Thanks for backing me up maxlorenz
I was thinking the same thing about getting a couple of smaller toroids maybe in the 800 - 1000VA range and just using them specifically for my digital components. Right now I use my TV as the computer monitor for my desktop, even though there is no desk involved. But, my laptop is usually in a different location and I don't like running extension cords to hook all this up, it's sloppy and just plain annoying when you trip on a cord.
So, within the next few months, I think I'll get at least one more balanced toroid.
Hello AndrewT, in regards to your question on how I wired this up, it may be best for me to refer you to the spec sheet of my transformer, it's pretty much self explanatory.
My Plitron transformer, click HERE.....
OR
HERE.....
As far as what I'm doing with the caps, well, I don't really want to say just yet because I'm not done experimenting. Sorry, but I'm a little fussy like that. I'd rather spend a year to give you the right answer verses a day to feed you the wrong one. I'm not finished playing in this area so I'm not yet comfortable making any recommendations on what to use or how to use it. Instead, I just threw the idea out there like in my first post. I will say that from what I've done thus far, the caps show some very serious promise but also some danger. Getting those two to balance with one another is my goal.
My intentions for using these caps is only for my sub amp. Nothing else in my house with the exception of my kitchen oven could possibly need this much power
I don't have your typical 200 - 300 watt sub amp. I tend to think a little on the big side, so when I found the right deal, I bought an 1100 watt class A Crown amp. It's still not quite enough to drive my two 15" subs to their full potential, but it's about as much as any half sain person can tolerate. So that's my power monster.
I was thinking the same thing about getting a couple of smaller toroids maybe in the 800 - 1000VA range and just using them specifically for my digital components. Right now I use my TV as the computer monitor for my desktop, even though there is no desk involved. But, my laptop is usually in a different location and I don't like running extension cords to hook all this up, it's sloppy and just plain annoying when you trip on a cord.
So, within the next few months, I think I'll get at least one more balanced toroid.
Hello AndrewT, in regards to your question on how I wired this up, it may be best for me to refer you to the spec sheet of my transformer, it's pretty much self explanatory.
My Plitron transformer, click HERE.....
OR
HERE.....
As far as what I'm doing with the caps, well, I don't really want to say just yet because I'm not done experimenting. Sorry, but I'm a little fussy like that. I'd rather spend a year to give you the right answer verses a day to feed you the wrong one. I'm not finished playing in this area so I'm not yet comfortable making any recommendations on what to use or how to use it. Instead, I just threw the idea out there like in my first post. I will say that from what I've done thus far, the caps show some very serious promise but also some danger. Getting those two to balance with one another is my goal.
My intentions for using these caps is only for my sub amp. Nothing else in my house with the exception of my kitchen oven could possibly need this much power
I don't have your typical 200 - 300 watt sub amp. I tend to think a little on the big side, so when I found the right deal, I bought an 1100 watt class A Crown amp. It's still not quite enough to drive my two 15" subs to their full potential, but it's about as much as any half sain person can tolerate. So that's my power monster.
Here is a resource for DIY balanced power:
http://www.geocities.com/jonrisch/index.htm
There has been lot of discussion over the years at AA and a number of people have built units based on Jon Risch's recommendations. You can search the AA forum: http://www.audioasylum.com/index.html for old posts about them(mostly the "Tweak" forum as I recall).
Scott
http://www.geocities.com/jonrisch/index.htm
There has been lot of discussion over the years at AA and a number of people have built units based on Jon Risch's recommendations. You can search the AA forum: http://www.audioasylum.com/index.html for old posts about them(mostly the "Tweak" forum as I recall).
Scott
There are 2 separate issues with regards to balancing transformers -
1. Power conditioning itself. On a typical transformer power conditioner one seeks to eliminate both common and normal/transverse mode noise. Typically, this is done by one of 2 methods. The first is a grounded shield between the primary and seconday windings. This serves as a capacitive shunt for hf noise to ground. The second is split/multiple bobbins which use the physical distance between winding to minimize capacitive coupling between those windings and minimize the tranference of noise. Typically either of the above are used with appropriately configured capacitors to enhance this functionality.
2. Balanced/technical power, in which we use balanced windings to 'cancel' reactive leakage currents from grounded chassis components. On toroidal transformers, this is typically done with bi-filar wound secondaries, and if not, with great care in the winding of the secondaries.
Regarding the Plitron transformers mentioned, they do not apparently have that shielding between primary and secondary, and are not as effective as they could be in minimizing capacitive coupling between primary and secondary, and given their very high bandwidth limit their efficacy. This is evident in the Transcendant balancing power conditioner that lack that shield when compared to a purpose built balancing transformer. A good source for shielded toroids is medical isolation transformers which typically have dual 115 windings for both the primarys and secondays on Ebay. Similarly, EI transformers from Elgar, MGE, Topaz, Xentek have shielding and very low capacitive coupling are also available on Ebay. Used in N.A., these require a downrating of capacity as the 115/120v windings are fed/produce 60v. These transformers work without downrating in 220-240vac mains environments, but unfortauneately, shipping costs are quite high.
The efficacy of reactive leakage cancellation is compromised to the extent of misbalancing of non bifilar wound secondaries.
Personally, in my noisey NYC environment, it is the power conditioning that provides the bulk of the subjective benefits. This can be tested subjectively by connecting a spdt, center off, switch to the ground. In the up position, the ground is connected to the center tap of the secondary windings, providing balanced/technical power. In the down position, the ground is connected to one side of the secondary winding, rebonding ground to neutral, the typical isolation transformer configuration, and in the center off position, the ground is connected to nothing, providing floating 'isolated' power, as is typically found in hospital environments.
It allways helps to empirically verify one's assumptions.
FWIW
1. Power conditioning itself. On a typical transformer power conditioner one seeks to eliminate both common and normal/transverse mode noise. Typically, this is done by one of 2 methods. The first is a grounded shield between the primary and seconday windings. This serves as a capacitive shunt for hf noise to ground. The second is split/multiple bobbins which use the physical distance between winding to minimize capacitive coupling between those windings and minimize the tranference of noise. Typically either of the above are used with appropriately configured capacitors to enhance this functionality.
2. Balanced/technical power, in which we use balanced windings to 'cancel' reactive leakage currents from grounded chassis components. On toroidal transformers, this is typically done with bi-filar wound secondaries, and if not, with great care in the winding of the secondaries.
Regarding the Plitron transformers mentioned, they do not apparently have that shielding between primary and secondary, and are not as effective as they could be in minimizing capacitive coupling between primary and secondary, and given their very high bandwidth limit their efficacy. This is evident in the Transcendant balancing power conditioner that lack that shield when compared to a purpose built balancing transformer. A good source for shielded toroids is medical isolation transformers which typically have dual 115 windings for both the primarys and secondays on Ebay. Similarly, EI transformers from Elgar, MGE, Topaz, Xentek have shielding and very low capacitive coupling are also available on Ebay. Used in N.A., these require a downrating of capacity as the 115/120v windings are fed/produce 60v. These transformers work without downrating in 220-240vac mains environments, but unfortauneately, shipping costs are quite high.
The efficacy of reactive leakage cancellation is compromised to the extent of misbalancing of non bifilar wound secondaries.
Personally, in my noisey NYC environment, it is the power conditioning that provides the bulk of the subjective benefits. This can be tested subjectively by connecting a spdt, center off, switch to the ground. In the up position, the ground is connected to the center tap of the secondary windings, providing balanced/technical power. In the down position, the ground is connected to one side of the secondary winding, rebonding ground to neutral, the typical isolation transformer configuration, and in the center off position, the ground is connected to nothing, providing floating 'isolated' power, as is typically found in hospital environments.
It allways helps to empirically verify one's assumptions.
FWIW
In regards to a balanced power supply; here in the U.S. we have balanced 220V coming into our homes. From there it is split into 2 single ended legs to power our apliances and lights. Would there be a benefit to using 220V instead of a high priced power conditioner. I have some components that have multi voltage transformers and since I own my home, wiring a dedicated outlet for my stereo is not an issue.
If it's safe and legal for you to do so, definitely try it. Running off twice the voltage the equipment, drawing only half the current, means at least 6dB more tolerance to noise etc. on the line.
Results are likely to still depend on the current capability of the intermediate transformer just as discussed above though.
Results are likely to still depend on the current capability of the intermediate transformer just as discussed above though.
balanced power concerns
Hello Don Nebel You can certainly try that and I'm sure you will get very good results. I personally though would use a transformer to do the job only because you get the added benefit of slight noise reduction along with slight regulation. I know I know, theory says different, but I don't live in theory. In reality, almost anything you place inline with the load, will result in some attenuation of some kind. Sometimes, this is a good thing, sometimes not so good. But for this topic, the attenuation factor inherent of transformers, is a fairly good thing. But try your 220 idea and let me know how it goes.
Hello pmkap
I found your post quite interesting, however, I have some questions and concerns. In power conditioning, we all would love to ELIMINATE noise of all kinds, however, as I'm sure you already know, total elimination is an impossibility. At best, we can only hope for sever attenuation. Since all thing analog and digital for that matter is essentially based on a curve, all we can do in reality is manipulate that curve. We can change phase angles, boost or reduce DB's in various frequencies, manipulate voltage and amperage in a multitude of different ways, but to stop anyone of them without stopping them all, well, mankind is pretty smart, but it's not yet that smart.
I totally agree with you on having a shield between the primary and secondary of a transformer, but only when dealing with a conventional square transformer. I'm sure it has a very technical name, but I don't know what it is. In the world of toroids however, stray magnetic fields are a minimal concern at best simply due to the inherent nature of the toroid which is to contain the magnetics within it's self. They are really quite good at this, far better then a square transformer.
The transformer I use which I posted a link to, has a shield, but it's external, rather then internal. So what difference does it make? As I said in my first post, I did my home work before making my decision. When we look at what classifies a shield, it is either a barrier to contain something internal, or a barrier to resist something external. My transformer has a Faraday shield since it's encased in an aluminum housing, the transformer with housing is then placed inside a rather large aluminum enclosure which is grounded and serves as a second Faraday shield. So, due to the fact that toroids are so good at containing stray magnetics and that my toroid is doubly shielded, I have my desktop computer sitting directly on top of this thing. It's not there cause I'm cocky, it's only there since it wont fit anywhere else in my living room. As I said earlier, I use my TV as my computer monitor, so naturally the computer has to be very close to the TV for hook up.
Now I have only looked at this shielding from a magnetics or energy point of view, the capacitive coupling you spoke of, I can't picture this. The toroid, or any transformer for that matter will have X amount of capacitance with X amount of inductance simply due to the long length of wire used and being wrapped in a circle. Could you please explain the capacitance scenario you spoke of?
I am using capacitors on 3 of my 5 secondaries wired in parallel. I should have mentioned this earlier and maybe I did but I can't remember. What I'm doing with the caps is power factor correction. I have finished the math now and tested this to a great degree and now feel comfortable talking about it. My power factor caps equal 3.3 KVAR. I run my transformer currently on a 15 amp circuit. Each of the 5 outputs on the secondaries can support a little over 4 amps. I have 2 outputs wired in parallel feeding 3 GFCI receptacles which gives me a little over 8 amps worth of current capacity. I then use my remaining 3 outputs again wired in parallel to feed one more GFCI receptacle and this one gives me a little over 12 amps capacity. This one has the power factor correction. Keep in mind all this runs on a 15 amp main feed circuit. I don't know where the PFC outlet would peak, but it's designed for 20 amp capacity with PFC. I have measured spikes on this outlet of 15.35 amps using multiple loads while using the other 3 outlets as normal. Now, in theory, this shouldn't be possible since I only have 15 amps available, but because of the PFC on one outlet, I have been able to briefly exceed wall outlet capacity which was my goal from the beginning. Now I can run all of my equipment on a 15 amp circuit but get the added capacity like I was using a 20 amper. It's very simple to do, I know, but it's still impressive and I can't help but smile when I think about it. What can I say, small minds amuse easily
Your right though, my Plitron transformer does not have the shield between the primary and secondary, but as I explained earlier, it doesn't really need it to do a truly excellent job like it's doing for me. Yes, there are dozens of other manufactures out there that make excellent transformers. But I like Plitron personally and I love toroids and Plitron gave me what I wanted and needed for less money then other manufactures. so that's why I went with them. Also, what I bought, you can't find on ebay but your welcome to try. I gave up the ebay search after about a year cause I just couldn't find what I wanted. My transformer is high bandwidth but it's not inefficient buy any stretch of the imagination. This thing is 96% efficient and according to my test results, it draws 0.23 amps at idle for a 2400 VA transformer. These are honestly the best numbers I can recall seeing of any transformer that I've tested. The iso transformers I used before this paled in comparison for less then half the capacity.
I like your idea for running a test with a switch, any non believers of balanced power out there should definitely give that a try. However, they might also try the same thing on just lifting the ground so as to eliminate any potential ground loop interference. Prior to using balanced power, I just about went nuts trying to get rid of this annoying hum I had coming through my subs. Ultimately, I had to lift the ground on the amp it's self to stop the noise. That solved the problem, but, I don't consider that success since I was never able to determine the actual cause of the problem, it's more like a band aid then a solution. But it was interesting just the same.
I gotta tell ya, I'm not quite sure how to take the last part of your post.
I don't know about everyone else here, but I assume nothing, ever! I test and prove, then re-test and re-prove, I fail, then succeed so I can start again. This is how I learn and only once I have learned, only then do I open my mouth to try and help others.
Hello Don Nebel You can certainly try that and I'm sure you will get very good results. I personally though would use a transformer to do the job only because you get the added benefit of slight noise reduction along with slight regulation. I know I know, theory says different, but I don't live in theory. In reality, almost anything you place inline with the load, will result in some attenuation of some kind. Sometimes, this is a good thing, sometimes not so good. But for this topic, the attenuation factor inherent of transformers, is a fairly good thing. But try your 220 idea and let me know how it goes.
Hello pmkap
I found your post quite interesting, however, I have some questions and concerns. In power conditioning, we all would love to ELIMINATE noise of all kinds, however, as I'm sure you already know, total elimination is an impossibility. At best, we can only hope for sever attenuation. Since all thing analog and digital for that matter is essentially based on a curve, all we can do in reality is manipulate that curve. We can change phase angles, boost or reduce DB's in various frequencies, manipulate voltage and amperage in a multitude of different ways, but to stop anyone of them without stopping them all, well, mankind is pretty smart, but it's not yet that smart.
I totally agree with you on having a shield between the primary and secondary of a transformer, but only when dealing with a conventional square transformer. I'm sure it has a very technical name, but I don't know what it is. In the world of toroids however, stray magnetic fields are a minimal concern at best simply due to the inherent nature of the toroid which is to contain the magnetics within it's self. They are really quite good at this, far better then a square transformer.
The transformer I use which I posted a link to, has a shield, but it's external, rather then internal. So what difference does it make? As I said in my first post, I did my home work before making my decision. When we look at what classifies a shield, it is either a barrier to contain something internal, or a barrier to resist something external. My transformer has a Faraday shield since it's encased in an aluminum housing, the transformer with housing is then placed inside a rather large aluminum enclosure which is grounded and serves as a second Faraday shield. So, due to the fact that toroids are so good at containing stray magnetics and that my toroid is doubly shielded, I have my desktop computer sitting directly on top of this thing. It's not there cause I'm cocky, it's only there since it wont fit anywhere else in my living room. As I said earlier, I use my TV as my computer monitor, so naturally the computer has to be very close to the TV for hook up.
Now I have only looked at this shielding from a magnetics or energy point of view, the capacitive coupling you spoke of, I can't picture this. The toroid, or any transformer for that matter will have X amount of capacitance with X amount of inductance simply due to the long length of wire used and being wrapped in a circle. Could you please explain the capacitance scenario you spoke of?
I am using capacitors on 3 of my 5 secondaries wired in parallel. I should have mentioned this earlier and maybe I did but I can't remember. What I'm doing with the caps is power factor correction. I have finished the math now and tested this to a great degree and now feel comfortable talking about it. My power factor caps equal 3.3 KVAR. I run my transformer currently on a 15 amp circuit. Each of the 5 outputs on the secondaries can support a little over 4 amps. I have 2 outputs wired in parallel feeding 3 GFCI receptacles which gives me a little over 8 amps worth of current capacity. I then use my remaining 3 outputs again wired in parallel to feed one more GFCI receptacle and this one gives me a little over 12 amps capacity. This one has the power factor correction. Keep in mind all this runs on a 15 amp main feed circuit. I don't know where the PFC outlet would peak, but it's designed for 20 amp capacity with PFC. I have measured spikes on this outlet of 15.35 amps using multiple loads while using the other 3 outlets as normal. Now, in theory, this shouldn't be possible since I only have 15 amps available, but because of the PFC on one outlet, I have been able to briefly exceed wall outlet capacity which was my goal from the beginning. Now I can run all of my equipment on a 15 amp circuit but get the added capacity like I was using a 20 amper. It's very simple to do, I know, but it's still impressive and I can't help but smile when I think about it. What can I say, small minds amuse easily
Your right though, my Plitron transformer does not have the shield between the primary and secondary, but as I explained earlier, it doesn't really need it to do a truly excellent job like it's doing for me. Yes, there are dozens of other manufactures out there that make excellent transformers. But I like Plitron personally and I love toroids and Plitron gave me what I wanted and needed for less money then other manufactures. so that's why I went with them. Also, what I bought, you can't find on ebay but your welcome to try. I gave up the ebay search after about a year cause I just couldn't find what I wanted. My transformer is high bandwidth but it's not inefficient buy any stretch of the imagination. This thing is 96% efficient and according to my test results, it draws 0.23 amps at idle for a 2400 VA transformer. These are honestly the best numbers I can recall seeing of any transformer that I've tested. The iso transformers I used before this paled in comparison for less then half the capacity.
I like your idea for running a test with a switch, any non believers of balanced power out there should definitely give that a try. However, they might also try the same thing on just lifting the ground so as to eliminate any potential ground loop interference. Prior to using balanced power, I just about went nuts trying to get rid of this annoying hum I had coming through my subs. Ultimately, I had to lift the ground on the amp it's self to stop the noise. That solved the problem, but, I don't consider that success since I was never able to determine the actual cause of the problem, it's more like a band aid then a solution. But it was interesting just the same.
I gotta tell ya, I'm not quite sure how to take the last part of your post.
I don't know about everyone else here, but I assume nothing, ever! I test and prove, then re-test and re-prove, I fail, then succeed so I can start again. This is how I learn and only once I have learned, only then do I open my mouth to try and help others.
If you're looking for a isolation transformer in the 250VA range take a look at the Lundahl 1655
mains isolation transformer. It is constructed in the same manner as their tube outptut transformers, with an airgap. The airgap eliminates the DC offset on the mains.
I build a mains distribution block with it:
Clean Mains
The improved ground connection reduces the noise on the output of my Benchmark DAC1 by 10-20dB.
The Lundahl reduces common-mode noise by about 20dB.
mains isolation transformer. It is constructed in the same manner as their tube outptut transformers, with an airgap. The airgap eliminates the DC offset on the mains.
I build a mains distribution block with it:
Clean Mains
The improved ground connection reduces the noise on the output of my Benchmark DAC1 by 10-20dB.
The Lundahl reduces common-mode noise by about 20dB.
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