Soliloqueen's k87(k67) and k47 capsules

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updated b-stock k87 count, updated normal count to follow. shipped almost everyone ran out of thermal paper so 3 people are unshipped. will ship monday. happy holidays.

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now that we're doing the metal at my friend's shop and it's so much more expensive, a single sided k87 is less feasible. i'll have to come up with a simple secondary backplate that can still be skinned if i want to do a single sided version. or maybe i'll just make a k103. i'll still look into it tho
 
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updated b-stock k87 count, updated normal count to follow. shipped almost everyone ran out of thermal paper so 3 people are unshipped. will ship monday. happy holidays.

edit:
now that we're doing the metal at my friend's shop and it's so much more expensive, a single sided k87 is less feasible. i'll have to come up with a simple secondary backplate that can still be skinned if i want to do a single sided version. or maybe i'll just make a k103. i'll still look into it tho
Hi, maybe photosensitive 3D printing is a good choice. It has enough precision for the structure, so only one layer of electrode plate is needed, which should reduce costs
 
naval brass is alright. we ended up going with silicon brass 697 instead. the silicon brass was just easier to make into tiny screws. i know it's most likely that it's just copper patina, but some of these spots look too disconcertingly silvery for my taste.

In agreement with Disco Volante, IIRC from metallurgy class in welding school, red silicon brass is extremely resistant to dezincification and is even rated for potable water contact.

Just being curious out loud here: have you looked into using 360 brass? I've done every machining process imaginable on gobs and gobs of it, and there's literally nothing in existence that machines so easily, smoothly and precisely. It's simply a dream to work with, and highly resistant to corrosion and dezincification. I suspect you might've already checked into it, but the 3% lead content perhaps renders it non-compliant with RoHS in what would be considered an electronics application?
 
In agreement with Disco Volante, IIRC from metallurgy class in welding school, red silicon brass is extremely resistant to dezincification and is even rated for potable water contact.

Just being curious out loud here: have you looked into using 360 brass? I've done every machining process imaginable on gobs and gobs of it, and there's literally nothing in existence that machines so easily, smoothly and precisely. It's simply a dream to work with, and highly resistant to corrosion and dezincification. I suspect you might've already checked into it, but the 3% lead content perhaps renders it non-compliant with RoHS in what would be considered an electronics application?
Leaded brass like this is what's traditionally used for backplates so of course we use it I just hadn't thought about using it for screws.

360 is so common and irreplaceable in electronics that the rohs actually has an explicit exemption for 360 brass. Look it up!
 
updated b-stock k87 count, updated normal count to follow.
@soliloqueen

forgive me for bothering you.
A long time ago I asked you if there would be K87 B-stock capsules. You replied that no, the assembly of pod halves is only done with matching capsule halves.
We all understand the special situation that has arisen, we are very sorry, everything must be done to be able to continue and support the business
So the current capsule on the Arienne site, the B-stock - K87 cardioid/omni has the front half conforming to your standard Arienne benchmark set by the vintage K67 capsule? And the rear half has more deviations than you would have liked?
Thank you very much!
 
@soliloqueen

forgive me for bothering you.
A long time ago I asked you if there would be K87 B-stock capsules. You replied that no, the assembly of pod halves is only done with matching pod halves.
We all understand the special situation that has arisen, we are very sorry, everything must be done to be able to continue and support the business
So the current capsule on the Arienne site, the B-stock - K87 cardioid/omni has the front half conforming to your standard Arienne benchmark set by the vintage K67 capsule? And the rear half has more deviations than you would have liked?
Thank you very much!
"no b-stock" is theoretical. in reality, the amount of non matching capsules trends towards zero as the batch size increases. we were only able to make 100 this time, so there were a few even if the sound is correct on both sides.
 
Thank You very much,Ari!!!
also keep in mind that my threshold for b-stock is a difference of 1% in capacitance, about 0.6pf¹, or about 0.15dB. this may be much more than you care about. the reasonable cutoff for an acceptable figure 8 pattern is like 0.20dB.

1. benchtop LCRs are not this accurate, but they are this precise. Provided you don't change the environment, you can get a delta between two sides this precisely. the numbers just won't be reference correct, but that doesn't matter for this use case.
 
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Received my K87s yesterday. Discovered last night that PCBs I ordered from Danny are not the correct ones for the body I have. There was even a note about which boards to get when ordering the mic body but I cannot read (I was promised two things when I got into this business, no math and no reading).

I got the capsules installed today in anticipation of the new boards I ordered. Debating whether or not to get more capsules and transformers and build them into a mic body that fits the tapered boards.

The build quality on these is very excellent. Can't wait to hear them in the circuit.

Thanks!

Paul
 

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updated b-stock k87 count, updated normal count to follow. shipped almost everyone ran out of thermal paper so 3 people are unshipped. will ship monday. happy holidays.

edit:
now that we're doing the metal at my friend's shop and it's so much more expensive, a single sided k87 is less feasible. i'll have to come up with a simple secondary backplate that can still be skinned if i want to do a single sided version. or maybe i'll just make a k103. i'll still look into it tho
Are B-stock k87 capsules available through your site? I would like to try to grab two more of the multi pattern version if possible.

Thanks!

Paul
 

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