American octal steel tubes in LDC microphones?

[terry setter]

How do the other manufacturers like Telefunken USA do it, for example? Do they buy licences or do they just do it? The question is whether you have to clone at all or just be inspired by the original design?

According to a well-known, but no longer living source, people who were interested in reproducing old classics kept a close eye on the trademarks of aging brands that were no longer doing business. When those trademarks lapsed at 50 years, those same people just took those classic designs and re-registered them under their own names. Completely legal. They got Telefunken and RFK, among others. This is hear-say. I was not present in the lawyers' offices when it happened, but the source is pretty solid (and he told me that he grabbed at least one for himself, too).

You probably remember that a while after Telefunken came back to life, they expanded the name to Telefunken USA. Many folks were peeved to find out that the products that were now being sold were not coming from the same old German company that minted the originals. I always saw the addition of the “USA” tag as a nod in the direction of acknowledging that today’s Telefunken is not the company that operated in Germany during the mid 20th century. I'm not talking about the quality/performance of their products here. That's up to you to decide. I'm talking about provenance/pedigree, and the complexity of trademarks, registration, and patenting.

 

[terry setter]

A popular workaround for the reduced low end of the U47N nuvistor substitution is to replace the output transformer with BV11 type.

I hope that folks catch the significance of this...!

 

[C12VR]

According to a well-known, but no longer living source, people who were interested in reproducing old classics kept a close eye on the trademarks of aging brands that were no longer doing business. When those trademarks lapsed at 50 years, those same people just took those classic designs and re-registered them under their own names. Completely legal. They got Telefunken and RFK, among others. This is hear-say. I was not present in the lawyers' offices when it happened, but the source is pretty solid (and he told me that he grabbed at least one for himself, too).

You probably remember that a while after Telefunken came back to life, they expanded the name to Telefunken USA. Many folks were peeved to find out that the products that were now being sold were not coming from the same old German company that minted the originals. I always saw the addition of the “USA” tag as a nod in the direction of acknowledging that today’s Telefunken is not the company that operated in Germany during the mid 20th century. I'm not talking about the quality/performance of their products here. That's up to you to decide. I'm talking about provenance/pedigree, and the complexity of trademarks, registration, and patenting.

Telefunken USA is a frankenstein company, part premier equipment manufacturer, part conniving corporation.
the picture in the listing below clearly shows the infamous alctron/shuayin type 32mm k67 which we know is the cheapest possible capsule in both quality and price. Maybe there's a de-emphasis circuit in there. I doubt they bothered. It really doesn't even make sense. They know as well as we do that the capsule is where the greatest sound change can be effected, yet they wasted all that money on the amplifier.
and YET they claim:
"non-hyped tonality and unparalleled 'quality for price'."
https://www.telefunken-elektroakustik.com/microphones/TF29Even their own FR plot refutes the first claim, and the second falls by consequence.
the uninitiated consumer pays for a badge one-inch square.

 

[terry setter]

RE: the "Betriebsstandanzeiger". Okay. I haven't seen one in real life yet, that was way before my time.

Have you ever seen a "Magic Eye" record level indicator? Similar function.

 

[abbey road d enfer]

Have you ever seen a "Magic Eye" record level indicator? Similar function.

But utterly different technology. Electrostatic electron beam deflection vs. electrodynamic contraption.

 

[abbey road d enfer]

Wow, just looking at that transformer I'm going to speculate that this mic will have very significant low frequency distortion issues. And, sadly, low frequency distortions can add audible harmonic content throughout the entire audible spectrum, not just the upper octave or so, as some other circuit problems do.

How big does a xfmr need to be for a power level of 50uW?
Many mic input xfmrs are of similar or smaller size when you open the case.

 

[rock soderstrom]

It’s because it’s probably not typical foam, it’s rubber if it’s the usual stuff. (I didn’t click through). Orange open cell rubber sponge.

Yes, this seems to be the same material. Learned something again

 

[rock soderstrom]

Wow, just looking at that transformer I'm going to speculate that this mic will have very significant low frequency distortion issues. And, sadly, low frequency distortions can add audible harmonic content throughout the entire audible spectrum, not just the upper octave or so, as some other circuit problems do.

There are very likely better transformers out there, but I can't find any significant problems with the Neutrik model. On the contrary, I was surprised by the good performance.

This is only a test setup, but I would have no problems to work with it seriously.

 

[rock soderstrom]

Have you ever seen a "Magic Eye" record level indicator? Similar function.

Of course I know "Magic Eyes", those were probably the first electronic components that aroused my interest. As a toddler, I often turned the radio on and off at my grandparents' house just to see the magic eye glow. That was truly magical!

Technically, the two things do not have much in common, see Abbey's post.

 

[rock soderstrom]

You probably remember that a while after Telefunken came back to life, they expanded the name to Telefunken USA. Many folks were peeved to find out that the products that were now being sold were not coming from the same old German company that minted the originals. I always saw the addition of the “USA” tag as a nod in the direction of acknowledging that today’s Telefunken is not the company that operated in Germany during the mid 20th century. I'm not talking about the quality/performance of their products here. That's up to you to decide. I'm talking about provenance/pedigree, and the complexity of trademarks, registration, and patenting.

People with my background are naturally not fans of such activities. I can't change that but I don't like it and I'm certainly not the only one.

The name Telefunken USA also has something to do with the fact that there are still residual parts from the Telefunken Group that are economically active under this name. Telefunken was a large corporation, microphones and recording technology were rather small parts of the company.

 

[abbey road d enfer]

I hope that folks catch the significance of this...!

Which is?
Sorry, I don't catch it... I'm not versed in cryptic messages.

 

[Tubetec]

Behringer had a few variations on the non parralel headbasket design along the way ,


Looks a lot like the Beyer MC740 and 840

 

[soliloqueen]

not to mention that, again, 3d trademarks are only for non-functional aspects, so if the non-parallel sides of the headbasket were all that were covered by the TM, it would inarguably fraudulent. like, it's already arguably fraudulent as it is, but if it were the non-parallel sides, and for the reasons argued here, it would have zero qualifying aspects for a trademark.

 

[kingkorg]

Telefunken USA is a frankenstein company, part premier equipment manufacturer, part conniving corporation.
the picture in the listing below clearly shows the infamous alctron/shuayin type 32mm k67 which we know is the cheapest possible capsule in both quality and price. Maybe there's a de-emphasis circuit in there. I doubt they bothered. It really doesn't even make sense. They know as well as we do that the capsule is where the greatest sound change can be effected, yet they wasted all that money on the amplifier.
and YET they claim:
"non-hyped tonality and unparalleled 'quality for price'."
https://www.telefunken-elektroakustik.com/microphones/TF29Even their own FR plot refutes the first claim, and the second falls by consequence.
the uninitiated consumer pays for a badge one-inch square.

Flat circuit, the same goes for all the all the mics in the series, and RFT ones. AK-47 uses the same 32mm k67 capsule regardless of the name. So many embarrassing reviews by famous engineers on the web praising it for it's classic 47 vibe

According to a well-known, but no longer living source, people who were interested in reproducing old classics kept a close eye on the trademarks of aging brands that were no longer doing business. When those trademarks lapsed at 50 years, those same people just took those classic designs and re-registered them under their own names. Completely legal. They got Telefunken and RFK, among others. This is hear-say. I was not present in the lawyers' offices when it happened, but the source is pretty solid (and he told me that he grabbed at least one for himself, too).

You probably remember that a while after Telefunken came back to life, they expanded the name to Telefunken USA. Many folks were peeved to find out that the products that were now being sold were not coming from the same old German company that minted the originals. I always saw the addition of the “USA” tag as a nod in the direction of acknowledging that today’s Telefunken is not the company that operated in Germany during the mid 20th century. I'm not talking about the quality/performance of their products here. That's up to you to decide. I'm talking about provenance/pedigree, and the complexity of trademarks, registration, and patenting.

Behringer does this A LOT!

 

[Recording Engineer]

Behringer had a few variations on the non parralel headbasket design along the way ,
View attachment 105931
View attachment 105932
Looks a lot like the Beyer MC740 and 840

Also BPM Microphones (made by 797 Audio).

 

[moamps]

Have you ever seen a "Magic Eye" record level indicator? Similar function.

Yes, there are great similarities in the appearance of magic eye vacuum tubes and that indicator. Of course, the working principle is different. When I repaired the aforementioned CMV3 and 5, both indicators were defective, mechanically. These are actually small amperemeters with movable iron. For several months, I followed the German ebay and auctions where electronic "schrott" was sold, and then I bought a box of 3 kg of unnecessary things because there were two or three such indicators inside. I finally managed to put together one that worked. Otherwise, the white surface on the indicator was fluorescent, so when you turned off the light in the studio, and if the microphone was facing you, you would see that you forgot to turn it off. I had a lot of pictures of that microphone, but I lost them all in one horrible WD hard drive failure.

 

[moamps]

Also impressive is the fact that, in the Udo Heusinger document, the foam around the tube is intact after so many years.

The problem with that sponge is that it shrinks over time, and since the electronic tube, its socket and the small PCB are by no means firmly attached to the housing, after a while they start to wobble inside the microphone.

 

[abbey road d enfer]

The problem with that sponge is that it shrinks over time, and since the electronic tube, its socket and the small PCB are by no means firmly attached to the housing, after a while they start to wobble inside the microphone.

Well, I don't know, Udo H. seems to find them in good shape... Maybe it's been replaced at some time. EDIT: for some reason I don't have access to the smiley menu, to express puzzlement.

 

[rock soderstrom]

I had a lot of pictures of that microphone, but I lost them all in one horrible WD hard drive failure.

Autsch, such a shame!

 

[GeorgeToledo]

Behringer had a few variations on the non parralel headbasket design along the way ,
View attachment 105931
View attachment 105932
Looks a lot like the Beyer MC740 and 840

The top picture is likely a headbasket derived from the Beyerdynamic MC740 (edit: I now see that is written below the pics) … which itself may have been derived from the original capsule mount style that U47 had; a very similar shape which enveloped the capsule.