797 Capsule clone reskining improvement?

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gearhunter

Well-known member
Joined
Sep 7, 2016
Messages
50
Location
Barcelona, Spain
Hi all,

At the moment I have a 34mm K67 797 Audio Capsule in a D-87 build but has suffered humidity from the last owner and needs a reskin.

Would be worth sending the capsule to Mr. Thiersch for reskining? Or reskin only isn’t sufficient to make an improvement and get the response a bit closer to the original Neumann?

Would the result differ much from the usual mid-priced capsule offerings from the market?

Thank you!
 
the difference in treble response is from the lack of spacing groove on the faces I think. changes the air volume behind the diaphragm a bit. reskinning won't improve anything, but it's a pretty nice capsule overall.
 
Hi all,

At the moment I have a 34mm K67 797 Audio Capsule in a D-87 build but has suffered humidity from the last owner and needs a reskin.

Would be worth sending the capsule to Mr. Thiersch for reskining? Or reskin only isn’t sufficient to make an improvement and get the response a bit closer to the original Neumann?

Would the result differ much from the usual mid-priced capsule offerings from the market?

Thank you!
Last time i checked Thiersch wouldn't fix 3rd party capsules, only originals. Reskin wouldn't get you anywhere anyways.

The difference is in backplates as mentioned above. Some knowledgeable people consider those 737s to be improvement to the Neumann design.

More of the high end is a good thing, as you get to use higher value feedback cap and get rid of more of the high end ,which results in less noise in u87 and u 67 designs.

The shape of the response curve and off axis response is what counts, and these capsules have that nailed. There is simply more low and high end. That is easily compensated with EQ and the end result is exactly the same as using darker capsule.

I've had no issues making these sound exactly as u87 in the past. Managed to fool a proffesional mastering engineer who couldn't distinguish between his own vintage u87 and 797 diy project.

Additionaly, those capsules can be disassembled and cleaned as the diaphragm is glued to the ring. So humidity shouldn't be an issue, if the diaphragms aren't damaged phisicaly.
 
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Thank you all for the responses! I'll be getting another 797 K67 separately to replace the one I have and use 400-680pF feedback cap as KingKorg sugestes. On the other hand, what can I do to compensate the low end and aproximate it more to the original?
 
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Make sure you order CY002 model from 797 audio. It is the one with Philips screws.

It would be helpful to post the schematic you are using. It's just another cap you need to adjust.
 
Sorry for the confusion. I decided to leave the CY002 for another build and order a Takstar CTS-2 and a CTS-4 for now. Being 1dB less bright, is 400pf feedback cap the best option?

I contacted them and they tell me that the lead content of copper parts is higher than that of 1000ppm for the samples and if is it acceptable for me. If not they will have to make arrangement. Would that be sufficient enough for a quality sample?
For the PCB I used Poctop's D-87 Tapered version. Does this can be used as the schematic to find the other capacitor value?

Thank you !!

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Thank you Khron and sorry for the newbie question.

If I understand well the max amount of lead permitted is 0,1% and the content of the capsule is higher than 1000ppm.
1000ppm = 1000 parts per 1000000 = 1 part every 1000 which equals to a content higher than the 0,1% limit.

I think that I have to ask for lower than 1000ppm samples if I want to ship to EU without problems.
 
That's only a concern if you're aiming to SELL products using such components, in mass quantities. Otherwise us pedestrians wouldn't be allowed to (even) buy lead-containing solder...

(Not that that day won't come too, especially if the brainless suits get their way...)

It's worth keeping in mind that companies like 797 etc deal mostly with B2B (business-to-business) sales, and as such, with bulk orders possibly meant to be assembled into finished products, in significant quantities. There, RoHS compliance DOES matter.
 
Ok so it seems I had a misconception and in this case as I have no intention to resell the capsules the RoHS complicance is not a concern and I can buy the capsules
 
Thank you Khron and sorry for the newbie question.

If I understand well the max amount of lead permitted is 0,1% and the content of the capsule is higher than 1000ppm.
1000ppm = 1000 parts per 1000000 = 1 part every 1000 which equals to a content higher than the 0,1% limit.

I think that I have to ask for lower than 1000ppm samples if I want to ship to EU without problems.

I bought 4 capsules directly from 797 Audio some months ago,
I just bought standard CY002 and didn't have any problem with customs or with EU Lead content regulation, it was an easy transaction paid for it and receive it at home.

So I guess as you are not importing an huge quantity of capsules to re-sell or release as a product on the market they will not check the lead content.
 
The issue would only be if you were planning to sell a (mass-produced) product that included such components. Customs don't care, as long as the paperwork is in order.

Safety / sales regulating agencies, on the other hand... But even then, only your distributors / retailers might need you to provide certification of compliance with regulations etc. But this is getting a bit derailed now :LOL:
 
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