American octal steel tubes in LDC microphones?

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According to this document, there's better protection for something that has no purpose, than for something that's arguably an improvement on the state of the art.
Sees weird to me...
That's exactly how it should be...if something is an improvement on the state of the art, it should not be withheld from public use for too long...

I do have a bit of beef, but I don't disagree with your points overall! I understand needing to do what you need to do to survive, I just wish people paid more attention to Neumann's newer products I suppose. I have heard...rumblings of discontent from Sennheiser and Neumann engineers alike, a few long-timers leaving, but not so much that I have any ability to say for sure. This is my opinion, as stated. I totally get doing what you gotta do to make sure you don't go under. To some extent, that's the clone capsules for me, before moving on to my original designs, so I'm doing the same thing! Ideally, my goal is to be able to afford a place to live before I start building full mics and doing original capsule designs.
 
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Neumann obviously didn’t invent general headbasket type to begin with, but I will note to concerned parties; the aspect that seems to create protection over the U87/U67 is the “sidebars” being angled, not perfectly parallel…when in combination with the other aspect of the angled basket.

Note that the M49 headbasket *originally designed outside Neumann and licensed to Neumann for manufacture*, and derivatives, are not protected. Also note the Mojave headbasket, various Sony headbaskets, and others, all with sidebars perfectly parallel. So, it is not the angled mesh or straight top bar that creates the problem, in and of themselves.
 
Neumann obviously didn’t invent general headbasket type to begin with, but I will note to concerned parties; the aspect that seems to create protection over the U87/U67 is the “sidebars” being angled, not perfectly parallel…when in combination with the other aspect of the angled basket.

Note that the M49 headbasket *originally designed outside Neumann and licensed to Neumann for manufacture*, and derivatives, are not protected. Also note the Mojave headbasket, various Sony headbaskets, and others, all with sidebars perfectly parallel. So, it is not the angled mesh or straight top bar that creates the problem, in and of themselves.
I think personally that those things are included in the trademark, it's just that pursuing legal action is at their own discretion based on whether they think it harms their business specifically, which is fair! Mojave doesn't make clone mics and neither does Sony, largely, so it's not an issue. We should probably get this thread back on topic tho
 
According to this document, there's better protection for something that has no purpose, than for something that's arguably an improvement on the state of the art.
Sees weird to me...
I'm not sure the definition of trademark's domain is the same all over the world.
I don't know much about microphones but do know a little about IP... In the area of patents there are "utility" patents that offer protection for limited time in exchange for publishing the useful novel technology. Alternately there are "design" patents that protect artful shapes (like the classic coca cola bottle).

Associated with trademark law there is a somewhat subjective design aspect called "trade dress" that encompasses things like color schemes, control layouts, etc. One classic example of trade dress are manufacturers copying the iconic color schemes of some popular hand held VOM (like Fluke's).

The shape of a microphone seems like it would fall under the purview of design patents, BUT if the shape is driven by functionality that may not be protectable, other than by utility patents and only if novel.

JR
 
My understanding is that a patented design can be used by other parties as long as royalties are being paid...?
that's correct, but patent laws are designed so that someone cannot ownership of something useful forever just because they invented it. if protections over improvements to designs were stronger, it can start to become difficult to get the rights to use a previous design as a base for further improvement if you're another inventor, so it would slow down the improvement of the state of the art. if something is inconsequential, it's OK to protect it more strongly. most countries supply patents for improvements, which is the main way this issue is prevented, but there are also time limits on certain kinds of patents, usually 20 years long, to keep someone from maintaining total control over a technology for long. the reasoning for this is...complicated. many improvements come about through manufacturing of an existing design, by inventors that come up with their improvement through manufacturing of that existing design, so it's good for progress to set a time limit. this is a pretty delicate balancing act though. you don't want to screw someone out of getting paid for their work, but it's important to maintain openness in the idea market too. as a result, in many countries, the result is as you observed: designs that improve the state of the art have time limits and may be harder to enforce whereas design changes that are inconsequential can be protected eternally and may be easier to enforce.

in summary: it's easier for mcdonald's to prove you stole their sign than their food, and there are reasons why that makes sense. i don't think it's ideal, but it's been tried-and-tested a lot.
 
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The most legendary tube in microphones is without doubt the German steel tube VF14.

But what about the American octal steel tubes from this era? I'm talking about the wonderful 6C5, 6J5, 1620, and 6J7. Were these also used for this job in the past?
Has anyone tried this before? The specs are not that far off from a EF12/13/14 or even VF14. The American steel tubes mentioned have, as triode, all a gain around 20 and an internal resistance around 10k or less. No idea how these tubes would behave with the extremely high grid resistors, it would depend on a test.
Sure you would have to select for microphonics (as always) but at the current prices for NOS tubes this is much more pleasant than with their German counterparts. Another advantage are the gridcaps, which would isolate the high impedance part very well from the rest.

Does anyone have any experience with this?
Just wondering in regards to the original post and potential alternatives. How many of you have a test setup with something like 47 circuit(or other circuit of interrest), with swappable tube, transformer... where you inject music material through typical pf range cap simulating capsule and listen to "re-amped" material. Do null tests, and stuff... I find it easier to test and listen to upper limits of certain component under certain conditions, THD, phase effects, noise, gain, evenual "mojo" of certain component.
 
I think personally that those things are included in the trademark, it's just that pursuing legal action is at their own discretion based on whether they think it harms their business specifically, which is fair! Mojave doesn't make clone mics and neither does Sony, largely, so it's not an issue. We should probably get this thread back on topic tho
Well, I think you’re probably wrong but let’s not argue about it. The fact that the sidebars aren’t parallel effects the standing waves on that axis, and is potentially viewed as non trivial. I would just encourage anyone to take a deep dive looking at the *many* headbaskets that haven’t had action taken against them, which simply have straight side bars but all of the rest of the angled headbasket traits. Even from the likes of Samson (https://www.amazon.com/Samson-Techn...SAGM1UPRO/dp/B075KL6ZLC/ref=asc_df_B075KL6ZLC)

Also.

The Sony C48 was one of the earliest U87 clones, but it didn’t also have the headbasket. Anway…
 
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Back to the topic. I don't have a single donor body lying around here in which a 6J7/1620 would even come close to fitting. Damn.

I'm currently in a trial and error phase. This situation is slowing me down this weekend. I think I need to find a bigger body or add a extension tube to the SCT700.

I wonder if that's why these tubes are rarely seen in mics? 😂
My Carrier condenser is the only thing I have that would hold an octal, it's 10 lbs weight and 17 inches long.
 
My Carrier condenser is the only thing I have that would hold an octal, it's 10 lbs weight and 17 inches long.
Yes, it's a bit of a challenge. Since I don't want to wait for a longer body from China, I plan to replace the body tube of the SCT700. To do this, I need to extend the rods and find a suitable steel body tube with the right diameter of 57cm. This is available here in Berlin, unfortunately only with a wall thickness of 2.9mm, which would make the micro really heavy.

Target length would be about 30cm, now it is 18cm long.

20230303_204823.jpg20230303_204714.jpg

If someone is interested, you can get one of these steel body tubes in Berlin (and other locations throughout Germany). 60cm for 4,84€.

Screenshot 2023-03-03 at 21-28-08 Warenkorb.png
 
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Just wondering in regards to the original post and potential alternatives. How many of you have a test setup with something like 47 circuit(or other circuit of interrest), with swappable tube, transformer... where you inject music material through typical pf range cap simulating capsule and listen to "re-amped" material. Do null tests, and stuff... I find it easier to test and listen to upper limits of certain component under certain conditions, THD, phase effects, noise, gain, evenual "mojo" of certain component.
I have something like that. A test setup on which I'm currently trying out everything. Capsules, tubes, PSU, grounding concepts and so on. I'm also trying to build a measuring station for it that can deliver reliable technical data. But I'm still at the very beginning here.

I use a dented t.Bone SC450 USB as a test body. The circuit, as already mentioned several times, is a rudimentary SELA T12. Less is not possible...
20230303_211104.jpg
20230226_095137.jpg20230222_223548.jpg
 
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I would still prefer it if your personal differences were not discussed in this thread. That goes for others too, this isn't the The World vs. K.H. thread. That leads nowhere and only distracts from the actual topic. The thread was already closed once and it would be a shame if that happened again. Please respect that, thank you!

I'm sorry, I visit the forum less often and I missed that the thread was already closed. And I think I was really undeservedly provoked.
To be on topic, I can say that about ten years ago I restored two bottle microphones, CMV 3 and 5. While I was waiting for all the necessary parts to arrive, RE084k especially for CMV3, I tried different electronic tubes. From steel tubes EF12,14 etc. to EF37 and subminiature variants. And at the same time I was afraid that the RE084k I bought would not be good, that it would be too noisy etc. However, in the end everything turned out ok, the RE084k is a really good tube and it was a clear winner in that microphone, and if I ever want to make a microphone big in size and sound at the same time, I will try to do it with RE084k. Although EMRR has now interested me in trying VT24 (864). I have a few of them, a microphone with a DHT tube, that would be an interesting project.
 
that's correct, but patent laws are designed so that someone cannot ownership of something useful forever just because they invented it.
My comment was addressed to yours: "it should not be withheld from public use for too long..."
I believe that a patented design can be duplicated as long as royalties are paid; am I wrong?
 
My comment was addressed to yours: "it should not be withheld from public use for too long..."
I believe that a patented design can be duplicated as long as royalties are paid; am I wrong?
I think we're talking about different things. I meant public use in the literal public sense and long as in more than a decade or two. Sorry for the confusion
 
My understanding is that a patented design can be used by other parties as long as royalties are being paid...?
I don't think licensing is literally mandated in Patent law. The technology becomes public domain after X years, or sooner if the patent holder doesn't keep paying maintenance fees to the USPTO. If you depend on lawyers and patent court to negotiate a fair royalty good luck. Most big dog companies accumulate a war chest of patents that they can trade them like chips with other similar companies to avoid IP conflicts.

Patent litigation is generally a very deep pockets game ($Millions).

I only had second hand experience with one patent infringement lawsuit regarding one of my old patents and my former employer did not win.

JR
 
To be on topic, I can say that about ten years ago I restored two bottle microphones, CMV 3 and 5. While I was waiting for all the necessary parts to arrive, RE084k especially for CMV3, I tried different electronic tubes. From steel tubes EF12,14 etc. to EF37 and subminiature variants. And at the same time I was afraid that the RE084k I bought would not be good, that it would be too noisy etc. However, in the end everything turned out ok, the RE084k is a really good tube and it was a clear winner in that microphone, and if I ever want to make a microphone big in size and sound at the same time, I will try to do it with RE084k
This was certainly a very interesting restoration project. The RE084K is also visually a very beautiful tube. I would have loved to hear the two microphones!
Although EMRR has now interested me in trying VT24 (864). I have a few of them, a microphone with a DHT tube, that would be an interesting
If you ever start a project like this, keep us posted 👍
 
Well, I think you’re probably wrong but let’s not argue about it. The fact that the sidebars aren’t parallel effects the standing waves on that axis, and is potentially viewed as non trivial. I would just encourage anyone to take a deep dive looking at the *many* headbaskets that haven’t had action taken against them, which simply have straight side bars but all of the rest of the angled headbasket traits. Even from the likes of Samson (https://www.amazon.com/Samson-Techn...SAGM1UPRO/dp/B075KL6ZLC/ref=asc_df_B075KL6ZLC)

Also.

The Sony C48 was one of the earliest U87 clones, but it didn’t also have the headbasket. Anway…
A simple work-around for the parallel side bars is to place internal damping material (I use Coax-Seal) on the side bars so it is thicker at the top than the bottom (or vice-versa), producing an internal taper that doesn't alter the external appearance.

I also apply the Coax-Seal in a convex shape, which also diffuses standing waves between the bars.

Personally, I find those LDCs where the head basket is considerably wider at the top, to look really goofy.
 
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A simple work-around for the parallel side bars is to place internal damping material (I use Coax-Seal) on the side bars so it is thicker at the top than the bottom (or vice-versa), producing an internal taper that doesn't alter the external appearance.

I also apply the Coax-Seal in a convex shape, which also diffuses standing waves between the bars.

Personally, I find those LDCs where the head basket is considerably wider at the top, to look really goofy.

Nice one.

An option for people who want to have an angled basket that breaks up standing waves similarly, but don’t want an outer appearance similar to Neumann, is to just have a layer or two of the contoured mesh inside of a rounded headbasket.
 

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