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Power generation using electric motors

  1. Mar 24, 2009 #1
    Hi, I am a novice. I have very sensitive high end audio equipment. I want to power them up from an independent source. I was contemplating using a electric motor driven generator. I want to do this to supply cleanest power to the equipment/electronics. My power requirement is about 5 KVA. I am planning to make three such sets of 2KVA each to supply to my three sets of amplifier's. I do not want to use any fuel based prime movers.
    I would appreciate any suggestions.
  2. jcsd
  3. Mar 24, 2009 #2
    What is the "Normal Source" that you want to be independent from?

    Need to know more about the existing source and identified problems before even making a guess.

    Removing any "fuel based" motors pretty much eliminates all viable options, other than running a portable nuclear reactor, unless that too is "fuel based".

    In a country with a stable electric grid, you won't find a cleaner source of power than the grid.
  4. Mar 24, 2009 #3
    my normal source is the grid. But. as usual, many electric items are connected to my home power source (both inside and outside) which do carry electrical noise. Hence I want a dedicated power source to run just my audio equipment. and nothing else will be connected to it.
  5. Mar 24, 2009 #4
    The AC power is filtered, converted to DC and heavily filtered more to eliminate the 120Hz Ripple. These steps make any noise on the AC line isolated from the audio signal. If the power is stable enough to run a PC, Display, etc, the AC line is OK.

    If there is audible noise from the power in the audio output, the power supply in the amplifier needs repair.
  6. Mar 24, 2009 #5
    i agree. but i have heard amplifier running on an dedicated power source and it sounds so much more cleaner with a much lower noise floor. The transients in the music are more pronounced and impactful. If i understand right the more components there are in a circuitry more is the contamination in the signal path. though i cannot get rid of the components in the signal path, the least i can do is to supply a pure sine wave power which makes the components in the signal path less obstructive... pardon me if my concepts are out of context, as i have no knowledge of electronic circuitry...
  7. Mar 24, 2009 #6


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    How do you know that the differences you heard were due to the power source? Did you listen to the same system with both grid power and the independent source? If not then how do you know the difference was due to the power?

    Read Bipolars posts, if you do not understand what you are reading please ask questions.
  8. Mar 24, 2009 #7
    yes i have heard the same system on both power sources separately. Hence the observation. "Bipolars posts" = where? link?
  9. Mar 24, 2009 #8
    Any transients/noise floor that are audible are due to the internal amp power supply, or a different location/position of the amplifier and system, and not related to the power source.

    As I stated, if your household source did have enough noise to get past a properly designed amplifier power supply, then your computer would not run.

    Please read http://sound.westhost.com/cables-p4.htm#power for some more information regarding supply quality and AC related to audio amplifiers.
    Last edited by a moderator: Apr 24, 2017
  10. Mar 24, 2009 #9
    Way cool dude. Peddle power you drums, man. Maybe, like, instead of a dancing chorus, you could have a peddling chorus.
  11. Mar 24, 2009 #10


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    Don't you guys know to never argue with an audiophile?
  12. Mar 24, 2009 #11
    I cant really believe someone has actually been taken in by that pure supply nonsense.

    A local generator will produce a noisy spikey output anyway.

    Do you spend £20 a metre for speaker cable as well?

    A fool and his money.......
  13. Mar 24, 2009 #12


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    If it was designed/built correctly
    PCs used switch mode PSUs that will run on absolutely anything.
    Probably true, or an earth loop, or a bad ground.

    If you are really fussy cut out the AC power supply and run the amplifier directly from a 12V battery
  14. Mar 24, 2009 #13


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    I'd say the first step should be to put the DC output of your amplifier's power supply on a scope, and measure the noise, transients, ripple, etc. that's present. After you've proven the power supply to be inadequate, then you can work on a solution to improve it.

    Throwing money and effort at a perceived (but unproven) problem is silly. If you're into high-end audio, you're probably already used to doing this, unfortunately, since that's the essence of the entire hobby -- making yourself feel better about your equipment by throwing money at problems you can't really perceive and don't really understand.

    If you really want to spend money to improve your music-listening experience, I'd suggest some insulating wall coverings, or maybe just a rum and coke. Enjoy.

    - Warren
  15. Mar 24, 2009 #14


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    You hit the nail on the head here. The audiophile community likes to perceive problems that cannot be proven whether or not they really exist. This way, there is an endless amount of money or effort that can be thrown at the perceived problem. If you cannot prove with instruments that the 'problem' has been fixed, then technically it's still there. Those of us who claim that there was no 'problem' to begin with don't seem to count.
  16. Mar 24, 2009 #15
  17. Mar 24, 2009 #16


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    There are many, many audiophiles who claim that electronic measurement equipment cannot detect the subtle qualities of music that are affected by, say, power conditioners. Despite the clear and obvious truth that the electronic measurement equipment is far, far more sensitive than human ears, they wish to rely on their ears alone as a guide for spending their hard-earned money.

    What's really shocking is that there are many audiophiles who further reject the notion of double-blind testing. This means they not only distrust electronic measurement equipment, they also distrust their own ears -- the same ears they are supposedly trying to please in the first place.

    After rejecting the results of both measurement equipment and double-blind testing, audiophiles are no longer vulnerable to any rational argument. Instead, they follow their instincts and collect vast amounts of shiny, overpriced nonsense. The enjoyment of music eventually becomes confused with something even more fundamentally human: the pride of ownership.

    If all you seek is pride in ownership, you'll always get what you pay for.

    - Warren
  18. Mar 24, 2009 #17
    If your equipment is properly designed and built, the power supply connections to all your low level stages should come from regulated DC supplies and be bypassed locally with caps to ground. The audible hiss should be only broadband noise, with no 60 Hz or harmonics. Also, the only noise or hiss should come from your first stage ( e.g., 12AX7) wih open input. Unplug it and the noise should go away. I had to run the filaments on my first stage with DC to minimize the hum.
  19. Mar 25, 2009 #18
    What about interference coming through the air and not necessarily through the electrical system. Interference could come from anywhere and then re enter the system after amplification or anywhere. Shielding the wires and amp might help.
  20. Mar 25, 2009 #19
    All low level signal amplification stages should be totally enclosed in metal enclosures (aluminum, except maybe copper at loweest frequencies), and all power leads shoud be bypassed (capacitor to ground) at the entry point. Input and output signals should be on coax cables with the shields well grounded. For loud (ground shaking) music, I would also isolate the amplifier stages mechanically so that vibrations do not shake the grid of your amplifier tube (e.g., 12AX7) and modulate the gain. Or I would use a low noise JFET instead.
  21. Mar 26, 2009 #20
    Hi Guys,
    Thanks for the great "eye openers". I am better informed now. And incidentally I AM NOT AN AUDIOPHILE. This was an idea that was thrown to me and i do make it a point to research well before i take the plunge. and that includes talking to professional's in the field too. And I did read bipolar's link. Thank you guys. Incidentally i have corrected the room acoustics problem before i ventured in upgrading to any equipment. My head is on my shoulders!! unlike "AWED-DIOPHILES". Thanks again
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