Would you kindly help this poor lost boy to design and build the step up transformer and DC transformer for the Martin Logan Monolith III panels. This needs to be the lowest cost set up. Later I will save up to make a better one.
I will use an active x-over with a high pass of 140Hz so this setup needs to be able to handle that.
The step up ratio needs to be 1:50 and the DC voltage to the diaphragm is 3,200 volts.
1) which transformers should I buy (i.e. what should the X-former specs be).
2) wiring instructions, diagram or schematics
If possible, I'd love to find transformers that ship from the USA such as from Parts Express: the #1 source for audio, video & speaker building components , Mouser Electronics - Electronic Components Distributor , Invalid Request , Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more or any other commonly known place like that.
On a scale of one to ten, my schematic reading ability is about a four point five (4.5)
If y'all can get someone like me through this with success, it would be pretty awesome and I'd have to say that the www.diyaudio.com forums are amazing. 
Kindest thanks,
Eddie
I will use an active x-over with a high pass of 140Hz so this setup needs to be able to handle that.
The step up ratio needs to be 1:50 and the DC voltage to the diaphragm is 3,200 volts.
1) which transformers should I buy (i.e. what should the X-former specs be).
2) wiring instructions, diagram or schematics
If possible, I'd love to find transformers that ship from the USA such as from Parts Express: the #1 source for audio, video & speaker building components , Mouser Electronics - Electronic Components Distributor , Invalid Request , Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more or any other commonly known place like that.
On a scale of one to ten, my schematic reading ability is about a four point five (4.5)
If y'all can get someone like me through this with success, it would be pretty awesome and I'd have to say that the www.diyaudio.com forums are amazing.
Kindest thanks,
Eddie
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A good place to start is with CharlieM's interface setup if not get some older used bigger Acoustat interfaces.
I see you have started a new thread on this subject, There is no need to do that.
Jazzman's DIY Electrostatic Loudspeaker Page: The Electronics Package
I don't know what the specs to the Monolith's are or what there designed frequency range is.
With common power toroids you would be okay as long as you stay above a crossover frequency of about 360Hz.
If you need to go lower (down to 40Hz to 80Hz then you would need to either have to use more Toroid's (8 or more) or get a used Acoustat interface as I had already mentioned.
8 cores will get you to the 150Hz to 200Hz range okay with a 1:80 transformation ratio as they are rather large panels.
More info about your panels and exactly what you have to work with would greatly help to figure out exactly what would work, Mainly what is their total capacitance and your intended design setup?
Are you planning a hybrid system using some woofers?
jer
P.S. Do Read up on the latest threads concerning more info on transformer setups.
I have explained many times in great detail as to what and how this things work and their required parameters.
But if there is anything that you don't understand, Please DO feel free to ask, and I or anyone else will gladly help too explain for you in greater detail.
They are a bit of a mystery at First, But they are very simple really once you get to understanding the workings of the Step-up transformer and how it relates to an ESL driver.
I see you have started a new thread on this subject, There is no need to do that.
Jazzman's DIY Electrostatic Loudspeaker Page: The Electronics Package
I don't know what the specs to the Monolith's are or what there designed frequency range is.
With common power toroids you would be okay as long as you stay above a crossover frequency of about 360Hz.
If you need to go lower (down to 40Hz to 80Hz then you would need to either have to use more Toroid's (8 or more) or get a used Acoustat interface as I had already mentioned.
8 cores will get you to the 150Hz to 200Hz range okay with a 1:80 transformation ratio as they are rather large panels.
More info about your panels and exactly what you have to work with would greatly help to figure out exactly what would work, Mainly what is their total capacitance and your intended design setup?
Are you planning a hybrid system using some woofers?
jer
P.S. Do Read up on the latest threads concerning more info on transformer setups.
I have explained many times in great detail as to what and how this things work and their required parameters.
But if there is anything that you don't understand, Please DO feel free to ask, and I or anyone else will gladly help too explain for you in greater detail.
They are a bit of a mystery at First, But they are very simple really once you get to understanding the workings of the Step-up transformer and how it relates to an ESL driver.
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Below are the specs of the Monolith III from the manual...you only need to look at page five since all the specs they provide are there.
https://www.dropbox.com/s/63wkl8eq9omx5hz/manual_monolith_iii.pdf
The step up ratio needs to be 1:50 not 1:80 (i.e. it will have to be 1:50 no other ratio will be used). The high pass x-over point needs to be 140Hz (no other x-over point will be used ONLY 140Hz).
Thanks so much for your help
Eddie
https://www.dropbox.com/s/63wkl8eq9omx5hz/manual_monolith_iii.pdf
The step up ratio needs to be 1:50 not 1:80 (i.e. it will have to be 1:50 no other ratio will be used). The high pass x-over point needs to be 140Hz (no other x-over point will be used ONLY 140Hz).
Thanks so much for your help
Eddie
Then use 8 9V/115 transformers wired for 18v/920v this will get you to 1:51.1 and down to 150Hz at 54Vrms.
I don't think 10hz will make to much of a difference, although it is right at the edge of core saturation.
AN-0209 - 25VA 9V Transformer - AnTek Products Corp
Using 1:80 will up your sensitivity but may drop your impedance quite low considering their size and amount of capacitance they may have.
At $88 a panel isn't to bad but I have seen some complete Acoustat interfaces go for not much more than that.
If you limit your input voltage to 27Vrms you might be able to get away with using only 4 cores per panel wired as 9V/460v.
For 140HZ operation you would have to drop your input voltage to 50.4Vrms and 25.2Vrms respectively.
That would be right at the edge of saturation and should consider another 5% to 10% drop of input voltage in order to not get any saturation if you set your crossover at 140Hz.
The transformers are designed for 50hz operation, so this is the lowest factor you have to work with when calculating your saturation point per voltage input.
jer
P.S I hope that you have a big amp that can swing such a high voltage with only a 1:51.1 ratio.
This would only be 2500Vrms and you would only need 31.25Vrms to get to the level with a 1:80 step-up ratio.
Providing the amp can supply the current.
If you have a capacitance meter you can measure the capacitance of the panel and that would give you an idea as to what your final impedance may be not including the transformers capacitance's.
I don't think 10hz will make to much of a difference, although it is right at the edge of core saturation.
AN-0209 - 25VA 9V Transformer - AnTek Products Corp
Using 1:80 will up your sensitivity but may drop your impedance quite low considering their size and amount of capacitance they may have.
At $88 a panel isn't to bad but I have seen some complete Acoustat interfaces go for not much more than that.
If you limit your input voltage to 27Vrms you might be able to get away with using only 4 cores per panel wired as 9V/460v.
For 140HZ operation you would have to drop your input voltage to 50.4Vrms and 25.2Vrms respectively.
That would be right at the edge of saturation and should consider another 5% to 10% drop of input voltage in order to not get any saturation if you set your crossover at 140Hz.
The transformers are designed for 50hz operation, so this is the lowest factor you have to work with when calculating your saturation point per voltage input.
jer
P.S I hope that you have a big amp that can swing such a high voltage with only a 1:51.1 ratio.
This would only be 2500Vrms and you would only need 31.25Vrms to get to the level with a 1:80 step-up ratio.
Providing the amp can supply the current.
If you have a capacitance meter you can measure the capacitance of the panel and that would give you an idea as to what your final impedance may be not including the transformers capacitance's.
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If you used these 15V transformers this would get you to 1:61.33. and a edge of saturation voltage of 42Vrms at 140Hz for 2575Vrms for the panel.
I don't know what the limits are of what those panels can do, But with a 5Kv bias it should be quite loud at 3641Vpeak (7280Vp-p)!!
AN-0215 - 25VA 15V Transformer - AnTek Products Corp
jer
I don't know what the limits are of what those panels can do, But with a 5Kv bias it should be quite loud at 3641Vpeak (7280Vp-p)!!
AN-0215 - 25VA 15V Transformer - AnTek Products Corp
jer
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The ML Monolith-III transformers are just the regular EI-core style that have single primaries with dual secondary's which can be arranged for a 1:50, 1:75 or 1:100 ratio for various models. You can purchase these transformers from ML part number: F9283 which sell for $359.13ea. plus shipping and the wiring schematic for the 1:50 ratio is listed below.
I did make many different esl transformers in the past but i stopped making them. Nobody is interested in a quality transformers, most people are interested in cheap transformers.
For €75,- or less you can not make a good esl-transformer unless 1000 or more people buy. What i have seen so far no "standard" transformer is good enough. Specially for full-range.
For €75,- or less you can not make a good esl-transformer unless 1000 or more people buy. What i have seen so far no "standard" transformer is good enough. Specially for full-range.
I have recently heard that most of the "standard" transformers result in a decreased frequency response in the high frequencies....something to do with the core material?
What type of core should I look for ... or which specific transformer will NOT compromise the high frequencies that are above 18Khz ?
They recommended the following type of "Audio" transformer.
Standard Range
are there other sources of good "audio" grade transformers that aren't so expensive? Or at least one that is close to being "Audio" grade with minimal compromise in the high highs?
Eddie
What type of core should I look for ... or which specific transformer will NOT compromise the high frequencies that are above 18Khz ?
They recommended the following type of "Audio" transformer.
Standard Range
are there other sources of good "audio" grade transformers that aren't so expensive? Or at least one that is close to being "Audio" grade with minimal compromise in the high highs?
Eddie
Hmmmm.....UPS to me would be $400 to $600 !!!!
I could drive that myself for less than 1/2 to 1/4 that !!
Here are a few things to consider if you want to create your own step-up transformer and lots of other good info in this thread as well,
http://www.diyaudio.com/forums/planars-exotics/246137-esl-transformer-question.html#post3771882
jer
I could drive that myself for less than 1/2 to 1/4 that !!
Here are a few things to consider if you want to create your own step-up transformer and lots of other good info in this thread as well,
http://www.diyaudio.com/forums/planars-exotics/246137-esl-transformer-question.html#post3771882
jer
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I don't know if the dayton wright are really full-range.
I look today at the Plitron toroid 1:75 transformers, also "full-range" but with 0,2 (+0,82 serie resistor) Ohm at 20kHz i can't call that full-range under normal home conditions.
I look today at the Plitron toroid 1:75 transformers, also "full-range" but with 0,2 (+0,82 serie resistor) Ohm at 20kHz i can't call that full-range under normal home conditions.
There you go...Perfect !!!!
And full range too !!!
jer
From all of the specs I have read on them they are, and go down to at least 40hz,
DW Electrostatic Speakers XG-8 Mk III
FWIW
jer
DW Electrostatic Speakers XG-8 Mk III
FWIW
jer
What is the transformer impedance vs frequency response?
From all of the specs I have read on them they are, and go down to at least 40hz,
DW Electrostatic Speakers XG-8 Mk III
FWIW
jer
Your guess is as good as mine, I didn't design it !!
It would be nice if someone took the time to measure such transformers for the DIY community.
But I am sure that if the shipping doesn't kill ya, it may very well be a better alternative to stacking up 8 power toroids that will only get you down to 140Hz for 42Vrms.
The impedance and FR is specified on the web site as 32hz to 24Khz +/- 4db at 80Kohms to an amplifier rating of as low as 4 ohms nominal, from a minimum of 60watts to a maximum of 2400watts!
I would expect that out of 39 lbs of iron.
FWIW
jer
It would be nice if someone took the time to measure such transformers for the DIY community.
But I am sure that if the shipping doesn't kill ya, it may very well be a better alternative to stacking up 8 power toroids that will only get you down to 140Hz for 42Vrms.
The impedance and FR is specified on the web site as 32hz to 24Khz +/- 4db at 80Kohms to an amplifier rating of as low as 4 ohms nominal, from a minimum of 60watts to a maximum of 2400watts!
I would expect that out of 39 lbs of iron.
FWIW
jer
I designed (esl)transformers and i would love to see the real specifications before i say anything about it. Till so far i have not enough information.
Your guess is as good as mine, I didn't design it !!
It would be nice if someone took the time to measure such transformers for the DIY community.
But I am sure that if the shipping doesn't kill ya, it may very well be a better alternative to stacking up 8 power toroids that will only get you down to 140Hz for 42Vrms.
The impedance and FR is specified on the web site as 32hz to 24Khz +/- 4db at 80Kohms to an amplifier rating of as low as 4 ohms nominal, from a minimum of 60watts to a maximum of 2400watts!
I would expect that out of 39 lbs of iron.
FWIW
jer
when you say that in order to get a lower frequency response down to ~150Hz instead of only down to ~300Hz (those numbers are just examples) that it may be necessary to use 4 transformers per ESL instead of 2 per ESL...would you please explain that father.
For example, do you take 2 of the transformers and hook them up together in parallel and wire the other 2 in parallel also and then wire one of those paralleled pairs in series with the other paralleled pair?
I guess I need help understanding how the wiring would be done if I double the number of xformers in a given design.
For example, do you take 2 of the transformers and hook them up together in parallel and wire the other 2 in parallel also and then wire one of those paralleled pairs in series with the other paralleled pair?
I guess I need help understanding how the wiring would be done if I double the number of xformers in a given design.
Yes, it would take twice as many transformers to get down to 1/2 the frequency in general.
I explained this in more greater detail in your other thread here,
http://www.diyaudio.com/forums/planars-exotics/246137-esl-transformer-question-2.html#post3794640
Yes, your second question is correct almost, There are several configurations that you can use to achieve the same ratio, but there are a only few that will give you the best overall performance as well, Those reasoning's I had touched on in the other thread.
The configuration that I was referring to is like this one, But only using 8 of the 15V transformers I had mentioned earlier,
http://www.diyaudio.com/forums/planars-exotics/246137-esl-transformer-question.html#post3771712
This would give you 920V/15V at 1:61.33 step up ratio and be able to handle 140Hz at 42Vrms as well as keep the transformers self capacitance low.
Here is another good recent discussion,
http://www.diyaudio.com/forums/planars-exotics/233008-esl-hybrid.html#post3432129
If you were to limit your lowest crossover frequency of interest to above 300hz then you would not need as many cores.
You may be able to get by using only 2 cores but 4 would give you better performance out of your amplifier for reasons I have stated in the other thread.
jer
I explained this in more greater detail in your other thread here,
http://www.diyaudio.com/forums/planars-exotics/246137-esl-transformer-question-2.html#post3794640
Yes, your second question is correct almost, There are several configurations that you can use to achieve the same ratio, but there are a only few that will give you the best overall performance as well, Those reasoning's I had touched on in the other thread.
The configuration that I was referring to is like this one, But only using 8 of the 15V transformers I had mentioned earlier,
http://www.diyaudio.com/forums/planars-exotics/246137-esl-transformer-question.html#post3771712
This would give you 920V/15V at 1:61.33 step up ratio and be able to handle 140Hz at 42Vrms as well as keep the transformers self capacitance low.
Here is another good recent discussion,
http://www.diyaudio.com/forums/planars-exotics/233008-esl-hybrid.html#post3432129
If you were to limit your lowest crossover frequency of interest to above 300hz then you would not need as many cores.
You may be able to get by using only 2 cores but 4 would give you better performance out of your amplifier for reasons I have stated in the other thread.
jer
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i been reading through the posts y'all suggested and indeed it's helped me make some progress but I'm nowhere close yet. Is there a concise way to explain the formula or to list the parameters that are used to estimate (or calculate) the frequency response of a step up transformer (or a set of transformers wired together). In other words, when I thumbing through a product catalog that offers thousands of transformers, what do i need to look for to help me determine what the frequency response would be of the one i'm looking at or how to determine how many of them I would need.
The following hypo might help me. What would the hypothetical specs be of a single transformer that can achieve the same frequency response as eight (8) combined transformers? The frequency response I seek is ~150Hz to 20,000Hz. In other words, if I can achieve that frequency response with eight transformers per panel, what kind of hypothetical transformer can achieve the same performance with just a single transformer?
I'm just trying to consolidate the various readings into one contiguous coherent thought.
The following hypo might help me. What would the hypothetical specs be of a single transformer that can achieve the same frequency response as eight (8) combined transformers? The frequency response I seek is ~150Hz to 20,000Hz. In other words, if I can achieve that frequency response with eight transformers per panel, what kind of hypothetical transformer can achieve the same performance with just a single transformer?
I'm just trying to consolidate the various readings into one contiguous coherent thought.
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