m70 repair
- Thread starter Gus
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Marik
Well-known member
Hey Gus,
Did you try Gunter Wagner? AFAIK, he is in touch with old Neumann emploees, so he might know something.
I suspect though it might probably be cheaper just to get a new one...
Did you try Gunter Wagner? AFAIK, he is in touch with old Neumann emploees, so he might know something.
I suspect though it might probably be cheaper just to get a new one...
I am taking it apart and taking pictures.
From what I can find the Ni skin is made by galvanicly deposting Ni on Copper and then etching the copper away. Sounds like it makes a mess to make a skin. I think I read it's .8 microns? I have not figured out how the Ni is attached.
From what I can find the Ni skin is made by galvanicly deposting Ni on Copper and then etching the copper away. Sounds like it makes a mess to make a skin. I think I read it's .8 microns? I have not figured out how the Ni is attached.
asm
Well-known member
please post the pics!
i thought gefell was able to repair all their old capsules (even pvc m7's)???
wonder if all nickel is done that way. i could have sworn dale1176 put Ni on a couple of his.
gus, i just got a KK89 capsule which looks interesting. its fully working so unfortuntely no torn apart pics. if you want me to snag some measurements on it let me know.
taylor
i thought gefell was able to repair all their old capsules (even pvc m7's)???
wonder if all nickel is done that way. i could have sworn dale1176 put Ni on a couple of his.
gus, i just got a KK89 capsule which looks interesting. its fully working so unfortuntely no torn apart pics. if you want me to snag some measurements on it let me know.
taylor
AFAIK Gefell still make nickel capsules, so they might be able to repair it.
Stephen Paul was known to repair nickel capsules such as KM54 ones. But, as you know, Stephen Paul passed some time ago, and I don't know if SPA still does that kind of work. But you can always ask. On the other hand, Marik is probably right: a new one might be cheaper.
Stephen Paul was known to repair nickel capsules such as KM54 ones. But, as you know, Stephen Paul passed some time ago, and I don't know if SPA still does that kind of work. But you can always ask. On the other hand, Marik is probably right: a new one might be cheaper.
dale116dot7
Well-known member
The nickel diaphragm is exactly that - nickel. It is made that way using an electroplating process, not on a Mylar sheet. Somewhere on this forum was another thread on how that is actually done.
It is true I have put nickel onto mylar, but that's because nickel and gold are very close in characteristics for evaporation. I used nickel first to get the process right.
Actually, most mic types that used to use nickel diaphragms (generally, small-diaphragm condensors) now use Mylar, with the exception of measurement mics. Those run very high tensions on the diaphragms, and Nickel will hold together where other materials don't. One other mic that was interesting was the Altec M11 'Coke Bottle' that used a quartz diaphragm with a gold coating.
As far as I know, Gefell simply makes a new M7 capsule, rather than trying to clean and re-use the old one. I put on a pair of Mylar diaphragms on an M7 - and most re-skin places do that, as far as I know. Cleaning the adhesive off is no easy task, and you have to be careful so as not to put a scratch on the surfaces.
It is true I have put nickel onto mylar, but that's because nickel and gold are very close in characteristics for evaporation. I used nickel first to get the process right.
Actually, most mic types that used to use nickel diaphragms (generally, small-diaphragm condensors) now use Mylar, with the exception of measurement mics. Those run very high tensions on the diaphragms, and Nickel will hold together where other materials don't. One other mic that was interesting was the Altec M11 'Coke Bottle' that used a quartz diaphragm with a gold coating.
As far as I know, Gefell simply makes a new M7 capsule, rather than trying to clean and re-use the old one. I put on a pair of Mylar diaphragms on an M7 - and most re-skin places do that, as far as I know. Cleaning the adhesive off is no easy task, and you have to be careful so as not to put a scratch on the surfaces.
Martin B. Kantola
Well-known member
- Joined
- Jun 24, 2005
- Messages
- 209
My suggestion is that you ask Gefell to do it for you. They have always been very kind and helpful, and will do capsule repairs as I understand it.
Martin
Martin
jensenmann
Well-known member
I talked to them some weeks ago and they definitely do the repair work for all of their products including old M7 capsules. Btw they still own and use the original machine for M7 production!
:sam:
Jens
:sam:
Jens
But this is not a M7 capsule, is it?
I've only seen M7's with pvc (old) or mylar (new) membranes anyway..
Do they make a M7 with pure-ni membrane? At that size I wouldn't expect it to be stable..
Jakob E.
I've only seen M7's with pvc (old) or mylar (new) membranes anyway..
Do they make a M7 with pure-ni membrane? At that size I wouldn't expect it to be stable..
Jakob E.
Martin B. Kantola
Well-known member
- Joined
- Jun 24, 2005
- Messages
- 209
Kiitos Jaakko! :grin:
Marik
Well-known member
[quote author="gyraf"]But this is not a M7 capsule, is it?
.[/quote]
No, it is M70.
.[/quote]
No, it is M70.
jensenmann
Well-known member
The M70 Capsule is a SDC and is made for the MV690/91/92 amplifiers.
:sam:
Jens
:sam:
Jens
dale116dot7
Well-known member
The M7 cannot be made with a nickel diaphragm unless the backplate is re-designed with an insulator like Tim Cambell's K67-like capsules. The purpose of the nickel was to withstand the tensions required on a SDC capsule, where PVC could not be tightened that much - note that Neumann changed to thin mylar on SDC's after the KM5x family.
SDC capsules are also usually somewhat difficult to re-skin unless the capsule is meant for it.
I didn't clue in to who originated the message till now...
If the skin is clamped (like in the KM54) you might be able to put a 2 micron Mylar skin there, but the mic will sound different. A 2 or 3 micron Mylar skin should be able to be tuned up properly to where a 0.8 to 1 micron nickel skin went.
SDC capsules are also usually somewhat difficult to re-skin unless the capsule is meant for it.
I didn't clue in to who originated the message till now...
If the skin is clamped (like in the KM54) you might be able to put a 2 micron Mylar skin there, but the mic will sound different. A 2 or 3 micron Mylar skin should be able to be tuned up properly to where a 0.8 to 1 micron nickel skin went.
Ian Gillan
Member
I know he makes those nickel diaphragms:
www.thiersch-mic.de
www.thiersch-mic.de
Ask the People at Microtech Gefell. They definitely do these kind of repairs and have the knowhow to do it proper (they are manufacturing the M70 capsule several decades now).
And they are very kind, and have quite reasonable prices, they did several conversions and checks for me.
Florian
p.s.: on the M7 capsule check Klaus Heynes forum http://recforums.prosoundweb.com/index.php/t/5978/0 he's trying to sort it out.
And they are very kind, and have quite reasonable prices, they did several conversions and checks for me.
Florian
p.s.: on the M7 capsule check Klaus Heynes forum http://recforums.prosoundweb.com/index.php/t/5978/0 he's trying to sort it out.
jensenmann
Well-known member
Gus, if those C-tech guys don´t want to support their customers I could arrange the repair at MG or Thiersch here in germany for you. Just drop me a pm.
:sam:
Jens
:sam:
Jens
jensenmann
Well-known member
But 345USD is damned cheap. You don´t get them in Europe for that price :evil:
