Trainwreck transformers specs

[kalinowski]

But no I can't tell you how Ken did, only how you'd go about it if you had the same education.

That's why I asked if the specs are widely available or they're rather secret. Or in other words if they were figured out by whole community or it was a single person effort. To make it clear, I know that it can be a lot of work to achieve a transformer that sounds very close to the original and I respect people that don't want to share that kind of knowledge because it is more that probable that it would be used by others to make money.
I'm not a guy who wants to open his own transformer bussiness, I wanted to use the opportunity that building a trainwreck clone gives me to learn how to wind an output transformer. I will not have a chip on anyones shoulder(yeah, I'm learning english at school ) if I don't get'em. I just asked.

If it's an OT then consider the bandwidth you'd like to push through it and take a look at the transient response- you'd likely not like the transformer to duck when exposed to square. You would see also on OT's that you can put the loading so that it gives maximum power, but that then odd overtones and specifically the 7th would be more dominant,while that's at the peak of what the transfomer can do but that if you choose a lower workingpoint-i.e. impedance, just below the maximum power you'd get a more even overtone response.
You'd have to specify the voltages and the output device to make this though.
This is evident if you know how to design your transformers

I'm gonna repeat what I wrote before. I did read some textbooks about designing transformers and I pretty much know how to do it, I was curious if I can get those specs.

There's easier way. You can buy a toneslut tranny and take it apart using a coil winder which would count number of windings on every layer. You'd have to check how they're interleaved before you'd do it of course.

But that's not my way cause if I bought toneslut OT I'd use it in my amp because I don't plan building more than one. And I'll probably buy it, just need to earn some more money to cover shipping cost.


peace,

Michal

[BJF]

Hi Michal,

I have told what I can tell on that it might be helpful.

No, I do not sell or make transformers.

In my opinion, you do not have to get those specs,you ask for, if you know how to make or design a transformer but you would be able to count backwards from information given and anyway you'd know what to do.

What do you think a US naval radio officer would teach in terms of electronics?

Please disregard, anything I post that does not fit you, I only did try to be helpful in what way I can.


Be well and and believe in your abilities
BJ


Affiliations
BJF Electronics
Sweden
www.bjfe.org
www.mpamp.com

[VacuumVoodoo]

Hi Michal,

Tom page - I guess you won't have any problems with the language

As for specs, Kens or anyone elses. I too do not know what specs Ken submitted to his transformer suppliers.

Most basic specs can be:

P=50W, FPBW: 70-12000kHz, Raa =8k, ZL= 4,8,16 Ohm

If you've done 15% of your homework you will also specify max primary IDC.
Another 15% of homework will tell you to specify what power tubes will be used and their operating conditions i.e B+ in addition to I(bias)

Next 10% of homework will teach you to specify how windings should be interleaved, choose core material, what diameters of winding wire to use, how many turns per section etc. If I understand correctly what you're saying you already know this.

The remaining 60% you'll have to "discover" on your own. Hint: just as you can draw load lines for tubes and graphically analyze distortion characteristics of a particular gain stage or push-pull pair so can you draw load lines for magnetic circuit i.e. a transformer on the set of hysteresis curves for the core you intend to use and analyze distortion characteristics in analogous way.
When you will have done all this and discover how to match tube characteristics to magnetic properties of core material to design a transformer that together with your chosen power stage design will produce required distortions you will be able to give a manufacturer very exact and detailed specifications. 95% of manufacturers will then say you don't know diddly squat about transformer design.

Since you're a student: what you discover yourself you'll know all your life, what others try to teach you is easily forgotten next day.

Also, if you can read russian try this monumental work on transformer design

[martins3325]

I know how to design a output transformer. Question is how Ken did it. Cause OT is gonna have enormous impact on sound I'd like to reproduce Ken's OT if I want to make a clone.

Of course I can buy toneslut transformers but I wanted to take DIY one step futher as it would go together with my study.

m.

Im not an expert by anymeans on this..but if you wanted to copy Kens transformer..seems like all you would have to do is reverse engineer a Stancor a-3801 for an Express --nothing custom about it-..just not made anymore- or a Dynaco A420 for a Rocket...as I believe that is what was used. Not exclusively..as some Expresses had Pacifics..I think Geetar Pickers is a Pacific...as is the one in my clone. So if I am understanding this correctly wouldnt the solution be to buy one of those..and spec it out, if you have those kinda skills and you wanted to start making them?

[Pongo316]

But no I can't tell you how Ken did, only how you'd go about it if you had the same education.

I did read some textbooks about designing transformers

Michal

Michal I would be intrested in finding out re transformers as well , this stuff is intreging almost seems like a lost art to me.

any one know where there is more information in regards to building and designimg transformers ?

[kalinowski]

thanks for all answers guys,

Michal I would be intrested in finding out re transformers as well , this stuff is intreging almost seems like a lost art to me.

unfortunately I don't know any english books about designing transformers. I found all I needed in Cykin's book that was mentioned before.

Hint: just as you can draw load lines for tubes and graphically analyze distortion characteristics of a particular gain stage or push-pull pair so can you draw load lines for magnetic circuit i.e. a transformer on the set of hysteresis curves for the core you intend to use and analyze distortion characteristics in analogous way.
When you will have done all this and discover how to match tube characteristics to magnetic properties of core material to design a transformer that together with your chosen power stage design will produce required distortions you will be able to give a manufacturer very exact and detailed specifications. 95% of manufacturers will then say you don't know diddly squat about transformer design.

thank you for that, I'll try to figure that out some more.

[paulruby]

You could try asking heyboer. They're pretty open about stuff. Just ask them core size, wire size and number of turns. They might not want to tell you the interleave, but you can ask. The worst that can happen is they don't respond...