Author Topic: New Toroid Output Transformers  (Read 274 times)

Offline steve

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New Toroid Output Transformers
« on: March 20, 2024, 08:41:21 AM »
I see Piltron does not manufacture audio output transformers anymore. I have heard that the weakness
of the OPTs was the small core, thus saturation due to imbalance of output tube plate currents.

I remember seeing the impressive high frequency response of their transformers.

What do you think of the idea of OPTs with much more core material to over come that weakness?
There would probably be some loss of high frequency response, but from 200khz to 150khz or even 100khz,
would that be a problem?

Do you think there would be a market?

cheers

steve
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
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Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
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Offline _Scotty_

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Re: New Toroid Output Transformers
« Reply #1 on: March 20, 2024, 08:52:02 PM »
It wouldn't hurt to try a bifilar wound toroidal transformer. This might be better
sounding than a conventionally wound transformer.
Scotty
« Last Edit: March 21, 2024, 02:05:51 AM by _Scotty_ »

Offline steve

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Re: New Toroid Output Transformers
« Reply #2 on: March 22, 2024, 08:33:34 AM »
It wouldn't hurt to try a bifilar wound toroidal transformer. This might be better
sounding than a conventionally wound transformer.
Scotty

True, they are known for their very low leakage reactance/tight coupling. I would want to
make the core larger than other brands for better bass response, along with continued excellent high
frequency response.

Thanks for your input Scotty. Any more thoughts are more than welcome.

steve
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers

Offline _Scotty_

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Re: New Toroid Output Transformers
« Reply #3 on: March 22, 2024, 11:16:11 AM »
Don't fill the center of the transformers with epoxy or pot them, mount the transformers old school with bolts through the middle and plates top and bottom.
 While we're at it, go all in and make the power transformers secondary windings bifilar wound as well.
A bifilar wound power transformer improves the high frequencies in a solid state
amp and can help save them when they would be otherwise degraded the very large gauge wire
found in the secondary windings of higher VA rated power transformers.
I would think that doing this in a tube amp couldn't hurt and might be worth it.
Hope these ideas are helpful.
Scotty


Offline steve

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Re: New Toroid Output Transformers
« Reply #4 on: March 24, 2024, 08:06:40 PM »
Don't fill the center of the transformers with epoxy or pot them, mount the transformers old school with bolts through the middle and plates top and bottom.
 While we're at it, go all in and make the power transformers secondary windings bifilar wound as well.
A bifilar wound power transformer improves the high frequencies in a solid state
amp and can help save them when they would be otherwise degraded the very large gauge wire
found in the secondary windings of higher VA rated power transformers.
I would think that doing this in a tube amp couldn't hurt and might be worth it.
Hope these ideas are helpful.
Scotty

No, the center would Not be filled. I also plan on a clear covering so one can see the winding itself.

Haven't thought about a power tranny, but easily doable, but interesting thoughts Scotty. Appreciate such.
Should a power transformer have flexible leads or solid wire lead out? Or ask the customer? The solid wire lead
would eliminate solder connections.

cheers

steve

« Last Edit: March 24, 2024, 09:12:55 PM by steve »
Steve Sammet (Owner, Electron Eng, SAS Audio Labs, Ret)
SAS "V" 39pf/m 6N copper ICs,
SAS Test Phono Stage
Acutex 320 STR Mov Iron Cart
SAS 11A Perfect Tube Preamp
SAS 25 W Ref Triode/UL Monoblocks
2 way Floor Standing Test Speakers

Offline _Scotty_

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Re: New Toroid Output Transformers
« Reply #5 on: March 24, 2024, 08:27:22 PM »
Probably a tradeoff on the transformer leads. Solid leads would mean no fooling with the transformer
to attach stranded leads. It may be a ease of production decision. Listening tests would have to done
to determine if the type connection made at that point makes any difference one way or another.
Scotty