Making a LDC Capsule - Videos

[dima_k85]

hahahahahahaha

You sound like some guy in a bar trying to pick a fight. I don't care if you don't believe me.

Everything is clear, there will be no proofs.
Statement that "The bond I acheive is certainly better than AKG's" is baseless nonsense.

 

[Whoops]

This dima_K85 account is really suspicious Tim.
It's supposedly registered since 2019, but never contributes anything or posts anything useful in this forum.
It only posted 23 times in 2 years and a half, but still decided to be a Troll in this thread and post 4 posts just to try to insult and irritate you.
And it has the account setup so that it limits who may view his full profile.

I think this is a double trolling account from someone that for some reason want to pick on you.

Just press it's nickname and hit "Ignore" and no more trolling will happen

This thread was being quite interesting with everyone's input and sharing, let's not allow Trolls to disturb that

 

[Tim Campbell]

 

[kingkorg]

Tim please don't fall for this. Either way it's not that relevant, Akg is not producing ck12s any more, and mylar doesn't just start flaking all of a sudden either way. We are blessed for recent contributions from you knowing how busy you are and i hope it will continue.

For all the people wondering, Dima has done nothing else but trolling, never provided any useful content, and is desperate to sell couple of his Rode NT1 rip off boards. Best thing one could actually do is report his account on ebay both to Røde, and ebay for intellectual property infringement. I have no idea why his account is still active here either.

For the sake of this thread JUST IGNORE WHATEVER HE POSTS.

 

[Tim Campbell]

So on with talking about capsules.

 

[OPR]

Great thread! The most interesting thing since Omicron
I'd have to agree with Tim on this. The old AKG and Neumann Sputtering comes off very easily which makes cleaning with liquid extremely high risk!
My diaphragms also have much better adhesion than old Neumann and AKG and they are also very consistent in regards gold thickness.
Good equipment and some know how helps.

 

[GeorgeToledo]

Tim, reading your comment now…is it a matter of sputtering benefitting from the priming with another metal vs the evaporation method not really needing it? Feel free to not say and just smile if it divulges anything that makes you uncomfortable.

 

[Tim Campbell]

For microphones you don't need a substrate. The temperature of gold in a gaseous state is enough to bind it to plastic. This isn't a chrome bumper

 

[OPR]

Tim, reading your comment now…is it a matter of sputtering benefitting from the priming with another metal vs the evaporation method not really needing it? Feel free to not say and just smile if it divulges anything that makes you uncomfortable.

Yes, conventionally you would use an ultra thin layer of a metal that adheres to both mylar and gold more easily than add gold. Not that this is the only way as Tim has pointed out. It may depend on the method and deposition machinery used.

 

[Tim Campbell]

As I mentioned none of my AKG nos material used any substrate and the same film is still in use 60-70 years later. Yes some of it flakes off sometimes but mostly when it is abused.

I went through a lot of emperical testing to make sure I was acheiving a superior bond without a substrate. Gold is heavy enough without adding more weight or stiffness to the membrane by precoating it first.

I use the same deposit amount of all the AKG and Neumann mylar I have measured but honestly you could use an even thinner layer. As long as the membrane is conductive the capsule will work. Some electrostatic speakers have used soap as a conductor.

I have read posts by members here worrying about the thickness of deposits on their capsules. Really this is usually a result of where the piece of mylar was located in the chamber when the sequence was run and shouldn't cause a lot of concern.

 

[OPR]

I went through a lot of emperical testing to make sure I was acheiving a superior bond without a substrate. Gold is heavy enough without adding more weight or stiffness to the membrane by precoating it first.

To clarify the metal used as an adhesion layer is almost invisible. it's weight is less than gold and not enough to affect the stiffness or weight of the diaphragm in any significant or audible way it's sole purpose is to attain superior adhesion which improves long term stability. Obiviously I agree that significantly heavier deposits of gold or a of given adhesion layer would affect the way a capsule sounds because of the additional weight and stiffness it would cause.

 

[OPR]

Not a video, but i wanted to re-share these images of Blue's marvelous approach to modding and tuning k67 capsules. My guess is they use existing k67's and add this tuning disc as a rear backplate to tune the response and polar pattern. So dear people with machining skills here's a simple way to do a killer mod for readily available capsules.

I've experimented with this type of thing also, although it functions, in the end was much better to make an accurate dummy back-plate which will maintain the intended sound of the original design.

 

[Tim Campbell]

If you really want to design a single membrane capsule you should study Schoeps. All of their designs including multipattern are single membrane. They go to great lengths to duplicate the exact same accoustical labrynth for both sides of the membrane. This is the only way to assure that you don't end up with uncontrolled spikes in the freq response of cardioid or fig 8

 

[GeorgeToledo]

In response to #168 and 169 (quoting is fiddly on mobile device)…

I recall learning somehow that Neumann primes their capsules with a nickel based mix before gold, which is why I bring up the issue. Someone there let it slip in discussion, iirc. Take it with a grain of salt I suppose, I didn’t ask any follow up.

 

[Tim Campbell]

In response to #168 and 169 (quoting is fiddly on mobile device)…

I recall learning somehow that Neumann primes their capsules with a nickel based mix before gold, which is why I bring up the issue. Someone there let it slip in discussion, iirc. Take it with a grain of salt I suppose, I didn’t ask any follow up.

As you see from the responses George it isn't that important. And if Neumann did this when did they do it? The M7 PVC era? I don't think so.
There has been so much misunderstanding about this concerning Neumann because many vintage gefell M7's discolor over time but having talked to the engineers at Gefell they told me that this is caused because before the wall came down they tried to save money by using gold alloys to coat their membranes and what we see is the oxidation of these other metals.

If there is proof that Neumann used a substrate I have never found it but I know the engineers there well so perhaps I'll just ask them. Working on vintage Neumann's I haven't noticed a substrate and their gold doesn't have a particularily strong bond, plus nickel is much stiffer than gold. If you have info George please share it.

 

[OPR]

If there is proof that Neumann used a substrate I have never found it but I know the engineers there well so perhaps I'll just ask them. Working on vintage Neumann's I haven't noticed a substrate and their gold doesn't have a particularily strong bond, plus nickel is much stiffer than gold. If you have info George please share it.

Is there proof to the contrary ie. that no adhesion layer was used? I'm not doubting you Tim as I know that you do good work but absence of evidence is not evidence of absence and I certainly have no evidence on this either.

As I said in an earlier post the adhesion layer(done correctly) is very thin and not really visible and absolutely not enough to increase the stiffness or weight of the Mylar, it's literally a dusting with nano particles.

I recall Dale Ulan using an adhesion layer with his wonderful M7 capsules, there may be a thread around here where he discussed this.
some info here.
http://www.10000cows.com/deposition_system.htm
The nano fabrication facilities that I' ve spoken to over the years have all recommended an adhesion layer for PET/Mylar as gold doesn't bond to it very well on it's own, None of this is to say you are wrong in fact the poor adhesion of old Neumann and AKG capsules could possibly even support your hypothesis.

​

 

[Tim Campbell]

I am currently waiting for an answer from Neumann just to be sure. That's why I asked George does he have something actually more than hearsay. You yourself agreed earlier, old Neumann gold is not robust.
As for vintage AKG I can say positively there is no substrate. Before buying the stock that I have now I discussed all the details about their process and they emphatically stated that they used no substrate.

In modern processes yes these layers can be precisely controlled as I do now for my K67 type membranes but 60 years ago the equipment was a bit more rudimentary as seen from old Neumann photos

 

[OPR]

Thanks for you late night answer Tim!
Either way It's not something that affects the sound, using or not using an adhesion layer is likely an economic or production efficiency choice rather than a sonic one.( less steps involved= les time and cost)

It's more important that diaphragm is made of the same material and that the target weight, conductivity and the tuning frequency is met.

I've compared my capsule to quite a few original Ck12 as well as having reskinned quite a few, in the end sound is consistent with the original.

Beyond that we would be falling in some serious cork sniffing territory

 

[Tim Campbell]

Well this was really just to answer George as to if Neumann did use anything as a substrate, not that one is better than the other as I mentioned it seems to make no differece.
I am sure many modern capsules do this.
I'm not even sure that many chinese capsules even use gold.

 

[OPR]

Working on vintage Neumann's I haven't noticed a substrate and their gold doesn't have a particularily strong bond, plus nickel is much stiffer than gold.

No worries Tim,
I just thought I'd clarify in reference to your above statement about Nickel being stiffer than Gold which to me implies some potential negative affect on the way a diaphragm works.
The difference is negligible given the tiny amount used...And given the gold coating tolerances of both Neuman and AKG diaphragms as well as the fact gold is heavier than nickel, would likely have a larger impact on a capsules sound than the tiny amount of nickel used for superior adhesion.
For example some Ck12 coatings are translucent and some are significantly more opaque.