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11,500va Balanced Power Transformer
Old 29th April 2017
  #1
Gear Nut
 
DeyeYguy's Avatar
 

11,500va Balanced Power Transformer

... preparing to be install in my studio. It's a 200lb Plitron 60-0-60 toroid that should give me 5-20 amp 60+ 60-balanced center tapped circuits. The reason i'm posting in high end is because they are expensive and only someone with a high end studio would even bother to do this, so i figured the experienced would be here. I'm looking for any insight some may have to installations on these? I'm reasonably seasoned with commercial/residential electricity as a general building contractor, but this is new to me so i will be having a full time electrician contractor pal helping me with the installation, but in the meantime my plan is to educate myself as much as possible on BP systems. The plan as of now(subject to change via research), is a 40 amp breaker feeding off my mains panel via 8awg(mains only 5' away from BPT), to a ferrous metal box which will serve as a sub panel/single layer shielding around the MASSIVE tranny(i will wrap the tranny itself for another layer of shielding), their will be a grounding rod driven into/through the concrete slab and into the earth for the ground, i will feed 5-20amp dp breakers on the front panel of the box, steel MC 12-2 cable will serve as 5 equal length feeds throughout the studio, I will use bypass caps and EMI/RFI filter at the receptacles at specific distribution locations throughout the studio.

any insights from others who have specific knowledge, installation experiences, advice or thoughts are appreciated.

In case anyone is wondering what balanced power is all about, here's some good reading Balanced Power: The Next Generation
In short, and to the best of my knowledge, it's about isolated differential supplly legs that null/cancel/CMMR hash, hum and pollution noise off your mains that exists because you share them with everyone on your block who shares the same pole transformer, all their appliances media junk, all your appliances media junk and their crappy switching PSU are filthy, so BP in conjunction with filtering supplies your gear with washed and sanitized power, the cleanest power available short of powering your studio with batteries
Of course proper grounding is still and always a must, it certainly helps that each leg's ground is singular though.

data sheet and pic of toroid(spray paint can for size reference, i kid you not that 3 sizable dudes could not pick this up and walk with it, it's ridiculous size to weight ratio doesn't allow a good enough grip, and with 3 guys you can't get close enough to it so it exaggerates the weight, imagine trying to carry a 200lb slick basketball arms slightly extended... we were laughing our asses off at our embarrassingly futile efforts just to pick it up, and wondered how we were going to get it off the crate and inside.)
Attached Thumbnails
11,500va Balanced Power Transformer-screen-shot-2017-04-28-10.17.00-pm.jpg   11,500va Balanced Power Transformer-plitron.jpeg  
Old 29th April 2017
  #2
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drBill's Avatar
Tony - Ralph Skelton - Pacific Innovative Electronics in the valley.
Old 29th April 2017
  #3
Gear Nut
 
DeyeYguy's Avatar
 

Quote:
Originally Posted by drBill View Post
Tony - Ralph Skelton - Pacific Innovative Electronics in the valley.
thanx BP!(get it..., balanced power ) i'll hit him up, did you put a BP supply in your new place? Pretty sure you had one in your old place.?.?
Old 29th April 2017
  #4
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drBill's Avatar
Quote:
Originally Posted by DeyeYguy View Post
thanx BP!(get it..., balanced power ) i'll hit him up, did you put a BP supply in your new place? Pretty sure you had one in your old place.?.?
No... I'm not actually a huge balanced power fanatic. When it works, it's unbelievable, and other times, not so much. (Speaking of the equitec boxes) It's never "bad" though. Just (IMO) sometimes not worth the extra cost and effort unless you have serious problems. I've been lucky to be in places with great clean power though. I can definitely see the advantages in some locations, and have experienced the miracles first hand. I did not do balanced power in the new joint. Just put in conditioned, and surge protected power. I was a bad boy. I didn't even do a proper star ground, beyond the normal correct bay implementation and telescoped wires. I rolled the dice, and came out winning. I did pull all new power to it though, and implemented per Jeff Hedback's recommendations.

PS - ralph is a genius, and a great guy.
Old 29th April 2017
  #5
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here's a good read i found, good info, doesn't seem to confirmation biased
6moons audio reviews: Equi=Tech 10WQ
Old 30th April 2017
  #6
Lives for gear
 

Quote:
Originally Posted by DeyeYguy View Post
here's a good read i found, good info, doesn't seem to confirmation biased
6moons audio reviews: Equi=Tech 10WQ
Adding a transformer (Balanced power) to your mains is going to add impedance to the AC line and slow down the transiet response. In addition it will never equal sound quality wise, single ended power.

Now It will make you system quieter, but not at the expense of other things..

I have had clients do direct shootouts between balanced power and single ended power. And single ended power always won! In there eyes..

If you want a clean studio installation do a deep earth ground system coupled with your water pipe , and star ground and power every piece of gear in your studio! and make sure every piece of gear is isolated in wooden rack rails!

Now thats a quiet studio with performance
Old 30th April 2017
  #7
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Quote:
Originally Posted by MichaelAngelo View Post
Adding a transformer (Balanced power) to your mains is going to add impedance to the AC line and slow down the transiet response. In addition it will never equal sound quality wise, single ended power.

Now It will make you system quieter, but not at the expense of other things..

I have had clients do direct shootouts between balanced power and single ended power. And single ended power always won! In there eyes..

If you want a clean studio installation do a deep earth ground system coupled with your water pipe , and star ground and power every piece of gear in your studio! and make sure every piece of gear is isolated in wooden rack rails!

Now thats a quiet studio with performance
Thanx for the response, I'm already wood rack rails and star ground of course, i have the occasional hum, buzz and ? sounds jump in due to neighbors? cell phones? wifi? or whatever else may be causing it, that's what led me down the BP path. I noticed you said "your clients", may i ask what's your occupation? It might help me to connect the dots on your statement, and maybe allow me to look up some info corroborating the claims you made(i'm not saying i don't believe you, just interested in reading some data), I know EMI, RFI filtering, inrush suppressors etc. can add some R, but a raw toroid sitting at the front end should be negligible at most... no? A couple things i don't agree with above as of now, first, in all your gear the power supplies should be unaffected by proportionally appropriate mains supply from any source, their power transformers(and filtering) are in front of linear full wave rectified sections found in most pro audio gear(is there any other?), all have bulk capacitance beyond that point in the process of converting AC to smooth DC , those bulk capacitor power reservoirs fill juice gaps and smooth out ripple to provide rock solid DC, there are also local circuit caps to reserve power and optimally feed op amps and such, that in conjunction with electricity traveling at a speed of 300,000,000 meters per second makes your "slowed transient" claim seem to me unless i'm missing something(totally possible), a greater likelihood in my mind to a less than optimal transient response would be gear design flaws or improper installation of/or poorly built BP toroid. To be clear, i've never installed a BPS system, but i've heard head to head differences between balanced and unbalanced power, the only change being BPS, i prefered balanced at that time as it was quieter, and it seemed to increase the overall dynamic range and realism of the system, i noticed no ill effects to the transient response, i wasn't specifically listening for it, but nothing jumped out at me.
2nd thing I'd mention, and I'm more sure of as a construction contractor, counting on water pipe for grounding is a dodgy idea, the copper piping you terminate to generally connects to a relatively shallow PVC underground supply from the street, 8 out of 10 times if you dig it up, you will find its PVC, i'd recommend a properly lengthed purpose driven grounding rod to eliminate any issues.
Old 2nd May 2017
  #8
I've wired rooms with those. Copper rods at the center tap, etc. Use hospital grade outlets. WBT through Kimber makes real good ones.
Contact Ray Kimber and ask about the AC cabling. He can recommend the best wire for that as he doesn't make it himself.
www.kimberkable.com
Mount the transformer as far away from the control room as possible. Do not share that feed to air conditioners, heaters or refrigerators. Then it should be clean of interference. The benefits are your gear won't hum nor buzz as much and single coil guitars will pick up less noise. Old REP and Mix mags had articles on the subject. Also check out Sound and Video Contractor magazine. Bill Whitlock of Jensen Transformers is the expert on grounding, contact Jensen for more info on his many articles.
Old 2nd May 2017
  #9
Gear Nut
 
DeyeYguy's Avatar
 

nice, thanx for the specifics JW!
Old 4th May 2017
  #10
Lives for gear
 

IMO wooden rack create more problems than they avoid though though can work in some cases. If doing that you need to be sure that there's an air gap between each piece of gear in the rack. Otherwise it's easy to have intermittent connections between neighboring gear due to the uncertainty of screws making contact with adjacent panels, anodized surfaces that may or may not conduct to a neighboring chassis, etc. If you have iffy connections like that they can cause intermittent ground noise, maybe changing due to vibration, temperature, or touching a certain piece of gear.

You will almost never see wooden rack rails in big high end studios. There are better ways to assure a quiet system.
Old 4th May 2017
  #11
Lives for gear
 

Hi
The radiated field from a piece of power cable is largely independent of whether it is truly 'balanced' or not when considered as a 'near field' issue as it is the CURRENT balance between the live and neutral rather than the voltage balance (equality). There will be a small imbalance due to one conductor having a larger voltage on it compared top 'ground' but this extra current is only due to the cable conductor's capacitance and is considered at powerline frequency and would normally be a matter of a few milliamps at worst. You could compare the situation with 'impedance balanced' audio outputs which many others claim to work.
The impedance of a supply will increase if using a balancing transformer so you are likely to see some degradation or interaction between for example the monitor power amps when they pull a higher current when driven loud which will make the supply voltage fall a little, and always more than without a transformer.
A transformer probably will contribute to 'cleaning' the supply as massive short spike will be too 'fast' or too high a magnitude to get through the magnetic domain although decent filtering and MOV devices would be a much cheaper alternative. The increased impedance will not affect the 'transient response' of any gear as reservoir caps and regulators take care of this aspect.
Lastly, fusing for 'balanced power' where the centre tap is grounded should probably have fuses in BOTH lines, check with local wiring codes.
Ensure that all mains wiring has the live and neutral as a twisted pair throughout it's length.
Matt S
Old 5th May 2017
  #12
Gear Nut
 
DeyeYguy's Avatar
 

Quote:
Originally Posted by Matt Syson View Post
Hi
The radiated field from a piece of power cable is largely independent of whether it is truly 'balanced' or not when considered as a 'near field' issue as it is the CURRENT balance between the live and neutral rather than the voltage balance (equality). There will be a small imbalance due to one conductor having a larger voltage on it compared top 'ground' but this extra current is only due to the cable conductor's capacitance and is considered at powerline frequency and would normally be a matter of a few milliamps at worst. You could compare the situation with 'impedance balanced' audio outputs which many others claim to work.
The impedance of a supply will increase if using a balancing transformer so you are likely to see some degradation or interaction between for example the monitor power amps when they pull a higher current when driven loud which will make the supply voltage fall a little, and always more than without a transformer.
A transformer probably will contribute to 'cleaning' the supply as massive short spike will be too 'fast' or too high a magnitude to get through the magnetic domain although decent filtering and MOV devices would be a much cheaper alternative. The increased impedance will not affect the 'transient response' of any gear as reservoir caps and regulators take care of this aspect.
Lastly, fusing for 'balanced power' where the centre tap is grounded should probably have fuses in BOTH lines, check with local wiring codes.
Ensure that all mains wiring has the live and neutral as a twisted pair throughout it's length.
Matt S
Thanx for the thoughtful reply, can you explain a little further how this^ happens? There's obviously a transformer on the pole outside, and in every piece of gear we use there is a toroid or El core right, does the same degradation apply there? And wouldn't the bulk caps in the monitor PSU that follow the transformers negate any such effects? If there is any reading or papers you could link me to explaining this? i'd appreciate the info
Thanx again.
Old 5th May 2017
  #13
Lives for gear
 

Hi
You have to bear in mind that ALL cables have resistance (unless at -273 ? Centigrade where it becomes a superconductor) so as soon as ANY load is put on the socket in your studio the measured voltage will drop.
The power companies have a duty to ensure that at your property, if you pull the rated current from the supply then it will not fall outside a stated tolerance. THEY have to ensure that cables and transformers OUTSIDE your property give a sufficiently low impedance supply.

In my house when I put a kettle on which pulls 10 Amps the mains voltage drops by around 5 volts but it is on long cables over a few fields. In a city the 'regulation' (amount of drop) should be better.
Adding another transformer, even a big one with thick wire MUST increase the impedance of the supply (you can't get something for nothing, basic physics).
The capacitors and regulators in your gear ensure that unless the mains goes out of tolerance (around 10 percent) then the performance of your gear will not change. Guitar amps and the like WITHOUT internal regulation WILL change so a 400 Watt bass amp may reduce it's output level from 400 to 350 Watts (at clipping) if the mains falls by 10 percent. It would also go UP if the mains is higher than nominal.
Matt S
Old 5th May 2017
  #14
Gear Nut
 
DeyeYguy's Avatar
 

Quote:
Originally Posted by Matt Syson View Post
Hi
You have to bear in mind that ALL cables have resistance (unless at -273 ? Centigrade where it becomes a superconductor) so as soon as ANY load is put on the socket in your studio the measured voltage will drop.
The power companies have a duty to ensure that at your property, if you pull the rated current from the supply then it will not fall outside a stated tolerance. THEY have to ensure that cables and transformers OUTSIDE your property give a sufficiently low impedance supply.

In my house when I put a kettle on which pulls 10 Amps the mains voltage drops by around 5 volts but it is on long cables over a few fields. In a city the 'regulation' (amount of drop) should be better.
Adding another transformer, even a big one with thick wire MUST increase the impedance of the supply (you can't get something for nothing, basic physics).
The capacitors and regulators in your gear ensure that unless the mains goes out of tolerance (around 10 percent) then the performance of your gear will not change. Guitar amps and the like WITHOUT internal regulation WILL change so a 400 Watt bass amp may reduce it's output level from 400 to 350 Watts (at clipping) if the mains falls by 10 percent. It would also go UP if the mains is higher than nominal.
Matt S
great thanx! I wish i could find more reading on this, I've been looking, but there's not so much........
So continuing my run as a pita, i have more questions if you'll humor me, given that adding any cable or tranny adds resistance, wouldn't the addition of this BPT be the equivalent of adding a fire hose between a house hose bib and a garden hose? technically yes it adds resistance, but also capacitance, it seems V drop would be real world negligible no? Second Q would be considering a single leg 120 supply is less efficient by roughly 1/2 compared to split/2-legs carrying 240=120+120 on each @ 1/2 the v and 1/2 the I, and also considering (my understanding, i could be wrong) that the reason split phase 220v is more efficient is due to the instantaneous response due to a halved demand upon the split legs from your mains during the initiation of the load demand(in other words a faster transient response is provided over the 2 legs vs 1, this is where you supposedly save money with split 240 vs single 120, in initial start up, not in long run due to less waste). So logic would seem to dictate any V or I drop would be negated by splitting the load over 2 legs, unless of course you are seriously over tapping your drop from the utility co.... right? Now if you take those 120v legs and split them again, you have 60v per leg balanced power, the primary sides of the BP tranny are tapped split phase 120v each from the mains

also, when i consider the size of the toroids in my console PSU's and monitor amps alone, i'm thinking i'm gonna need a 3 phase commercial drop in here!
Seriously though, the amount of resistance that's added by the hundreds of pieces of gear in here that have tranny's, isn't the worry of voltage drop/resistance/transient impact being a bit dramatized? The bottom line for me is i'm trying to understand how this may hurt the performance in my studio, so far i'm really not seeing anything bad that outweighs the clear advantages of BP(especially considering my random mystery issue), but i want to try to expose and remedy any/all pitfalls before i drop the blood, sweat and tears installing all of this stuff.
hope this made sense? thanx again for your time
Old 5th May 2017
  #15
Lives for gear
 

Hi
The 'spec' claims that a nominal 120 volt OUTPUT from the transformer will drop from 120 to 115 Volts when you take 20 Amps from it. This will be over and above the amount of voltage drop the existing wiring will manage.
Any 'transient' that your power amp may take will be experienced as a much lower magnitude 'demand' from the mains as the audio current is largely supplied by the capacitors so is 'one step removed' from the mains itself as the caps 'average' the current necessary.
The whole 'marketing' thing is about over dramatisation of minor effects. The mains voltage goes up and down, as long as it is never below the minimum threshold dictated by the design all should be well.
Half the voltage equates to double the current and as power loss is current SQUARED times resistance you waste more power when running at a lower voltage. This is why overhead power lines run at 400,000 Volts or whichever.
Matt S
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