Using a UPS for power conditioning

Double conversion UPS are AC regenerators like the Power Plant, so why not save money and use one of those instead of a more expensive device from PS Audio? Paul gives us a quick lesson in power factor and Class D amplifiers. Have a question you want to ask Paul?

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  1. Mark Fischer on December 7, 2019 at 3:04 pm

    Power factor can be improved using power factor correction capacitors. The bad news is that you have to be an electrical engineer and know exactly what you are doing to size one properly. They are typically used in plants with large highly inductive loads. Increasingly they are being used in file servers because low power factors waste utility power.

  2. P V on December 7, 2019 at 3:06 pm

    No, most UPSes, even pure sine wave, are standby, which means they simply pass the power from the wall. Yes, they watch for low or high voltages and switch to battery as needed and have some filtering, but it is not what you think.

    You need an online UPS that is providing power all the time through the inverter, etc.

  3. Rajiv W on December 7, 2019 at 3:06 pm

    Majority of amps are class AB differential amps rejecting common mode signals like ripples or noise with feedback , rolled off frequency response to manage such issues. Line Interactive UPS is good for protecting power section of amps were power failure or fluctuations are problems, next choice is a good line filters. BTW Class D will "sort of" work even with cheap PC ups as the load is like PC SMPS

  4. Ped-Away-G on December 7, 2019 at 3:08 pm

    for a sound system? yes you can, why not? but it’s not worth the trouble.
    you could achieve pretty much the same result with a carefully designed power supply.

  5. Xip Xip on December 7, 2019 at 3:11 pm

    You must be a great guy to work for.

  6. bjornahh87 on December 7, 2019 at 3:12 pm

    I think my line-interactive UPS from apc with the filtering set at high and set at 220v 50hz instead of 230v 50hz and a high frequency AC filter inline with my stereo amplifier works for me, and the ac filter was so easy to build myself too, when i get money I’m thinking of making a video of my setup since nobody here think’s it is possible…

  7. Anil George on December 7, 2019 at 3:15 pm

    Inspiring as always, Paul!

  8. Geerladenlad on December 7, 2019 at 3:16 pm

    You’re going to have to film a new intro video in front of the new building.

  9. creidiki on December 7, 2019 at 3:16 pm

    Hey Paul. The word you’re looking for is line-interactive UPS.

    Regarding that, since I too can’t afford a power plant, I’ve found a measure of success in using greatly overspecced (1200VA) line-interactive UPS, one of the slightly more expensive semipro variety that makes a "proper" simulated sine wave rather than the cruder stepped-square wave models, followed by a DC offset filter, followed by a 1KW ACUPWR USA 240-240 regulator/filter with a PSAudio noise harvester stuck in on of the sockets.

    Its probably slightly worse than not having the UPS when the line is clean, but in a condo with electrics from 1968 Italy, plus countryside italian wall power, that doesn’t happen often, and my multibit DAC really hates being turned off for any amount of time so I needed a ups for it anyway.

    Since the load is just the DAC plus a SET 2A3 amplifier, and the UPS so massively over spec, I can brute force my way around the pf-induced thd and the filters eat the residual. I can tell its working by how often your dandy little noise harvester blinks at me 🙂

    When the power is dirty, which is very often, the harvester after all of that blinks way less than one I just stick into a wall socket, and I don’t hear all the grunge I otherwise do. I call that a win.

    For my other systems (like my bedroom 2ch with nice ATC bookshelfs but otherwise nothing really special) with lesser less finicky DACs, just the DC filter -> regulator + harvester seems to do just a-ok, although I can hear the filter’s voltage regulator modules engage/disengage when the neighbours use their electric window blinds, which I can’t with the main setup.

    So, if you absolutely can’t afford a PSA power unit, and the noise from an on-line double conversion UPS’s fans are no-go because you don’t have a separate room for it, you can make it work by massively overspeccing on the UPS, and it will be better than just filters, but I would only recommend it if you have particularly bad power, as the setup becomes rather complex. Or if you need uninterrupted power *anyway*.

  10. Євген Домашець on December 7, 2019 at 3:17 pm

    Thank a lot !!

  11. Trevor M on December 7, 2019 at 3:18 pm

    Hi Paul. Great Vid. This has been talked about before but you havent really mentioned you can buy an online double conversion UPS that is 20A or 30A output capable for around 1200$ these days. I own a cyberpower OL2200RTXL2U to run 3 zones of AV gear in my home. It is remote located in my mechanical room and I have dedicated runs leaving from it to each zone feeding a quad receptacle in wall. I have never noticed any brownouts voltage wise, and total current output is rarely over 4A. With 20A (1800W/2200VA) capacity I am no where near peak ,not rms, current demand ceiling. With 2 zones of audio gear running I am still not even close to taxing it.

    Buy a beefy double online conversion UPS, like a OL2200RTXL2U, and forget about it. Run it in online mode, not line interactive, all the time. Will this make your audio better? I hope not. It points to flaws in your gear if so. Use one to prolong your gear longevity from issues on the utility side. This will theoretically make your gear last indefinitely. If multi million dollar IT rooms run on them…… I’m covered. 👍

  12. Christian Goergen aka AstraOovier on December 7, 2019 at 3:18 pm

    And what about using a power conditioner for the UPS?

  13. CAP on December 7, 2019 at 3:20 pm

    I don’t understand how regenerating an AC waveform is supposed to improve your power supply in your downstream equipment. Your power supply should be able to handle and fix most AC issues to deliver DC current to the amplifier as long as the incoming voltage and current is within normal limits.

  14. John sweda on December 7, 2019 at 3:21 pm

    You can run a mains contestant lightbulb of 5 Watts before your amplifier or equipment will smooth out the signal and preferably a variac as well. I was wondering about running a contestant lightbulb after the Bridge rectifier to cut out noise?

  15. Big Dally C on December 7, 2019 at 3:22 pm

    I’m having such a hard time just getting a straight answer. What’s a good affordable solution to power? Is an AC filter the solution? If anybody would like to throw out a couple of suggestions, I’m all ears!

  16. Janina Palmer on December 7, 2019 at 3:23 pm

    What’s so wrong with the AC supply over there in the States ?? Is it the fact that you guys are using junior voltage class of 120… or what ? You have the disadvantage of having to make up the power consumed by doubling the current ( which could be brunt of all your problems .. I don’t know ..) but here in Australia we enjoy a healthy 245vac supply and much lighter currents… in my opinion power line filtering and low impedance cabling is all you need … here, a P20 module would be a total waste of money …

  17. Bradley Smith on December 7, 2019 at 3:23 pm

    Sorry, I have to disagree.. A power conditioner does little. But the one thing that it does well is group the AC receptacles together to prevent ground loops, especially in unbalanced systems. Of course, a quality power tap/strip will do the same thing.

  18. Mi Fang on December 7, 2019 at 3:25 pm

    i tried and did it with a big new ups I could borrow from a company director to try my idea . I needed to find a solution to get the fan noise to a minimum from the ups so I puted in a room next to the dedicated audio room. I played with Denon pre and 4 poa 6600A mono amps on infinity kappa 9A. i did it during different moments day and after midnight. it was no success. 14 days trial A B testing. doesn’t work…Paul has it right. I wonder with a ps audio…

  19. Maarten c on December 7, 2019 at 3:26 pm

    If your powerfactor is smaller then one your load is inductive our capacitive . If your load is inductive you can get closer to one by adding a capacitor. If your load in capacitive you can add a coil, to make the powerfactor 1. In formula make xl=xc.

  20. Stephen Burgess on December 7, 2019 at 3:27 pm

    Message to anyone who owns a power conditioner, an expensive network streamer or expensive speaker cables. I have some excellent snake oil for sale. Cures cancer and everything. On sale at the moment for only $2000 per bottle. 😂

  21. russmaleartist on December 7, 2019 at 3:27 pm

    Best to you in your new building.

  22. Viet Luu on December 7, 2019 at 3:28 pm

    I just bought a Zero Yeti 1000. It uses Lithium battery to do the regeneration work. So far, I see some improvements in my system (quite noticeable actually). The improvements are mostly at the high frequency and upper mid range.

    My system consisted of : KEF ref1, Mark Levinson 27.5, Audio Research LS26, and a Marantz CD player.

  23. Ka Lun Thomas Li on December 7, 2019 at 3:29 pm

    New video in new building should have a NEW header video at the end with the new building

  24. Ramon saunders on December 7, 2019 at 3:31 pm

    Hey paul, since your in a new building and all, are you going to bust the drone out and produce a new introduction video clip for the channel?

  25. Bogdan Serban on December 7, 2019 at 3:31 pm

    What a load of bs. Any amplifier takes AC and converts it to FILTERED DC. No matter the type of power supply, it does not care about how clean your AC is. Investing in a "power regenerator" and hearing a difference means that you belong in a mental institution.

  26. Grandma's Malibu on December 7, 2019 at 3:34 pm

    I finally understand what the Power Factor measurement means. So simple even I can understand it now. I could never figure out how Wattage and Power Factor related to each other, now I think I get it, at least sort-of.

  27. Carl Capps on December 7, 2019 at 3:35 pm

    The power supply is probably the most important part of any amp My Adcom power amp Year 1986 is a good example but compared to my Crown digital pro amp which cost less than the caps in my Adcom, Analagy for you to figure out my fellow audio Fanatics.

  28. twochaudio mg on December 7, 2019 at 3:38 pm

    answer is no get to it

  29. bvocal on December 7, 2019 at 3:41 pm

    My UPS, which I studied and choose on purpose for it’s quality… does not touch the power unless it falls outside of the set range for ‘normal’, and that isn’t very often (where I live now), unless you live in Colorado…

  30. thisrocks88 on December 7, 2019 at 3:44 pm

    I run my amp through a decent online UPS because I also run PowerLine “Ethernet” through my house and the alternative is an annoying low frequency hum which the UPS gets rid of.

  31. fookingsoc on December 7, 2019 at 3:46 pm

    A generated true sine wave is analog by nature…smooth. it’s only when it is (re)generated by a UPS inverter circuitry generating from the built in battery does the inverter *try* to *approximate* the sine wave. And truly, if you wanted more consistent power, it would be better to use a 3-phase circuit which can better supply the necessary current in a more fluid manner!!!

  32. BaconByte on December 7, 2019 at 3:47 pm

    If you need an expensive piece of gear to "clean" out the AC going into your stereo your stereo is poorly built and has shitty filtering in the power supply.

    Get a better stereo. Its a cheaper solution.

  33. Mark Beeunas on December 7, 2019 at 3:48 pm

    Google: ‘double conversion ups sine wave distortion’. Cheers, Mark * * *

  34. LRoy Shreding on December 7, 2019 at 3:52 pm

    The Cheapest power conditioner is a True Isolation Transformer ! Plenty of Current and Nothing is Touching the Power Source ! Some Iso Transformers have Ground Connected .

  35. imark7777777 on December 7, 2019 at 3:53 pm

    The new video makes a nice companion to this one.

  36. Jason Setiawan on December 7, 2019 at 3:55 pm


  37. Perhaps on December 7, 2019 at 3:55 pm

    "… since they regulate the voltage, clean the power, and check constantly the sine wave when necessary …"

    Some do.
    Most do not.

    Most UPS’s are referred to as a "bucket of batteries", because they do nothing, other than switch to battery power, upon a blackout or brownout.

    And, as Paul mentioned, when they switch to battery power, they do not produce a sine wave (and for audio gear, you want a sine wave).

    Why a bucket of batteries? Because that type of UPS is primitive (not much that it needs to do), and, therefore, cost less to manufacture, and cost less for us to purchase.

    There are also line-interactive UPS’s, that will trim or boost the voltage, as needed. But it is not a precise adjustment. These UPS’s will initiate an adjustment, only when the voltage hits a certain range. Anything within its range (within its tolerance) will be ignored. Meaning, if you have low voltage from your wall outlet, as long as it is not too low, the UPS will ignore it. And when the UPS does get triggered to make a voltage correction, it is not subtle, and you will likely hear it.

    Then there is the "on-line" UPS. These offer the best protection, and will empty your wallet.

    To get a UPS that delivers a sine wave, that does the double conversion, will raise the price significantly.
    Such UPS’s do exist. But for home use, the choices are very limited. If you want to run a data center, and spend tens of thousands on a UPS, then more choices open up.

    Also note that the double conversion UPS’s use electricity every second that they are on. It is not free to convert electricity from A/C to D/C and then back to A/C, which is what this type of UPS does. So for every 100% of juice that enters the UPS, the UPS outputs typically between 90% to 95%. So you will have an electrical bill increase.

    I have never seen a review to determine if any double conversion UPS’s help with better sound (and it will differ, depending on the quality of the sine wave in your home, which will be different for everyone). If your utility company delivers crappy power, then a double conversion UPS will probably help. If your utility company delivers quality power, then a double conversion UPS might do little, if anything, or might even be somewhat detrimental to getting better sound from your gear.

    And then there is the noise that double conversion UPS’s make. They are quiet. But they are intended to run computers, where a whisper of a fan, for example, is acceptable. But for your music? Any extraneous noise is a red flag.

    Lastly, can a double conversion UPS deliver the sudden power demands that amplifiers will draw, in order to not starve the amplifiers for that initial leading edge? Or will the "slam" of the moment be dulled?

  38. Derek Gebhart on December 7, 2019 at 3:55 pm

    Now that you’re in your new space, are you going to redo the end video drone shot of the staff in front of the building?

  39. Mark on December 7, 2019 at 3:56 pm

    You mean the guy who wears a brown uniform and drives a brown cargo van and leaves the big package on my front porch so Larry Light Fingers can steal it? Oh! …here every Friday night and don’t forget to tip your waitress!

  40. Joe Home on December 7, 2019 at 3:56 pm

    Don’t use UPS. They are not as expensive as others more expensive.

  41. ThinkingBetter on December 7, 2019 at 3:56 pm

    My power plant is a huge natural gas powered plant delivering max somewhere around half of a Gigawatts of pure 60Hz clean power via some transformers and wires to my amplifier, which does an excellent job of re-generating that 60Hz AC into a clean DC power to the amp electronics, which feeds a high quality music signal to my speakers unaffected by the noise from other power consumers. 🤔 is that DC voltage really clean from noise on the grid? In my case, yes. If you have an oscilloscope and some braveness, try measuring it. Let me know if you are one of the 0.1% with such problem and please post your measurement. Perhaps your problem is that your amp power supply is just poorly designed? Try to add a cheap line filter 😂 Well, perhaps some regions of the planet have much worse power. Perhaps you share power with an elevator motor?

  42. Jon Rock on December 7, 2019 at 3:58 pm

    I had to get one because I moved into an old apartment and my computer blew, my expensive LCD blew and then I finally bought one. New Computer and LCD didn’t blow the remainder of the 5 years I lived at the apartment.

  43. Mark Fischer on December 7, 2019 at 3:59 pm

    Hi Paul. The term you are looking for is line interactive. This type is satisfactory for computers but probably not for high end audio equipment. They can be as high as 40 percent THD. They are relatively inexpensive and for a typical desktop computer can run about 200 or less. I have an Eaton 1000 VA 600 watt model myself. Double static conversion models are much more expensive. Power factor of the load can be improved by adding capacitors sized for each load
    UPSs and generators like power factors between 0.8 and 1.0 lagging meaning net inductive. UPSs can be bought at any size up to about a million watts. Capacity can be further increased including by installing them with paralleling units. THD is typically 5 percent or less, around an order of magnitude worse than a PS power regenerator.

  44. hifi noob 2018 on December 7, 2019 at 4:00 pm

    So what did we learn? That’s right…… we all still need a PS audio power supply…… imagine that. LoL

  45. Sirflatch on December 7, 2019 at 4:00 pm

    Thank You for all you do !!!!

  46. TheTrueVoiceOfReason on December 7, 2019 at 4:03 pm

    You could always look up Brick Wall power products.

  47. Chill Bill on December 7, 2019 at 4:03 pm


  48. Craig Spurlock on December 7, 2019 at 4:03 pm

    I once made the absent-minded error of plugging in a small vacuum cleaner to my UPS. BEEP BEEP BEEP BEEP! Right out of the box my Sony XBR900E had a weird pulsing in the screen backlight, tried it on the UPS, and it cleared right up. As long as you watch your loads, and get an "online" UPS, it is a good budget way to get in the game. I mainly wanted one for the battery backup, to keep the DVR online during power cuts.

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