

08-08-2022

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rowuk

Germany
Posts 454
Joined on 07-05-2012

Post #:	1830
Post ID:	26851
Reply to:	26850

Load transient response?

I think that the load transient response is 100% in the device power supply - not passed on to the grid. If the amplifier power supply is not properly dimensioned, a UPS could change the sound, but only because of the amplifier deficiency. It would make more sense to solve the problem instead of using a workaround.

In my opinion, the manufacturers of audio devices need to fix the problems in the devices. They certainly are asking for enough money for our expectations to be demanding proper operation in "normal" living conditions.

Whenever I feel blue, I start breathing again.

08-08-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1831
Post ID:	26852
Reply to:	26851

Weight, along with "other factors"

Robin, it would indeed be nice if "audio component manufacturers" made and sold gear that delivered consistently good sound when used "in the real world". Not to let anyone off the hook, but many (if not most) audio "manufacturers" buy, market and re-sell finished (or mostly-finished) assemblies (or even the entire compontents) from "jobbers", who might or might not accomodate "unusual" ideas from re-sellers. And something not to be overlooked in any sort of manufacturing is weight. Shipping large batteries, transformers, cases, etc. only works economically for specialty manufacturers. Not to mention the popular notion that one regenerator will serve all the gear in a "typical" audio system. If you believe that, you only need one regenerator to put things aright. Now, what's to stop me from continuing on about using more than one regenerator in a system?

Paul S

08-09-2022

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rowuk

Germany
Posts 454
Joined on 07-05-2012

Post #:	1832
Post ID:	26853
Reply to:	26852

New can of worms

Let us suppose that one manufacturer figures out what the grid is doing and how to solve it - in his own amps/preamps/DAC. Does that help us? Only if we happen to like their products...
As the "high end" market is truly sick, the solution is always to throw (a lot) more money at the issue - without even knowing what he core problem is. The words "transients", digititis, or even "regenerator" are freely used without regard to what is happening.
In my world, a "high end" amplifier has an "excessive" power supply to cover any operating condition without ever running out of steam. In this case the effects of the grid are "additive" - they can pollute if the power supply cannot filter.
I think that there may be something else. The most reports of negative grid effects seem to be from 110V/120V grid fraction - not from Europe with 220-240V.

Whenever I feel blue, I start breathing again.

08-09-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1833
Post ID:	26854
Reply to:	26853

Parts and Wholes; Limits and Options

Agree that it seems more people complain about grid power in US. Also agree that a "good" power supply is just that. Still, it seems like a good idea to have a good power supply as part of a "good" amp (or, whatever...). Some of the "best" amps I have heard were/are "good within limits", like my old Wright Sound 2A3. Lamm ML2s "extended the limits". My current Marantz MA9-S2s "extended on those limits". No, they do not do "everything better" than the ML2s. If wishes were fishes...

Paul S

08-10-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1834
Post ID:	26856
Reply to:	26728

DIY

I know Romy is skeptical of DIYers who want to do everything as cheaply as they can but there are others who do things themselves since they are not satisfied with what the market provides.
I can think of one loudspeaker system, in particular, that defines the best of DIY.
I have never been interested in regenerators since I have convinced myself I have unobtrusive AC plus I had other parts of my system that needed attention first.
I noticed a breathless post in AUDIO ASYLUM (I take a quick look every three months or so) and see that Ric Schultz who is known for being out of breath more often than not is experimenting with DC to AC inverters and giant sized LiFePo batteries.
I have long found Schultz to be an interesting fellow. I was surprised, but not shocked, when Clark Johnsen had nice things to say about him. He thought his hearing was much better than average and trusted his sonic judgements.
Schultz and a friend are experimenting with a DC to AC inverter rated at "5000 watts" - available at AMAZON for just under one thousand dollars in conjunction with two 200Ah batteries in parallel - he was using LiFePo but I think I would consider using SLA STGM batteries at about half the cost but more than twice the weight. Not as if I will be moving them about.
Link to inverter - https://www.amazon.com/dp/B08XXBVW35/ref=twister_B09H263X7F?_encoding=UTF8&th=1
One can assume the 5000 watts spec is advertising. The user reviews at AMAZON are very confusing since they have more reviews of cheaper models overwhelming the few for the 5000 watts model.
Nowhere is there an example of the output waveform. Distortion is listed as equal to or less than 3 percent.
As usual no one has ever heard of the company that makes this thing. It is a rather substantial 26 pounds.
One would think 400Ah of battery is far more than the PUREPOWER possesses. One would also tend to think that inverter technology has matured and has reached the point of not much further returns are possible so this could easily far surpass the PUREPOWER's inverter if not be its equal.
One part of me wants to give this a try. But I would like to hear what those of you who have been thinking about this for years think.
Take care,
I put spaces between paragraphs - oh, well ...

08-11-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1835
Post ID:	26857
Reply to:	26856

Power vs. Waveform vs. Sound

Rick, as I "remmember", the PP output waveform was a "perfect" squarewave, in terms of shape, but it's pulsed. And I think Romy said it worked with a load of up to 60% of "capacity". Does a different regenerator have to "work the same" to "sound as good"? Could it work differently and still be acceptable? This seems like a classic case where one will simply have to try it in order to find out how it works/sounds in one's own system. I also like the idea of a big, tough battery, which I suspect would be the first place a "manufacturer" would cut corners. For what it's worth, I have told here that my friend's giant Tesla UPS system, with 2 Tesla batteries, sounds better when the grid is connected. Not sure what this "proves"; but it's kept me from adding a large UPS, dispite his electricity sounds better than mine no matter how his UPS is configured. It should also be noted that his phased, unbroken, dedicated circuits sounded way better than my electricity even before he installed his UPS.

Paul S

08-11-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1836
Post ID:	26858
Reply to:	26857

More wandering in the AC forest

Thanks for your thoughts.
What is the TESLA battery? You mean the monster thing they use in the cars? Now that would be one hell of a battery!
If I do it i will get SLA SGMs - gigantic LiFePo makes me nervous - I try to stay as far away as I can from TESLAs when I encounter them on the road.
Of course, you are right - until you try something all else is speculation - so I probably will give it a try. My curiosity has the best of me.
The PP outputting a square wave - now that takes me by surprise.
I do not doubt the AC quality that plagues Romy is very real but I have had my suspicions that the PP imprints its own sound - like a garden variety 300B amplifier; makes everything sound the same. Reading that the output is a pulsed square wave, as if I have any idea of what that would look like, gives me some hope this thing might do something good.
One way or another i will let you know what I think I hear.
Take care

08-11-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1837
Post ID:	26859
Reply to:	26858

Batteries as Supplies and Buffer

Not sure if the big Tesla Powerwall batteries are Li (I suppose they are), but the best battery I've actually tried is a big dry cell, best because it can (apparently) survive and continue to function indefinitely just sitting there for months on end, while SLAs I've tried have fairly limited lives in this use. My drycell is an Odyssey. The 'scope pics of a PP output are somewhere in this thread; rather, they were. The pulse seems to indicate the converter is a switcher. Plenty of speculation, you'll recall, that the switching was/is at least part of "the umami effect" the PP provides. Anyway , the PP does not put out "a perfect sinewave".

Paul S

08-14-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1839
Post ID:	26861
Reply to:	26860

How to Charge and Keep Charged

Rick, that's a whole lotta battery you're employing! So far, I've gotten the idea you want to run your hi-if system with batteries only via a DC to AC converter, and no AC to DC, meaning, you don't want your system connected to the wall at all. Is this correct?

Just out of curiosity, I googled the price of Powerwall batteries: $11,500 for 1. Big price break, $18,500 for 2. There are "cheaper" dry cell options at 200Ah, but they are still shockingly expensive.

Paul S

08-15-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1840
Post ID:	26864
Reply to:	26861

It works

That's much more than I am able to spend!
All of the stuff came in yesterday so I spent an arduous day having to rewire my system.
I had been using a 2000VA isolation transformer for each channel. All that was connected to the two transformers are now powered by the inverter.
The inverter is larger than I imagined it would be. The batteries are heavy and bulky as one would expect of SGM batteries.
Got it working about eight o'clock. The first few minutes were dedicated to IT WORKS. Then I tried to relax and listen for the things I was worried it might do - like limit dynamics. This is not the case. There is a greater sense of front to back spaciousness. Cymbals and bells sound more like metal and less like compressed air. Not that this was revelatory. The system did respectably before.
It will take much more listening to favorite records to get the full measure of the thing.
The power meter shows it is producing 640 watts at 120 volts. There is a flicker of plus minus 1 volts AC voltage. I thought the power usage was going to be much more than that. I guess it is loafing along. The case got warm but the fan never turned on.
I do not hear any funny noises either from the inverter or from my speakers.
So far I think it is a success. Much more time needed to be sure.

08-16-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1842
Post ID:	26866
Reply to:	26865

I would suspect it is a switcher

Isn't everything these days?
I do not hear any extraneous noises coming from the box or through the speakers.
Here is a link to the device I bought: https://www.amazon.com/dp/B08XXBVW35/ref=twister_B09H263X7F?_encoding=UTF8&th=1It says nothing about what is inside. The box is far more imposing that the photograph would suggest.
I had to move my speakers to get to the isolation transformers and last night discovered I had not put them back in the exact same place. Oncve3 this was settled I did find that the setup is better than I had thought.
The fellow who recommended this set up spoke of installing a separate ground rod just for the inverter - as it is I have it grounded to the house system. I would think this would make one even more immune to the vagaries of the grid.
I am tempted to give this a try since it does make sense,
I would never have installed a separate ground rod if the system was connected to the line but this seems safe and probably the finalizing of the divorce from the grid.
So far, no regrets at all and I do believe i am enjoying listening to music more.
Thanks for your thoughts and encouragement
I wish I knew how one imposes spacing between paragraphs here. I place spaces but they disappear when posted.

08-16-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1843
Post ID:	26867
Reply to:	26866

Dedicated Ground (again...)

Rick, as I have chronicled at GSC, I have used a dedicated ground for my phono for many years. The Ticket seems to be to keep amp ground wires lifted, and in your case you would connect just the inverter ground wire to the dedicated ground line, and the inverter neutral wire would still go to the house service ground bus. I recommend a bare copper 12 AWG wire, and either clamp it very tightly, or (my preference) solder it to the copper ground rod (use a torch). If necessary, you can use small isolators to stand the wire off surfaces it crosses on the way to the rod.

Impose PP spacing by hitting "Enter" 3 times, rather than 2X.

Paul S

08-16-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1844
Post ID:	26868
Reply to:	26867

More ground

Thanks for the spacing tip.

At this point the only part of the inverter attached to the house is through the ground - and that is using a plug for just the ground lead into a close-by receptacle.

My main amplifiers (tri-amplified system) are utilizing only hot and neutral - the rest of the system does have the ground wires connected.

So with the addition of the ground rod there will be nothing connected to any part of the house's electrical system.

The system is absolutely silent - no noises are heard with one's head inside the horn.

Will be interesting to hear if there are noises you do not realize are there, until they are gone, eliminated with the ground rod.

Did you install your audio ground rod yourself or have someone do it?

An interesting aside - when the battery is at full charge (13 to 14 volts) the output voltage is lower than when the battery nears 12 volts and I do think I am hearing better sound with the battery in the 11.8 to 12.2 volts range. So much imagination is possible with a new something in the mix.
Take care, Paul

08-16-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1845
Post ID:	26870
Reply to:	26868

The DIY Version

Rick, I have been in building/construction for most of my life, and very comfortable installing the ground rod and lead-out wire, etc. Easy-peasy, if you ask me. You can drive the rod using a ladder and a demo hammer that is big enough to fit the top of the rod in lieu of a typical bit. If you rent such a tool, there are actually attachments that are made for driving ground rods.

Silent power is good! But there may well be some "inaudible noise" that "rides" the house ground, and the pulsed inverters are said to be particularly "dirty". You won't know what will happen until you play with it for a while. I would not be without my "bleeder".

Not sure at all about the battery sounding "best when not fully charged", but I think I remember that many batteries are "modeled" at 80%, whatever that means.

Paul S

08-17-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1846
Post ID:	26871
Reply to:	26870

I agree

No question there is noise bleeding in from the rest of house - I just don't know it yet. When something is taken away I can miss it but am not the most perceptive before being made aware of what to listen for.

John Broskie talks about us being broken in along with new components. I do wonder about that. I am enjoying music more the more I listen to this thing. Of course, something new in the system always makes the system more interesting while one is trying to decide whether it is better or not. I will know much more about the value of this in a few weeks when the possibility of sonic errors become more annoying from familiarity.

I have an electrician who has done work at my house so I contacted him to do the rod installation. I am a diy'er but thought that might be something I cannot do. This is Georgia and the soil in substantially red clay. Not to mention lots of rocks so i am going to be lazy.

Do you think the copper coated rod is sufficient for this? I see there are pure copper rods available which would seem the perfect fit for the obsessed kook audiophile. I hope for this duty the standard copper coat will be plenty good enough. I suspect it will outlive me.

There is a company in Angleland making a filter for a dedicated ground. The fellow who brought this idea to my attention seems to thing this device made by a company called PURITAN is something to consider. I could see it having some usefulness when more than one component is connected to the grounding system but with only the inverter I cannot imagine a device no matter how clever doing anything. So there will be a simply substantial wire from the inverter to the rod.

Still seems like the system sounds best with he battery slightly run down. Took it down to 11.5 volts last night and it continued sounding very good.

I monitor my playback with the RTA part of REW. The only anomaly I see is around 22kHz. A spike of about 30 dB. Needless to say I cannot detect it with my ears. What is strange is this same spike would occur at times with the old setup. At this point I am not certain it is from the inverter.

I am not one who leaves the system playing music even when i am not listening seriously. This approach is likely not for those who want to listen for long periods. With a full charge I think one can expect four hours - which is plenty for me. One can turn on the charger and go on for any length of time - I do this when making adjustments but have not listened to it with the charger connected. There is no doubt there is a penalty not to mention the noise form the charger's fan.

I love music too much to listen to it all day long. I remember Romy writing about listening to one piece of music that was so satisfying that was enough for the day.

Take care, Paul

08-17-2022

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Paul S
San Diego, California, USA
Posts 2,657
Joined on 10-12-2006

Post #:	1847
Post ID:	26872
Reply to:	26871

Lower Resistance

I don't know about the Puritan "ground filter", or what sort of own problems it might introduce along with purported benefits, but the main idea of the dedicated ground is to have the lowest resistance possible, and no measurable noise. I believe my own ground rod is copper with a steel core, because that drives better than all copper.

30 dB spike at 22k Hz? Might be from a switcher. Got any dimmers?

Paul S

08-18-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1848
Post ID:	26873
Reply to:	26872

I am skeptical and in agreement

Seems to me if one goes to the trouble of having a single ground point in the ground and there is but one ground point on the inverter and all is plugged into the inverter who needs an interloper? Schultz is reporting about the system of a friend who, lucky for him, seems to have a close to unlimited budget which does tend to tempt one into believing all sorts of wonderful claims. As opposed to cheap Scots like myself who find every reason they can to say NONSENSE.

As with all of this stuff one never knows until they try. So I will never know!

I had not thought about the dimmer and I do believe the light with the dimmer has been on at all times. I should have suspected that and greatly appreciate you mentioning the possibility of the dimmer.

One never knows what goes on inside our brains but the system has been keeping me entertained and relaxed more than it did. As I have said before - if I can say this a month from now I will know the inverter is doing something good.

Take care, Paul

08-18-2022

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rickmcinnis
Posts 60
Joined on 10-18-2010

Post #:	1850
Post ID:	26875
Reply to:	26874

Not using a super tweeter

I am using the Celestion Axi-periodic compression driver in the KLIPSCH K402 horn which I have boosted considerably when I noticed that the top one and one-half octaves were barely working when playing music so I figured WHY NOT? and it works just fine. Distortion measure high at approx. 19 KHz (1.5% thd) at a level one would NEVEr encounter listening to anything one would want to listen to. I use a xilica Solara DSP which I would have scoffed at a few years ago and now I cannot live without it. PEQ has come a long way and whatever compromises it imposes are more than made up by advantages from a smoother frquency response which in turn gives a smoother phase response..

There is a dip just before 20kHz but then there is a rise - when measuring with REW - so it is entirely possible this noise is being "heard" by the microphone. But I am only sweeping from 20Hz to 20Khz.

You can be sure when i get home this afternoon I will measure with the light on and off.

I will need to ask REW to measure to 24kHz - I usually have it stop at 20 - so i have not noticed it before when taking measurements.

But my instincts are that you are right about the source - and better still, I hope you are right!

PS I posted about the inverter at DIYAudio since i spend a fair amount of time there at the PASS Forum - I must admit I posted it just to hear the typical DIYAudio experts tell me how stupid the idea was. One fellow, who I actually like, made the inane comment of using the batteries to power my amplifiers which require 70 volts of B+ and another told me I needed to add LC sections to my power supply filters. I love LC filters in the power supply but know all too well that too much of a good thing is not always very good but then I am not omniscient like the omnipresent DIYAudio naysayers. It is like, instead of listening to their music systems they stare at the computer screen all day waiting to tell someone how their idea won't work with no intention of ever trying it for themselves and most assuredly having never tried it It is fascinating.

A fellow who goes by the moniker of PRR, who is a genuine expert on electrical stuff, gave me pause about the need for the ground rod; it may well be superfluous. He said I should try removing the ground from the inverter to the "house" and to hear what happens. It turns out the fellow who first posted about this is also trying this. Makes sense to me. But then i will know better tomorrow after I have tried it.

Hope the proprietor is not annoyed by my posting about this!

Thanks, Paul, and take care,

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