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DIY Studio Power Conditioning / cleaning up dirty power

Discussion in 'Pro Audio Equipment' started by audiokid, Mar 18, 2009.

  1. audiokid

    audiokid Staff

    I'm wondering if I could build something to help with power conditioning, cleaning up hum/ dirty power for my project studio. Does anyone have a solid design or know of a kit that I could make that would work excellent?

    Any suggestions would be great.
  2. jammster

    jammster Active Member

    audiokid, I had this concern for a time and thought by running a UPS battery backup or line conditioner it would solve the problem.

    I still have not yet done anything to solve my concern. I run a small home setup. I need to do my math and find out how many watts I need. Here is an example of a system that runs 780W peak.



    It seems to me when your dealing with power it may be better to have a device that is tested and backed by a warranty to keep your valuable studio functioning properly.
    I hope this helps you,

    Edit: scratch that triplite, its a bad product after reading some reviews at newegg, the the APC.
  3. RemyRAD

    RemyRAD Well-Known Member

    Short of spending a fortune for something such as a Liebert Computer Power Distribution System one might want to consider this?

    While you might think a stock UPS, designed for uninterruptible power? It doesn't necessarily provide for any isolation, electrically. Surge suppression from general-purpose surge suppressors, already exceeds voltages that most audio equipment can't tolerate. Serious surge suppression costs real money.

    A power transformer can provide for electrical isolation & a type of balanced power distribution. These power transformers will also provide for a limited bandwidth to also prevent a higher frequency interference from infiltrating your equipment. This is what I've used in my remote truck for the better part of 18 years. Thanks to Kooster McAllister of Record Plant Mobile for turning me on to that so many years ago. You can use these transformers to step up & step down voltages as well. But it's the similar wiring to a balanced audio circuit that does the trick. I would do the same thing for a fixed installation studio assigning the transformer for technical use only. Not for use on lighting or air conditioning, not needed there. The operation of the transformer provides for filtering by virtue of its operation. Further filtering can also be utilized if you feel the need. I haven't and it hasn't been a problem for over 18 years. Transformers are our friends. I run a 75 amp unit & Kooster runs a 100 amp unit on his truck. Manufactured by Signal Transformer Company.

    This is not a typical balanced power distribution scheme as others. Those types literally split the voltage between neutral & hot. You'll get 60 volts with reference to ground from neutral as well as 60 volts with reference to ground from hot. In assistant I'm using, the input voltage is balanced on the primary of the transformer. The output side, the secondary, the power is as normal. That is zero volts with reference to ground on the neutral & 120 volts with reference to ground on the hot. Neutral is derived from the center tap of the secondary. So the output total voltage is balanced but is used in an unbalanced like configuration. Not necessarily something that follows standard construction code protocol. It's audio wiring not standard house power.

    I'm charged up over this!
    Ms. Remy Ann David

    I love my transformer
    Ms. Remy Ann David
  4. iamfrobs

    iamfrobs Guest

    So that little Furman I thought of as protection is actually not much?

    heh...let the innuendos fly RO
  5. audiokid

    audiokid Staff

    Remy, what transformer product and how does one hook this up? Can you explain the way to wire this more in detail?
  6. audiokid

    audiokid Staff

    Hi Bret, I bought that exact APC at Costco, works great but see it only as a power backup and, hope it will save things from a surge.
  7. dvdhawk

    dvdhawk Well-Known Member

    How much current are you trying to condition audiokid?

    I don't know which 'little Furman' you have iamfrobs, but I'm sure the power coming out of it is probably an improvement over the junk coming out of the wall.

    A DIY project on the scale of what Remy is describing would require a massive 60V + 60V center tapped toroidal transformer and the means to lock the second leg 180˚ out of phase with the first, creating the 120V potential between the two legs.

    There are numerous 20A balanced power commercially available, I'll be watching with great interest to see if you can build one any cheaper than you can buy one.
  8. audiokid

    audiokid Staff

    Hey, thanks for the links dvdhawk! They aren't cheap I see.

    I'm thinking 30 amps and possibly 45 tops.
  9. RemyRAD

    RemyRAD Well-Known Member

    You can certainly do this with a much smaller transformer. Those American to European converter transformers are small and good for up to 20 amps. Get a couple of them, they're small.

    I didn't use a Toroidial transformer, popular in balanced power systems but a Power Isolation transformer. This thing appears more like a large power supply transformer or a small UTC style audio transformer. It's not balanced in the typical sense of trying to evenly split the phase of 120 volts, in half.

    The primary side has dual multi-tapped primary windings. The multi-tapped section allows for different primary voltages of 240/220/208/120/110/104 single phase or triple phase. The two primaries are tied together at the center. High side voltage is applied to each side of the primary inputs. No ground. No neutral. Just two hots. + & +, that's all.

    On the secondary side, you want the lower voltage to power the equipment. So, those dual secondary windings are also tied together at the center tap of the two windings sets. The center tap then becomes your neutral. You then can use the multiple taps to extract 120/110/104 volts, as needed/required.

    Because the power is connected to the primary of the transformer in a differential manner, all interference common to those power rails cancel out within the primary of the transformer. This provides you with clean, noise free power from the secondary windings. The frequency response of the transformer also isn't what we would call high fidelity. This works very much in your favor when dealing with high frequency electrical interference. It just doesn't make it through the transformer.

    You don't have to feed the equipment balanced power to be using balanced power. It's quite funny to get Master Electrician's scratching their heads when you have no neutral & no ground tied into their shore power. No, I don't drive a stake into the ground either. I like the feeling of floating. Don't you? This ain't your grandmothers electricians electrical wiring. And not necessarily something you want built into your walls since it probably falls outside of normal wiring procedures & Building inspections. I can get away with murder for mobile applications like this. Maybe murder wasn't a good word to use?

    I think I'm taking too much estrogen??
    Ms. Remy Ann Davizzzzzzzap!......mumph.......
  10. AudioGaff

    AudioGaff Well-Known Member

    Remy has rit ight. You want or want something like Furman makes. I have the IT-1220 in use for many years now that has been 100% reliable. The newer models are even better.

    Most power conditioners regardless of their claims, have very, very little power filtering. In the IT-1220 I own, it has beter than average filtering, but the balanced power thing makes the bigger difference as it reduces overall noise by several dB and takes care of most ground loop issues.
  11. audiokid

    audiokid Staff

    Thanks for the feedback, I've learned some important stuff here.

    I'm looking at this beast. http://www.furmansound.com/product.php?div=01&id=IT-20_II
    Does this plug directly into a 110 volt/ 20 amp socket?

    They have smaller, more affordable units but they don't specify being balanced and critical high end quality.

  12. dvdhawk

    dvdhawk Well-Known Member

    Yes, that's right audiokid. The IT-20 plugs directly into a 20-amp receptacle and has 12- filtered outlets on the back and 2 on the front. You use it just like any other power strip. But it's a really big 80-pound toroidal filtered power strip that can lower the noise floor of your entire system.

    The IT-20 is the only balanced power unit Furman offers right now, but there are other manufacturers that make balanced power supplies. [Equitech & Monster come to mind]

    Furman's smaller, more affordable units are not balanced power, but offer varying levels of filtering, surge protection and line conditioning all the way up to the AR-Pro which is actually pricier than the IT-20.
  13. audiokid

    audiokid Staff

    Man, maybe I'm looking at overkill. I've found this simple rack unit: PL-8 C



    Maybe I don't need all the amps I thought. "nough to power your whole home studio".
  14. audiokid

    audiokid Staff

    Hi dvdhawk,

    I posted before I saw your reply. Sounds like the balanced is critical if you want to improve the sound quality.
  15. dvdhawk

    dvdhawk Well-Known Member

    The standard filtering technology does a pretty good job too. I've seen it do wonders on the live gigs.

    With any of the 20-amp units they come equipped with a rea 20A plug.

    Like this:

  16. audiokid

    audiokid Staff

    is that 220 volts?
  17. jammster

    jammster Active Member

    This is really good info here you guys!


    I like Remy's suggestion with the simple step up / step down transformers one up to 220 then back down to 120. I found these transformers that look reasonable.

  18. dvdhawk

    dvdhawk Well-Known Member

    No, that's a proper 20-amp 110v/120v blade configuration. That's the female you're looking at. Lovely isn't she?

    Furman and others sell a little pigtail to adapt it the standard parallel blade 15-amp config. They also mention in their manuals the reality that you may want to lop the 20A plug off and put on the more standard plug. But they strongly suggest you make sure your circuit is a 20A if you do that.

    Even if your breaker is 20A, they assume you won't be dropping the entire load on one 15A receptacle.
  19. audiokid

    audiokid Staff

    Thanks for taking the time to explain all this guys. Great info here.

    Now... 20 bucks for a step up/down transformer. I like the price of that lol! What are we paying for with the custom products like Furman?
  20. dvdhawk

    dvdhawk Well-Known Member

    $20 for 500w? That's just over 4 amps if the 500w rating is at 120v. How do you plan to apply the step up/down? I don't believe it's the same thing. To do something like Remy has, won't you need two of the big boys? I'd love to know a better cheaper way!

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