Re: U47 clone transformer lamination alloy

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Moby

www.mobytransformers.com BV.8, Bv.11, Bv.12, T14/1
GDIY Supporter
Joined
Jun 3, 2004
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BraFra said:
Hi max,
I've read that you are doing lamition by yourself for this transformer, could describe the alloy mixture used? The same as A51 garantie that u described in the bv-08 post? May i ask if is possible to buy those lamination from you? Thanks and sorry for the little ot.

Fra
I doubt it's the same chemistry since it's obsolete more than 30y. But it's possible to find similar permeability magnetic material and to cut it to shape. Bad thing is that it need to be heat treated after that kind of stress. I don't say that max's lams are bad , just that It's hard to believe that he made exact chemistry / (It's not possible to make it in small quantity, say under 2T because of complex manufacturing process). Correct me if I'm wrong ;)
 
ioaudio said:
Thanks for the kind words evryone!

Brabra,

i'm using the alloy and, more importantly, the "Glühvorschrift" spezified to the VAC Garantie A-50.
The Glühvorschrift describes the final heat treatment after stamping the laminations, setting all the magnetic parameters.
I also do this in-house in rather small batches, and at the moment i need all the material i'm afraid.

Moby,

i think your post contains a lot of assumptions and i'm not sure where you'd get them.
I spend several years researching sources for the alloy, the stamping tools and, as described above, the heat treatment to obtain certain parameters.
But of course, buying a sheet of whatever google finds on the term mumetall and cutting it into pieces wont do.

micaddict,

no new twist, all original Bv.08 transformers have been made on the chambered bobbins.
PICT0170.JPG


-max

Max, remember the mail I asked you about lams chemistry? Well U never answer but I'm sure you remember that I wrote that I have a source for same chemistry lamination. I wanted to give you that contact because I don't have a time to make a business from that ( I do music for a living). If you are suspicious about my knowledge regarding BV8 lams I have to say that I studied that for few years, experimented, measured and finally made serious wavelength Dispersive x-Ray flurescence spectrometry on one of 3 largest metal chemistry institute. What that means? Well, it means that I have measurings of 3 different lams used in the original early U47's (including your first BV8 replica). It includes concentration of 24 different magnetic (and non magnetic elements) and it's represented in 0.0000% accuracy (Search about Rigaku ZSX ). I also measured few more "original" "modern lams replacements" and unfortunately no one matches the samples from 50-70's era. Sorry to say that, but that's true. I decided to write this "short book" not to ruin you business, keep doing it, I wish you many happy customers, but because I like the story about U47 :) I believe your BV8 sounds great and that worths every cent of his price (I will probably order few BV8's from you) An of course if you need some more info you can contact me. You know my mail :)
 
ioaudio said:
Moby,

actually the transformer i sent you in 2008 was made from original laminations Garantie a-52 made by VAC in the 70-ies.
So what you analysed was a product made by Vacuumschmelze Hanau, not my own.
Of course, I analyzed Garantie A-52 (Sourced from Belgium gentleman) winded by you,  and few more original Neumann's (not yours) lams including the early (less nickel) and later (more nickel) BV8's. Of course there is the very first "very low nickel" laminate used in the first U47 but that's another story because it's not UI25 ;) But if you are curious, there is just a slight difference between those and 50's "low nickel" . I don't use "garantie 50,51,52" def's because it's connected just to one manufacturer of the UI25 lamination. Besides VAC U know that Krupp also made these but there is one more manufacturer in that game, actually complete manufacturing went to USSR after the 2. WW. Unfortunately they never stamped UI25's but it's still possible to buy sheets in that thickness and with same chemistry but in large quantities. They also look like VAC's (they are not black anodized) U know that yellowish shine :))) MAX, again, I don't want make any confusion or to share some suspicious minds . I just share my knowledge to the people here in the community. Don't take it personally.
Also, as far I know A52 was never used by Neumann. On the other hand I don't have any problem with it because is soooo, similar to later "H nickel" chemistry. To be precise it contains 2% less Nickel exchanged for Molybdenum because they "improved" that way earlier A51.

EDIT: I made a typo instead of UI25 I typed in hurry UI30 , now corrected
 
ioaudio said:
Moby said:
Of course, I analyzed Garantie A-52 (Sourced from Belgium gentleman) winded by you,  and few more original Neumann's (not yours) lams including the early (less nickel) and later (more nickel) BV8's.

So you analyzed a few different original samples from VAC, but not my current, in-house made laminations made to Garantie A-50 as specified in the Bv.08 blueprint.
Nope. I will be happy to do that :)
 
ioaudio said:
Moby said:
...Sorry to say that, but that's true. I decided to write this "short book" not to ruin you business, keep doing it, I wish you many happy customers...

...MAX, again, I don't want make any confusion or to share some suspicious minds . I just share my knowledge to the people here in the community. Don't take it personally...

What exactly is your agenda?
Agenda? No agenda. I initially chimed in this topic because there was a question about lamination chemistry. Since I'm familiar with BV.8 lamination chemistry and complete history of the same I just told what I know about. If you want me to translate from English to English I can. I'm not suspicious since I never analyzed your in house lams, just commented that producing original alloy is hard to produce in quantity under 2 tons. If you really produced such a large quantity I don't have a problem with that, opposite, I'm really happy because it will be available for approx 16.000 transformers cores ;) That means return of the original sound since modern BV.8 sounds just as bad copies called "upgrade" or "replacement". So what's wrong with that?
 
BraFra said:
Moby said:
ioaudio said:
Moby,

actually the transformer i sent you in 2008 was made from original laminations Garantie a-52 made by VAC in the 70-ies.
So what you analysed was a product made by Vacuumschmelze Hanau, not my own.
Of course, I analyzed Garantie A-52 (Sourced from Belgium gentleman) winded by you,  and few more original Neumann's (not yours) lams including the early (less nickel) and later (more nickel) BV8's. Of course there is the very first "very low nickel" laminate used in the first U47 but that's another story because it's not UI30 ;) But if you are curious, there is just a slight difference between those and 50's "low nickel" . I don't use "garantie 50,51,52" def's because it's connected just to one manufacturer of the UI30 lamination. Besides VAC U know that Krupp also made these but there is one more manufacturer in that game, actually complete manufacturing went to USSR after the 2. WW. Unfortunately they never stamped UI30's but it's still possible to buy sheets in that thickness and with same chemistry but in large quantities. They also look like VAC's (they are not black anodized) U know that yellowish shine :))) MAX, again, I don't want make any confusion or to share some suspicious minds . I just share my knowledge to the people here in the community. Don't take it personally.
Also, as far I know A52 was never used by Neumann. On the other hand I don't have any problem with it because is soooo, similar to later "H nickel" chemistry. To be precise it contains 2% less Nickel exchanged for Molybdenum because they "improved" that way earlier A51.

Very interested in this discussion, may I ask the exact chemistry of A50, A51 and A52? And how this chemical difference impact on the magnetical and electrical result of the core?

Fra
Sorry I can't post the complete chemistry since it's never been published and I really don't know the consequences of making it public. I made all the analyses to learn something or maybe to make old soft magnetics alloy available to the DIY community. But I can share my impressions about some sound differences. There is a big difference between this old and obsolete material because of different magnetic resistivity compared to new and objectively improved soft magnetic alloys. It affects sonic characteristics of transformers. Just take a listen the sound examples at Cinemag site where you can compare old with new alloy directly. They used material containing cobalt NiCo. In the A51 and other original Neumann lams Cobalt is present in less than 0.3%.
 
micaddict said:
Just take a listen the sound examples at Cinemag site where you can compare old with new alloy directly.

Yep. I was some time ago I listened to those samples, but I do remember the very obvious difference. I also remember being amazed that apparently some seemed to think they sounded very similar indeed. Well, some may have been biased, of course.
Not to put down Cinemag BTW. They make great trannies.


Sorry I can't post the complete chemistry since it's never been published and I really don't know the consequences of making it public.

Right now, I can't think of anyone who would not benefit, except maybe yourself. (?)


I made all the analyses to learn something or maybe to make old soft magnetics alloy available to the DIY community.

So exactly in what way will it become available to the DIY community then?
Seriously interested.
Of course Cinemag makes great transformers, there is no doubt. Thing I don't like in their site is info about original bv8 lamination chemistry. That leads me not to trust them, because of misinformation about Nicke\Cobalt alloy used in the original. Well, it's the common example of marketing when other side (in this situation Neumann) has no interests to react.
Regarding my alloy research and giving it freely to the internet users I don't talk about benefit but about possible consequences with present  Bv.8 replica manufacturers. There is one of them doing it  close enough to original and I think he will be really pissed of if I just put that info in the ear . At the end, it's not my point, the point is to make available it again .  As soon as possible I will prepare more info with some useful info  :)
 
ioaudio said:
For anyone interested in the topic of the lamination material, the effects of adding varying amounts of Mo changing the annealing completly etc :Thyssen-krupp published a nice overview about soft magnetic alloys:
http://www.thyssenkrupp-vdm.com/fileadmin/Downloads/Broschueren/pdf/VDM_Report_27_english.pdf
also google for the term "the permalloy problem" if you want to dig deeper.

Over the years Neumann used UI30/25 lamination of Garantie A-50, A-51 and A-52 for the production of their mic transformers.
The colour of the laminations depends on the annealing process, the older Garantie A-50 uses oxidation at a certain temparature point during the heat treatment, setting the dark hue.

Here is a pic of various laminations.
The first two rows are all original VAC UI30/25 lamination, Some of them are made from the same material but heat-treated differently.
Third row left shows two different UI30 (non-25) laminations with four holes. Short-cutting the two legs makes it usable for UI30/25 use.
Third row right shows currently made Magmet 375 UI material already cut to size.
lamination.jpg
Max, I have a feeling that we are mixing apples and oranges here. When you say "magmet 375 UI mateial" I must notice that 375 UI is not alloy type but shape/dimension type. http://www.magmet.com/lamination/375ui.php.  Also, I newer saw  4th lam in seccond  row (4 from left) in the bv8 , or maybe your picture made it too gray... Sorry. It remindes me of UI30/25 lam used in the first models of Rode mic's (btw they sounds good but not in bv8 manner) . Also, when yOu say that cutting ui30 to UI30/25 shape works I must add, yes but how? Untill you heat treat it again iw will work really funky because of mechanicall  stress.
 
BraFra said:
So from what I can understand searching the net, all the three A50, A51 and A52 should have Ni 50% content and Mo content from 3.5% to 4% and Fe to balance. This will tell that the only difference in the alloy mixture is in the Mo and Fe content, but from what Max is saying the Mo content give different response in the heat annealing treatment, and from what I can understand searching the net Vacuumschmelze and Krupp had different approach in this treatment, so how is possible that Neumann used all the two supplier over the time without having to change their transformer?

Fra
Nope. Not even close to true chemistry. Don't try to google about it it will just mislead you . There is a lot false infos on the net regarding this types of  alloys. BTW,  alloys used in the first era of U47 up to 1953. is very different to later (one I tested was from 1958) Let's say that later is more complex , and of course with better permeability.
 
Here are my victims. Sorry for bad lighting, some colors are not so natural because I took the photo in hurry.
First row : (1,2,3) VAC UI30 from 3 available materials.
Second row : Original UI30/25 from Neumann BV.8 (actually, first (4) is not original it's A52)
Third row : Unknown Middle East UI30's
Fourth row : Middle East UI30/25 replicas, with modern chemistry alloys

Feel free to ask for more info.
UI30.jpg

 
I'm afraid that chemical composition is trade secret together with annealing process. It's up to you to listen, compare and finally decide.
 
micaddict said:
Moby said:
I'm afraid that chemical composition is trade secret together with annealing process. It's up to you to listen, compare and finally decide.

I'm still in a mist here. Nothing wrong with secrets, but exactly who "owns" this 60-odd year old knowledge?

possible consequences with present  Bv.8 replica manufacturers. There is one of them doing it  close enough to original and I think he will be really pissed of if I just put that info in the ear .

This person X doing it close enough to original according to you, suggests you know at least as much as he does (more in fact). So why wouldn't you be free to share this? Surely anyone who's capable can do his own analyzing and research. But does this mean that the first one who puts something resembling the old product in the market automatically gets protection and others can no longer talk about the details? Or is there such a thing as patent re-incarnation? Or is it just a gentlemen's agreement about this among "lamination guys"?

Not trying to push you into revealing things you don't want to (and I appreciate the info we did get!). Just trying to make sense out of it. And I basically write this because it seems you're in some sort of a dilemma. You did come over to Max's thread and on the one hand you do want to share or at least help making the old materials available again.

BTW do you sell materials, or do you plan to?
Good questions  :) As far I know "secret" is owned by Neumann, Vac, Krupp initially, but few more small companies know about it too. I' not sure is it copyrighted but in case it is I will be quet  :D The problem with making thiss material is not  just because of knowledge. Main problem is that more modern materials are used in nowdays soft magnetic applications such as shielding etc... It's not a big deal for companies as VAC to make it again but they don't see any profit in pro audio since It's small market. On the other hand  pro audio market is overloaded with different (bad,better or good enaugh) replicas of vintage transformers and I'm not sure is it there a space for new replica products.
The other reason I don't want to share info is because I don't want to ruine somebody buisness or to popularize any company or name. Also, It will be hijacking Max thread and hard work. I just answered on alloy chemical composition question .
Do I have a plan to produce it?  Well, it's possible but we will need a serious number of guys to be interested. We can start a new thread and  put the feeler about it. Also, if Max's lamination is made with exact chemistry there is no need to do that. We still have not that answer, just that it's  proper dimensioned and that coils are wounded based on Neumann's blueprint. I can only judge from the picture (same as you) and it looks a bit "blacky"  (black oxide) what can be the product of different annealing process. Did I miss some answer? Probably yes, but this Ipad's screen is so small for me ;)
 
It's not copyrighted, because if it was copyrighted it will had to have a patent and everybody should be able to find searching over patents, since there is no patent about there isn't also a copyright. Ruining somebody business I don't think since like I've said two of the main builder of transformers replica were wrong about exact percentage of nickel content, so the only effect in the "revelation of this secret" will be that everybody can ask to the builder the chemistry formulation of alloy and only the correct one will gain the right to claim about "historically correct" replicas, I think that in the microphone section of a forum about diy this should be the right thing to do. Anyhow if you want to keep this secret for selling it to someone you can do it, but I think that you should tell it clearly

Fra
Maybe your'e right. I never checked that and to be honest I don't care too much about it  ;) But I wonder where is the interest of lam's manufacturers to tell us about chemistry? If we are DIY guys or musicians we just need good product. Good is something with good sonic and technical characteristics. Am I right? Historically correct is something else but hard to prove in DIY environment. Hard or expensive, whatever ;) One more thing important for this discussion is : Do we really need it? I searched and analyzed all materials (check the picture) because of my curiosity and hunger for knowledge. To sell somebody my knowledge? No way, I will try to help and improve my skills, maybe to find few more people to "reborn" this nice product. It's the  expensive and complex adventure but I'm already in.
Someone suggested a new thread for the discussion of lamination materials...  excellent idea.
Someone is me, that's the easy part of this mission but before that It's really important to find out true about lamination in this thread. Again, I will be happy to find out it's exact as original. That will save me a lot of work and give me few great sounding mic's for relatively small amount of cash :) Ha! I just found my agenda  ;)
 
Gus said:
This kind of thread is one of the reasons I don't post that much anymore.

ioaudio and Moby did work to figure out the lams and treatments.  Did anyone else that asked for information do any work themselves?  Would they even know what to test for? 
I would not give up the information for free.
I really like this forum and I don't have a problem with something I don't know. I ask. If it's free, wow, happy me. If not, then I try to make money and pay ;) But here we don't have a problem with paying. I'm free for giving advice, to give some hard to find part needed for DIY project, run around to make cheep PCB's and such a things. But I have no right to share info about somebody's intellectual property or simple corporative secrets.  If VAC or Krupp don't do that then I have no right to do that. Am I right? But I can try to make things happen .  :) Max, sorry for hijacking your Topic .
 
HellfireStudios said:
If Moby's claims are true, the easy way to resolve the issue is to have Max send Moby some lams to see if the chemistry corresponds with Moby's findings. If it is the same, Max will have a major selling point. If not, then maybe Moby (sorry for the alliteration) could share his knowledge, and a correct re-creation lamination could be produced. Either way it would benefit the DIY community.

-James-
sounds like a plan
 
I believe, but some partial info you gave about chemistry don't match my findings. Also, what's wrong with double checking. I will definitely do that if you want to sell me your new TX. Not because I don't believe you, because I like to do that. Btw, heat treatment is "kunst" but it's repeatable process possible on small samples.
 
ioaudio said:
Ok, i'll ignore user know-it-all and return to my work.
From all your answers here you are the only "know-it-all" person . I know a lot about this subject but never enough. I wish you all the best in your work and when I receive the sample of your new transformer laminate I will post the chemical composition results here so there will be no more secret about it. I hope that many of users will be happy to know that info. OK?
 
Marc Duchesne said:
Moby, I see your point about sharing community, but frankly, there is some limits to invest time into a project and found solutions to problems without a small gratification in the end.  I personally don't have a problem with him not sharing some of this info's. I am happy to pay iaudio money since his selling price is very low for the efforts he is putting into this and I think it is fair. Be careful when you claim he is not sharing because I believe he is sharing a lot already. I agree that you open your own thread about lamination though.
Please read all the questions and answers carefully. I never asked the guy to share, just to prove that alloy is original, but his arguments are poor. Anyway, I'm out of here since just few of users cares about truth. New topic is open here http://www.groupdiy.com/index.php?topic=52099.0  for discussion and maybe for some progress.
 
ioaudio said:
Let me get back to the transformer lamination topic one more time, because i see (on other forums) that there's still some confusion about the alloys.
I collected all the materials i found and gave them away for a RFA showing the most important elements.
I was quite surprised about the variety found in the alloys used over the years:

Laminations.jpg


Sample 12 (not pictured) is from a Gn107 Transformer (predessor of the Bv.08)
Sample 1 to 7 where used in original Bv.08, Bv.11 and Bv12 transformers.
Sample 8 and 9 originate from magmet US and are used in some modern clones.
10 and 11 are medium nickel alloys and where used for some export versions of neumann transformers.

So after all it's quite hard to speak of "the" correct alloy since there are lots of variations.
Variations where also made to simplify/shorten the heat treatment.
Once more this link for those who are interested in the topic: http://www.thyssenkrupp-vdm.com/fileadmin/Downloads/Broschueren/pdf/VDM_Report_27_english.pdf
Interesting. Could you tell me did you measured with or withouth sample preparation? Also, can you name the spectrometer used in your analyses?
 
ioaudio said:
Careful grinding prior the measurement. I do not know which model was used for the analysis.
Sorry, I have to introduce myself befor I ask more. I work profesionally for more than 20 years as chemistry lab technician in the field of materials. Reason I ask is because in my careier I never measured such a clean alloy. Your results looks like predictive results from qualitative analyze. Right?
 

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