Members greendoor Posted August 1, 2005 Members Share Posted August 1, 2005 That's Balanced AC power, as defined by www.equitech.com not phantom power. The theory is similar to the theory behind balanced audio - expect it's applied to your AC power, the biggest source of mischief and mayhem in your studio. Balanced AC power is Two Phase, as opposed to normal single phase. But it is NOT simply two phases taken from the regular three phases that are normally available. Those two phases would not be exactly 180 degrees apart, and would not work. As I understand it - in laymans terms: instead of 120 volts AC, with an earth, you use a centre tapped isolation transformer to create a 60V+ - 0V - 60V- secondary. That's two phases of AC, 180 degrees apart, with a common centre tap earth. Apparantly, the biggest source of electrical noise is caused by digital switching and other electrical problems that dump spurious currents in earth. That can be from appliances your neighbours up the street are using, to the power supply in your PC or digital audio gear. You think of Earth as being zero volts, but it is anything but - there's a lot of crap coming through the Earth. If you have balanced power installed, for a start you have the benefit of an isolation transformer. Second, you have the benefit of a dedicated earth, which is referenced to the centre tap on your transformer. When these stray earth leakage currents enter the transformer, they enter both sides of the power supply, and because the two sides are out of phase, they cancel and null out. Problem solved. It apparantly kills ground loops at the source. People report a typical 6dB reduction in noise floor, in all componets. Video monitors stop getting white flecks. Digital jitter goes down. The difference between a lot of expensive audio gear and the cheap stuff is often because of power supply design. With balanced power, allegedly cheap gear can sound as good as some expensive gear. Seems like some worthwhile improvements. I've heard of some audio engineers who travel with balanced power conditioners, and allegedly the top studios making the hits all use balanced power. I've got a 5kVA transformer made, but not installed yet. That will take some major renovations, and the wet weather here is slowing that down. Anyone else on to it? Any believers? Unbelievers? Testify! Link to comment Share on other sites More sharing options...
Members where02190 Posted August 1, 2005 Members Share Posted August 1, 2005 We run all the control room electronics through a balancing UPS, and it made an immediate and huge improvement on the audio quality. the noise floor is incredible, I can open every fader, every gain pot to max, and put the console at +10 with the control room monitors cranked and it's dead quiet, you have to put your ear to the speaker to hear just the slightest bit of hiss. Balanced, regulated power is totally worth it's weight in gold. Link to comment Share on other sites More sharing options...
Members Kiwiburger Posted August 1, 2005 Members Share Posted August 1, 2005 That's what I want to hear ... silence. Link to comment Share on other sites More sharing options...
Members gruvjack Posted August 2, 2005 Members Share Posted August 2, 2005 Most intriguing I'm interested in looking at a 240VAC system. Are there any particular manufacturers or vendors that anyone can suggest/recommend? BTW, I'm in Malaysia. V. Link to comment Share on other sites More sharing options...
Members kylen Posted August 2, 2005 Members Share Posted August 2, 2005 I run Furman power regulator (AR1215) and balanced power (IT1220) in the bat cave here: http://www.furmansound.com/products/pro/reg/reg1.php http://www.furmansound.com/products/pro/blncd/balanced1.php After playing in clubs for a number of years and hearing how the sound of my amp changed every time I wasn't going to do my mixing and balancing connected to that junk! Same reason I don't drink the water directly from the tap I haven't spent the time to do any A/B or prove the expense was worth it - since I already believe it is, haha. I only hear music no floor or pops, ever. Link to comment Share on other sites More sharing options...
Members soundthinker Posted August 3, 2005 Members Share Posted August 3, 2005 Originally posted by where02190 We run all the control room electronics through a balancing UPS, and it made an immediate and huge improvement on the audio quality. the noise floor is incredible, I can open every fader, every gain pot to max, and put the console at +10 with the control room monitors cranked and it's dead quiet, you have to put your ear to the speaker to hear just the slightest bit of hiss.Balanced, regulated power is totally worth it's weight in gold. What UPS do you use? /jim Link to comment Share on other sites More sharing options...
Members The Chinese Posted August 3, 2005 Members Share Posted August 3, 2005 Originally posted by gruvjack Most intriguing I'm interested in looking at a 240VAC system. Are there any particular manufacturers or vendors that anyone can suggest/recommend? BTW, I'm in Malaysia. V. http://www.equitech.com/index.html They'll make you any tranny you want. I suspect that your grid is similar to Thailands, which is a mess....this is a good investment for you!!!! -Todd A. Link to comment Share on other sites More sharing options...
Members The Chinese Posted August 3, 2005 Members Share Posted August 3, 2005 Originally posted by soundthinker What UPS do you use?/jim I'll bet it's custom.... You would dneed a serious, 50-100kVA UPS to do a MR (Unless it's small....) -Todd A. Link to comment Share on other sites More sharing options...
Members where02190 Posted August 3, 2005 Members Share Posted August 3, 2005 Yes it is custom, bought from a computer company several years ago. they had literally hundreds of them that they used for their servers, but alas the company was seriously downsizing. they were going for pretty dirt cheap. It's huge, about 2x3x3, and weighs about 200lbs. It will supply 45 amps of cloean, balanced, regulated power, and will continue to supply that for up to 2 hours if there is a power loss. Link to comment Share on other sites More sharing options...
Members soundthinker Posted August 3, 2005 Members Share Posted August 3, 2005 Yes it is custom... that's what I was thinking too... /jim Link to comment Share on other sites More sharing options...
Members umkcprof Posted August 4, 2005 Members Share Posted August 4, 2005 This is a great and important thread. Here are my questions: REGULATED power seems less important to my "physics" brain than BALANCED power. The two Furman links posted above do very different things. One of them is a voltage regulator, while the other one is a powerline balancer. It would make sense to me that the balancing would eliminate undesirable hum and buzz, while the voltage regulator would have more to do (and even very little of this, I would think) with amplifier fading. Or am I nuts? (Okay, I AM nuts, but am I WRONG?) Is the Furman IT-1220 ($1130 at Sweetwater) a fine piece of balancing equipment? Is there something better out there for comparable money? Will I really notice a noise floor difference? Thanks much. Steve Link to comment Share on other sites More sharing options...
Members Kiwiburger Posted August 4, 2005 Members Share Posted August 4, 2005 I agree that the 'balanced' 180 degree two phase part is the important factor here. That requires a transformer - and that is the heavy, expensive part. I think Furman and others market a wide range of products, and most of the cheap/lightweight ones are gimmicks. You need to read very carefully exactly what type of protection it is giving you. For the sort of kVA power a studio needs, the transformers need to be huge. To keep the costs down, the commercial ones tend to use toroids. (That's where the core of the transformer is simply a coil of wire - much easier to make). Toroids have pro's and con's. Pro: They are cheap, they are fairly efficient due to the tight coupling between coils. Con: they don't have the magnetic reserve capacity to self start - the starting current is simply too great, so they need special start-up switch arrangements. The don't filter out AC line noise as well, because of the tight coupling between coils. I live in NZ, and nobody knows about balanced power here. Importing a heavy transformer would have cost more in freight than the product, and I need 240v. So I got a local transformer winder to make me a 5kva trannie with a centre tap. I've had it for a couple of months and haven't installed it yet - other things going on. I'll post back when i've installed it. I have a guitar room that I want to get deadly quiet (electrically - it's already deadly quiet acoustically). I get a lot of crap through the AC ground, and I have to suck on a wire when playing. I want to feed it balanced power, and if I have to i'll install a faraday cage. Link to comment Share on other sites More sharing options...
Members kylen Posted August 5, 2005 Members Share Posted August 5, 2005 I think if anyone wants to get stats on the power condition at their local plug, on their local power grid it should be fairly convenient to rent a power analyzer for a day or 2 that will give you printouts, 8x10 glossies - you know details about what the heck is on each leg of your power and grounds and neutrals. That might help you to decide if you need to level sags & surges or just focus on pops & clicks. I took care of both issues when I had the money - it wasn't too expensive for my little laboratory. I also threw a little 30minute UPS in there for the single DAW. As far as the Furman balanced isolation transformer I pointed to earlier it weighs a ton and is on the bottom of my mastering rack, supported with a standoff at the rear of the case. It's not something I wanted to hang up high! Link to comment Share on other sites More sharing options...
Members The Chinese Posted August 5, 2005 Members Share Posted August 5, 2005 Originally posted by kylen I think if anyone wants to get stats on the power condition at their local plug, on their local power grid it should be fairly convenient to rent a power analyzer for a day or 2 that will give you printouts, 8x10 glossies - you know details about what the heck is on each leg of your power and grounds and neutrals. This is actually a really good idea. However, you can get an indication just by using a Volt meter, preferably one that measures dB and Freq.... check your Ground Plug Against a Known solid Ground. should be no Current. Less than 1V is OK. If you start seeing more than that, there is trouble. Now test your Neutral Across your Ground. Again, should be zero. If you see Current here, there is a problem. notice what frequencies they are at... Switching noise is REALLY high Freq and will show. If you have a scope you set it to look at the sine wave...optimumly, it should be a perfect sine wave, but this is rarely the case...There is usually some distortion right at the top of the curve (even in a balanced systemmm). FYI!!!! -Todd A. Link to comment Share on other sites More sharing options...
Members where02190 Posted August 5, 2005 Members Share Posted August 5, 2005 Neutral to ground voltage should not exceed .1volts, not one volt. Link to comment Share on other sites More sharing options...
Members Robman2 Posted August 5, 2005 Members Share Posted August 5, 2005 MY friend Paul du Gre' has a built into wall unit that looks like one third of a washing machine, cost him a lot of dollars...but the rooms clean. Link to comment Share on other sites More sharing options...
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