Design Me A Transformer, I Will Pay

On Fri, 6 Sep 2019 11:33:37 -0700 (PDT), jurb6006@gmail.com wrote:

>I have tried to figure out how to do this but my education lacks. What do people like me do when they need something done they can't do ? Pay someone. 
>
>I need an audio transformer, actually a center tapped choke. I can't seem to source it so custom mad, oh well. You get what you pay for. 
>
>This has to be high quality for audio, not saturate or any of that and I need a low DCR. 
>
>This is the configuration;
<snip>
>
>The load consider to be four ohms from end to end. I need to push +30 volts into one end and have -30 volts come out the other end, able to feed low impedance. I need it to do that efficiently at least from 20-20,000. 
>
>How much ? Or do you want in on the deal ? They will go for like two grand so just 5% is a Cnote. If you're any kind of an audiophile I could just give you one of these amps. There really is nothing like them on the market. 
>
>If you can't get my email with your client software it is JURB6006 at gmail, and of course dot com. You can reply here, just how much do you want to do this ? I need wire size, number of turns and the core specifics. I know the basics about transformers but this is beyond me. Frequency response flat and all that, I have no clue. An RF transformer I could tune with caps, a power transformer, actually I tried using one once and the performance was not good. 
>
>I used to do this scrapping tube amps that had 4 and 16 ohm outputs with good results. The 4 is the center tap and the 0 and 16 are the ends. thing is if I go too high in power I am inducing a hell of alot of voltage into the "primary" which isn't really anymore. But it can arc and break down insulation. I would consider them but for that, I would need them in the higher wattage range. Without the "primary" it should save money and weight. 
>
>I have it mostly figured out except this. Well and one thing i want to do to the tone controls, at the highest turnover frequency the treble will have +/- 20dB range, if the turnover is lowered by the control to boost more of the spectrum I want to decrease the range so people don't blow their tweeters. I might make it switchable - "treble protection". Other than that over half the math is done and I am all the way back to the tone board, it is designed but I want a differential drive to the output circuit. 
>
>Interested in this ? I am not hard to find.

You might review 70V/100v public address distribution transformers. 
These may have multiple windings for separate loads, that could 
be reconfigured as autotxf.

Higher powers might be a stretch.

RL

legg <legg@nospam.magma.ca> wrote in
news:th2fnel819q7o2rrm1r7lr67mqkt43arle@4ax.com: 

> On Fri, 6 Sep 2019 11:33:37 -0700 (PDT), jurb6006@gmail.com wrote:
> 
>>I have tried to figure out how to do this but my education lacks.
>>What do people like me do when they need something done they can't
>>do ? Pay someone. 
>>
>>I need an audio transformer, actually a center tapped choke. I
>>can't seem to source it so custom mad, oh well. You get what you
>>pay for. 
>>
>>This has to be high quality for audio, not saturate or any of that
>>and I need a low DCR. 
>>
>>This is the configuration;
> <snip>
>>
>>The load consider to be four ohms from end to end. I need to push
>>+30 volts into one end and have -30 volts come out the other end,
>>able to feed low impedance. I need it to do that efficiently at
>>least from 20-20,000. 
>>
>>How much ? Or do you want in on the deal ? They will go for like
>>two grand so just 5% is a Cnote. If you're any kind of an
>>audiophile I could just give you one of these amps. There really
>>is nothing like them on the market. 
>>
>>If you can't get my email with your client software it is JURB6006
>>at gmail, and of course dot com. You can reply here, just how much
>>do you want to do this ? I need wire size, number of turns and the
>>core specifics. I know the basics about transformers but this is
>>beyond me. Frequency response flat and all that, I have no clue.
>>An RF transformer I could tune with caps, a power transformer,
>>actually I tried using one once and the performance was not good. 
>>
>>I used to do this scrapping tube amps that had 4 and 16 ohm
>>outputs with good results. The 4 is the center tap and the 0 and
>>16 are the ends. thing is if I go too high in power I am inducing
>>a hell of alot of voltage into the "primary" which isn't really
>>anymore. But it can arc and break down insulation. I would
>>consider them but for that, I would need them in the higher
>>wattage range. Without the "primary" it should save money and
>>weight. 
>>
>>I have it mostly figured out except this. Well and one thing i
>>want to do to the tone controls, at the highest turnover frequency
>>the treble will have +/- 20dB range, if the turnover is lowered by
>>the control to boost more of the spectrum I want to decrease the
>>range so people don't blow their tweeters. I might make it
>>switchable - "treble protection". Other than that over half the
>>math is done and I am all the way back to the tone board, it is
>>designed but I want a differential drive to the output circuit. 
>>
>>Interested in this ? I am not hard to find.
> 
> You might review 70V/100v public address distribution
> transformers. These may have multiple windings for separate loads,
> that could be reconfigured as autotxf.
> 
> Higher powers might be a stretch.
> 
> RL
> 

  The old transformer coupled PA systems?  Yeah...  Isn't that 70.7 
Volts?  Hehehe...

  Yes most do have multiple windings.  Some have several.

On 9/9/2019 11:44 PM, jlarkin@highlandsniptechnology.com wrote:
> On Mon, 9 Sep 2019 21:08:16 -0700 (PDT), Phil Allison
> <pallison49@gmail.com> wrote:
> 
>> jla...@highlandsniptechnology.com wrote:
>>
>> -----------------------------------------
>>
>>>
>>>> Winfield Hill making an utter ASS of himself again wrote:
>>>> -------------------------------------------------------
>>>>>
>>>>> Phil Allison wrote drivel
>>>>>
>>>>
>>>> ** My complaints were rock solid.
>>>>
>>>> You made no attempt to reply to any of them.
>>>>
>>>> One would have to be forgiven for declaring you to be a pompous ass.
>>>>
>>>>
>>>>>   Give it a rest Phil.
>>>>
>>>>
>>>> ** FFS never post such absurdities about audio again.
>>>>
>>>>    Or else the gloves come off.
>>>>
>>>>
>>> Phil, have you designed any interesting audio power amps? Please post
>>> something.
>>>
>>>
>>
>>
>> ** This is not any kind of reply to my post.
>>
>> Not able or willing to post a real reply, the totally disingenuous prick goes on a trolling expedition.
>>
>> FYI: Since I am not a fish, I will not be biting.
>>
>> Larkin just keeps on proving what a piece of low life scum he is.
>>
>> His rampant autism is no excuse for being such a total ass.
>>
>>
> 
> Nothing to show us?
> 

Of course not. He has probably never designed an amplifier. He is just a 
repair service.

On 9/8/2019 7:36 PM, Phil Allison wrote:
> John Shithead is a TROLL wrote:
> 
> ----------------------------------
> 
>>>>>>
>>>>
>>>> ** Utter nonsense.
>>
>>>> It's a wide band audio power tranny, not a SMPS.
>>
>> Using .029 thick steel will not be good.
>>
> 
> ** Explain how million of high quality audio output trannys use regular steel laminations. I will not hold my breath waiting.

Please define "regular steel laminations". What thickness of laminations 
and what composition of steel? If you don't know these things then 
you're just spouting nonsense and insulting other posters.

>    My point about SMPS has gone way over your head.

This is not a SMPS transformer, so your point has missed the mark.

> 
> 
>>
>>>>> You will need to have enough laminations
>>>>> (core) to not saturate at 20Hz.
>>>>
>>>> ** Right, full power at 20Hz happens all the time in audio ...
>>>>

>>>>> I designed transformers, but have no experience with audio.
>>>>>
>>>>
>>>> ** If you did, you might know that a standard, tape wound toriodal core auto-tranny would meet the OP's spec with complete ease.
>>>>
>>
>> Great! Suggest a core manufacturer and part number.
>>
> 
> ** Any of the folk who do custom toriodals would be fine.
> 
>     Your ignorance of the whole topic is appalling.
> 
>     As are your fucking horrible manners.
> 
> 
> 
> .....    Phil
> 

You have a mental problem, Pfill, which makes you think my "fucking 
horrible manners" are worse than yours. Except for you, I do not abuse 
the posters of this group in the manner of your own "fucking horrible 
manners".

On Tue, 10 Sep 2019 09:49:16 -0500, John S <Sophi.2@invalid.org>
wrote:

>On 9/9/2019 11:44 PM, jlarkin@highlandsniptechnology.com wrote:
>> On Mon, 9 Sep 2019 21:08:16 -0700 (PDT), Phil Allison
>> <pallison49@gmail.com> wrote:
>> 
>>> jla...@highlandsniptechnology.com wrote:
>>>
>>> -----------------------------------------
>>>
>>>>
>>>>> Winfield Hill making an utter ASS of himself again wrote:
>>>>> -------------------------------------------------------
>>>>>>
>>>>>> Phil Allison wrote drivel
>>>>>>
>>>>>
>>>>> ** My complaints were rock solid.
>>>>>
>>>>> You made no attempt to reply to any of them.
>>>>>
>>>>> One would have to be forgiven for declaring you to be a pompous ass.
>>>>>
>>>>>
>>>>>>   Give it a rest Phil.
>>>>>
>>>>>
>>>>> ** FFS never post such absurdities about audio again.
>>>>>
>>>>>    Or else the gloves come off.
>>>>>
>>>>>
>>>> Phil, have you designed any interesting audio power amps? Please post
>>>> something.
>>>>
>>>>
>>>
>>>
>>> ** This is not any kind of reply to my post.
>>>
>>> Not able or willing to post a real reply, the totally disingenuous prick goes on a trolling expedition.
>>>
>>> FYI: Since I am not a fish, I will not be biting.
>>>
>>> Larkin just keeps on proving what a piece of low life scum he is.
>>>
>>> His rampant autism is no excuse for being such a total ass.
>>>
>>>
>> 
>> Nothing to show us?
>> 
>
>Of course not. He has probably never designed an amplifier. He is just a 
>repair service.


As noted elsewhere, many people here who work around electronics, but
don't actually understand and can't design electronics, are foul and
angry. Not always, but too often.

I've seen that in Silicon Valley: the techs and pcb layout people
resent and mock the engineers. Well, the male ones do. There are two
distinct cultures.

In sed, the more competent people are at electronic design, the
friendlier and more helpful they tend to be. And the more they show
their work. And they use their real names.

Electronic design is sorta scientific, but personality matters.
Schools should teach that.

On Sun, 8 Sep 2019 14:41:21 -0500, John S <Sophi.2@invalid.org> wrote:

>On 9/8/2019 9:53 AM, jlarkin@highlandsniptechnology.com wrote:
>> On Sun, 8 Sep 2019 04:24:17 -0700 (PDT), Phil Allison
>> <pallison49@gmail.com> wrote:
>> 
>>> John Smug, imitating a troll wrote:
>>> --------------------------------
>>>>
>>>>
>>>>
>>>> If I understand your configuration correctly, you have an
>>>> autotransformer driven in a class B connection at the ends. The
>>>> transformer will need to have the thinnest laminations you can get in
>>>> order to handle the 20kHz.
>>>>
>>>
>>> ** Utter nonsense.
>
>>> It's a wide band audio power tranny, not a SMPS.
>
>Using .029 thick steel will not be good. What lamination thickness do 
>you recommend?
>
>>>> You will need to have enough laminations
>>>> (core) to not saturate at 20Hz.
>>>
>>> ** Right, full power at 20Hz happens all the time in audio ...
>>>
>>>    Strewth.
>
>
>I know, but what is Strewth? Is that a foreign language? Or maybe you 
>are off you medications again.
>
>>>
>>>> I suggest the following specifications for your transformer:
>>>>
>>>> Autotransformer (bifilar winding)
>>>> 20Hz - 20kHz
>>>> Current - 10Arms
>>>> Voltage rating is not a problem. Even the wire enamel can handle it.
>>>> Suggested lamination source: Thomas & Skinner (No connection with them).
>>>>
>>>> I designed transformers, but have no experience with audio.
>>>>
>>>
>>> ** If you did, you might know that a standard, tape wound toriodal core auto-tranny would meet the OP's spec with complete ease.
>>>
>
>Great! Suggest a core manufacturer and part number. Also suggest number 
>of turns and wire size. That would prove you know what you're talking about.
>
>

I was playing with this,

https://www.digikey.com/products/en?keywords=1182L30

a 50/60 Hz power transformer. Leakage inductance is microhenries, and
it's pretty good out to 100 KHz.

On 9/10/2019 10:20 AM, jlarkin@highlandsniptechnology.com wrote:
> On Tue, 10 Sep 2019 09:49:16 -0500, John S <Sophi.2@invalid.org>
> wrote:
> 
>> On 9/9/2019 11:44 PM, jlarkin@highlandsniptechnology.com wrote:
>>> On Mon, 9 Sep 2019 21:08:16 -0700 (PDT), Phil Allison
>>> <pallison49@gmail.com> wrote:
>>>
>>>> jla...@highlandsniptechnology.com wrote:
>>>>
>>>> -----------------------------------------
>>>>
>>>>>
>>>>>> Winfield Hill making an utter ASS of himself again wrote:
>>>>>> -------------------------------------------------------
>>>>>>>
>>>>>>> Phil Allison wrote drivel
>>>>>>>
>>>>>>
>>>>>> ** My complaints were rock solid.
>>>>>>
>>>>>> You made no attempt to reply to any of them.
>>>>>>
>>>>>> One would have to be forgiven for declaring you to be a pompous ass.
>>>>>>
>>>>>>
>>>>>>>    Give it a rest Phil.
>>>>>>
>>>>>>
>>>>>> ** FFS never post such absurdities about audio again.
>>>>>>
>>>>>>     Or else the gloves come off.
>>>>>>
>>>>>>
>>>>> Phil, have you designed any interesting audio power amps? Please post
>>>>> something.
>>>>>
>>>>>
>>>>
>>>>
>>>> ** This is not any kind of reply to my post.
>>>>
>>>> Not able or willing to post a real reply, the totally disingenuous prick goes on a trolling expedition.
>>>>
>>>> FYI: Since I am not a fish, I will not be biting.
>>>>
>>>> Larkin just keeps on proving what a piece of low life scum he is.
>>>>
>>>> His rampant autism is no excuse for being such a total ass.
>>>>
>>>>
>>>
>>> Nothing to show us?
>>>
>>
>> Of course not. He has probably never designed an amplifier. He is just a
>> repair service.
> 
> 
> As noted elsewhere, many people here who work around electronics, but
> don't actually understand and can't design electronics, are foul and
> angry. Not always, but too often.
> 
> I've seen that in Silicon Valley: the techs and pcb layout people
> resent and mock the engineers. Well, the male ones do. There are two
> distinct cultures.
> 
> In sed, the more competent people are at electronic design, the
> friendlier and more helpful they tend to be. And the more they show
> their work. And they use their real names.
> 
> Electronic design is sorta scientific, but personality matters.
> Schools should teach that.


It's a shame. Phil has so much to offer technically, but he has no 
control over himself if someone disagrees with him. Instead of replying 
with helpful technical information, he insults the poster who he thinks 
has less intelligence than himself. He thinks he is the final authority 
in that particular thread.

On 9/10/2019 10:23 AM, jlarkin@highlandsniptechnology.com wrote:
> On Sun, 8 Sep 2019 14:41:21 -0500, John S <Sophi.2@invalid.org> wrote:
> 
>> On 9/8/2019 9:53 AM, jlarkin@highlandsniptechnology.com wrote:
>>> On Sun, 8 Sep 2019 04:24:17 -0700 (PDT), Phil Allison
>>> <pallison49@gmail.com> wrote:
>>>
>>>> John Smug, imitating a troll wrote:
>>>> --------------------------------
>>>>>
>>>>>
>>>>>
>>>>> If I understand your configuration correctly, you have an
>>>>> autotransformer driven in a class B connection at the ends. The
>>>>> transformer will need to have the thinnest laminations you can get in
>>>>> order to handle the 20kHz.
>>>>>
>>>>
>>>> ** Utter nonsense.
>>
>>>> It's a wide band audio power tranny, not a SMPS.
>>
>> Using .029 thick steel will not be good. What lamination thickness do
>> you recommend?
>>
>>>>> You will need to have enough laminations
>>>>> (core) to not saturate at 20Hz.
>>>>
>>>> ** Right, full power at 20Hz happens all the time in audio ...
>>>>
>>>>     Strewth.
>>
>>
>> I know, but what is Strewth? Is that a foreign language? Or maybe you
>> are off you medications again.
>>
>>>>
>>>>> I suggest the following specifications for your transformer:
>>>>>
>>>>> Autotransformer (bifilar winding)
>>>>> 20Hz - 20kHz
>>>>> Current - 10Arms
>>>>> Voltage rating is not a problem. Even the wire enamel can handle it.
>>>>> Suggested lamination source: Thomas & Skinner (No connection with them).
>>>>>
>>>>> I designed transformers, but have no experience with audio.
>>>>>
>>>>
>>>> ** If you did, you might know that a standard, tape wound toriodal core auto-tranny would meet the OP's spec with complete ease.
>>>>
>>
>> Great! Suggest a core manufacturer and part number. Also suggest number
>> of turns and wire size. That would prove you know what you're talking about.
>>
>>
> 
> I was playing with this,
> 
> https://www.digikey.com/products/en?keywords=1182L30
> 
> a 50/60 Hz power transformer. Leakage inductance is microhenries, and
> it's pretty good out to 100 KHz.

I think that is the OP's answer. Good suggestion, John.

I would recommend the 1182S30 part. What do you think?

On Tue, 10 Sep 2019 11:16:00 -0500, John S <Sophi.2@invalid.org>
wrote:

>On 9/10/2019 10:23 AM, jlarkin@highlandsniptechnology.com wrote:
>> On Sun, 8 Sep 2019 14:41:21 -0500, John S <Sophi.2@invalid.org> wrote:
>> 
>>> On 9/8/2019 9:53 AM, jlarkin@highlandsniptechnology.com wrote:
>>>> On Sun, 8 Sep 2019 04:24:17 -0700 (PDT), Phil Allison
>>>> <pallison49@gmail.com> wrote:
>>>>
>>>>> John Smug, imitating a troll wrote:
>>>>> --------------------------------
>>>>>>
>>>>>>
>>>>>>
>>>>>> If I understand your configuration correctly, you have an
>>>>>> autotransformer driven in a class B connection at the ends. The
>>>>>> transformer will need to have the thinnest laminations you can get in
>>>>>> order to handle the 20kHz.
>>>>>>
>>>>>
>>>>> ** Utter nonsense.
>>>
>>>>> It's a wide band audio power tranny, not a SMPS.
>>>
>>> Using .029 thick steel will not be good. What lamination thickness do
>>> you recommend?
>>>
>>>>>> You will need to have enough laminations
>>>>>> (core) to not saturate at 20Hz.
>>>>>
>>>>> ** Right, full power at 20Hz happens all the time in audio ...
>>>>>
>>>>>     Strewth.
>>>
>>>
>>> I know, but what is Strewth? Is that a foreign language? Or maybe you
>>> are off you medications again.
>>>
>>>>>
>>>>>> I suggest the following specifications for your transformer:
>>>>>>
>>>>>> Autotransformer (bifilar winding)
>>>>>> 20Hz - 20kHz
>>>>>> Current - 10Arms
>>>>>> Voltage rating is not a problem. Even the wire enamel can handle it.
>>>>>> Suggested lamination source: Thomas & Skinner (No connection with them).
>>>>>>
>>>>>> I designed transformers, but have no experience with audio.
>>>>>>
>>>>>
>>>>> ** If you did, you might know that a standard, tape wound toriodal core auto-tranny would meet the OP's spec with complete ease.
>>>>>
>>>
>>> Great! Suggest a core manufacturer and part number. Also suggest number
>>> of turns and wire size. That would prove you know what you're talking about.
>>>
>>>
>> 
>> I was playing with this,
>> 
>> https://www.digikey.com/products/en?keywords=1182L30
>> 
>> a 50/60 Hz power transformer. Leakage inductance is microhenries, and
>> it's pretty good out to 100 KHz.
>
>I think that is the OP's answer. Good suggestion, John.
>
>I would recommend the 1182S30 part. What do you think?

It doesn't have the config he wants, one CT winding. He could only use
half of the copper, if that, and it probably wouldn't work for him at
20 Hz. But a toroid roughly that size, or maybe a few notches bigger,
could work.

He could use the Hammond for breadboarding, to get in the ballpark.

On 9/10/2019 11:24 AM, jlarkin@highlandsniptechnology.com wrote:
> On Tue, 10 Sep 2019 11:16:00 -0500, John S <Sophi.2@invalid.org>
> wrote:
> 
>> On 9/10/2019 10:23 AM, jlarkin@highlandsniptechnology.com wrote:
>>> On Sun, 8 Sep 2019 14:41:21 -0500, John S <Sophi.2@invalid.org> wrote:
>>>
>>>> On 9/8/2019 9:53 AM, jlarkin@highlandsniptechnology.com wrote:
>>>>> On Sun, 8 Sep 2019 04:24:17 -0700 (PDT), Phil Allison
>>>>> <pallison49@gmail.com> wrote:
>>>>>
>>>>>> John Smug, imitating a troll wrote:
>>>>>> --------------------------------
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> If I understand your configuration correctly, you have an
>>>>>>> autotransformer driven in a class B connection at the ends. The
>>>>>>> transformer will need to have the thinnest laminations you can get in
>>>>>>> order to handle the 20kHz.
>>>>>>>
>>>>>>
>>>>>> ** Utter nonsense.
>>>>
>>>>>> It's a wide band audio power tranny, not a SMPS.
>>>>
>>>> Using .029 thick steel will not be good. What lamination thickness do
>>>> you recommend?
>>>>
>>>>>>> You will need to have enough laminations
>>>>>>> (core) to not saturate at 20Hz.
>>>>>>
>>>>>> ** Right, full power at 20Hz happens all the time in audio ...
>>>>>>
>>>>>>      Strewth.
>>>>
>>>>
>>>> I know, but what is Strewth? Is that a foreign language? Or maybe you
>>>> are off you medications again.
>>>>
>>>>>>
>>>>>>> I suggest the following specifications for your transformer:
>>>>>>>
>>>>>>> Autotransformer (bifilar winding)
>>>>>>> 20Hz - 20kHz
>>>>>>> Current - 10Arms
>>>>>>> Voltage rating is not a problem. Even the wire enamel can handle it.
>>>>>>> Suggested lamination source: Thomas & Skinner (No connection with them).
>>>>>>>
>>>>>>> I designed transformers, but have no experience with audio.
>>>>>>>
>>>>>>
>>>>>> ** If you did, you might know that a standard, tape wound toriodal core auto-tranny would meet the OP's spec with complete ease.
>>>>>>
>>>>
>>>> Great! Suggest a core manufacturer and part number. Also suggest number
>>>> of turns and wire size. That would prove you know what you're talking about.
>>>>
>>>>
>>>
>>> I was playing with this,
>>>
>>> https://www.digikey.com/products/en?keywords=1182L30
>>>
>>> a 50/60 Hz power transformer. Leakage inductance is microhenries, and
>>> it's pretty good out to 100 KHz.
>>
>> I think that is the OP's answer. Good suggestion, John.
>>
>> I would recommend the 1182S30 part. What do you think?
> 
> It doesn't have the config he wants, one CT winding. He could only use
> half of the copper, if that, and it probably wouldn't work for him at
> 20 Hz. But a toroid roughly that size, or maybe a few notches bigger,
> could work.
> 
> He could use the Hammond for breadboarding, to get in the ballpark.
> 

Yes. The core area needs to be three times larger to handle the 20Hz. So 
choose a transformer for 3 times the voltage at 60 Hz or 180V. The 
windings can be put in parallel to double the current. The primary and 
secondary would be wired parallel with each other and in series after that.

Like this:

Version 4
SHEET 1 880 680
WIRE 64 -32 -64 -32
WIRE 176 -32 64 -32
WIRE 64 0 64 -32
WIRE 176 0 176 -32
WIRE 64 96 64 80
WIRE 176 96 176 80
WIRE 176 96 64 96
WIRE 64 112 64 96
WIRE 176 112 176 96
WIRE 64 208 64 192
WIRE 64 208 -64 208
WIRE 176 208 176 192
WIRE 176 208 64 208
SYMBOL ind2 48 96 M180
WINDOW 0 36 80 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName L1
SYMATTR Type ind
SYMBOL ind2 48 208 M180
WINDOW 0 36 80 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName L2
SYMATTR Type ind
SYMBOL ind2 192 96 R180
WINDOW 0 36 80 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName L3
SYMATTR Type ind
SYMBOL ind2 192 208 R180
WINDOW 0 36 80 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName L4
SYMATTR Type ind