Soliloqueen's k87(k67) and k47 capsules

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When the diaphragm is too relaxed in my experimentation, the mids go wonky if anything. The response can also go absolutely fubar if the loss of tension isn't even like if the ring takes a hit of blunt force. I've seen several people online claim that if you have a wrinkle due to something like that you can loosen the center screw to fix it which doesn't make sense to me and every time I've done it the response of the capsule is absolutely ruined.

I think I saw somewhere that he uses heat? Maybe it's not the tension at all, but something to do with thermal degradation of the diaphragm?
I have 2 Beez kneez k7 capsules ( probably 10years now ) , both have had the center screw come loose .
I ever so slightly "sugged" them back up so the wire wouldn't move . I did not notice a difference in sound right away .
Are these capsules way out of spec now ?
Curious
 
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Question--

In an application where only the front diaphragm is connected, is it best to just leave the rear lead "floating," best to remove it (if that's even possible?) or some other strategy?
I run it through the holes down to where the PCB is and put a quick overhand knot (loose) in it to keep the wire out of the way, and put a piece of shrink on the end to make sure it doesn't make contact with anything..
 
I run it through the holes down to where the PCB is and put a quick overhand knot (loose) in it to keep the wire out of the way, and put a piece of shrink on the end to make sure it doesn't make contact with anything..

I believe this is how I handled it with my two flat K47s.

When the historic K47 comes out I’ll be getting one for a FET47 build, and want to handle it absolutely properly
 
What’s the current time estimate of the historic k47? Itching to build around that beast. Thanks for all your great work @soliloqueen

Also, do you recommend the brass ring flat 47 be retrofit with the new rings?
I am not sure about the next k47. Many other projects first.

This issue doesn't occur for decades. I'd be happy to replace anyone super concerned though. Maybe I'll sell the returns as b stock with a disclaimer.
 
Ah, I didn’t realize so many other things were in the queue. For some reason I was mistaken and thought it was next in line

I guess it’ll make more sense for me to explore other options if I hope to have a mic build done within a few months?

Interested to see what you come up with next regardless!
 
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I just ordered two Flat K47's. But now I am having buyer's remorse. Maybe I shooda bought one of these instead:
www.ebay.com/itm/125848099009
How bow dat? ........... Wait I just lied. I would much rather have the Flat 47's. It is not clear to me what the oscilloscope shot in the auction is telling us about the capsule. DANA.
 
i like how the capsule turned out overall. the mids are about right (which was what I wanted to do vs other capsules in this range) but the 6-8k area is a little off in the very near field. anatomical differences, I think. I think it's better than the equally priced competitors but there's room for improvement.
 
Yesterday i finished a pair of Twin (dual output) microphones with the flat K47 capsules. I used boards with a somehow upgraded NT1a circuit, sold by @dima_k85 on ebay, for having a really low noise floor.
Donor bodies are Recording Tools MC900, aka KEL Audio Sparrow, which give the mics a look similar to the Sphere L22, but smaller.
Will post samples after trying them, but it will take some days or weeks!
 

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"Then I fine-tune the capsule, physically yank it out and using a torque screwdriver, adjust the distance from the diaphragm to the backplate and maybe even adjust the two backplates together. There are basically four parts to this sandwich: diaphragm, backplate, backplate, diaphragm. How these are put together determines midrange behavior, and also determines high and low frequency behavior."

Interesting... Thanks for the link!
 
I have been following the backplate-to-backplate capacity discussion earlier in this topic with great interest.
But when I see that in the U87i the two backplates are connected together for AC with a 10000pF capacitor(!), what would be the difference with a couple of picofarads extra?
Maybe I missed something but as far as I see this isn't an issue at all.
 

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I have been following the backplate-to-backplate capacity discussion earlier in this topic with great interest.
But when I see that in the U87i the two backplates are connected together for AC with a 10000pF capacitor(!), what would be the difference with a couple of picofarads extra?
Maybe I missed something but as far as I see this isn't an issue at all.
Reply #4
It's really about the whole input topology.

https://repforums.prosoundweb.com/index.php/topic,36194.msg531542.html#msg531542
 
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Suspect I'll have enough clips to thoroughly bore people soon, but this is one of my pair of U87 clones with the K87 capsule. Just recorded in my front bedroom, hardly a studio environment. Mainly getting some perspective as my plan was to build these then help pay for them by selling my pair of AT4050s. This clip illustrates nicely the things that were annoying me about the Audio Technica mics...

K87 Acoustic Guitar

AT4050 Acoustic Guitar
 
I have 2 Beez kneez k7 capsules ( probably 10years now ) , both have had the center screw come loose .
I ever so slightly "sugged" them back up so the wire wouldn't move . I did not notice a difference in sound right away .
Are these capsules way out of spec now ?
Curious
I'm no expert but I didn't see a response. My understanding is that it won't change a thing. As long as you don't over torque the centre screw. If it was loose, that's definitely a problem.
 

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