OPEN SOURCE DIY Mic Project - ORS 87 - Stripped Down u87

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Thanks all! Yup, first one is real 87. Both recorded at the same time. Just done super quick as a test, not in gig mode. I just hand held the ORS87, so not scientific at all. Definitely more sibilant, but workable. Would like to hear a better capsule in here.
2n3819 Bias set at about 8.4v
Haven't really compared noise vs the LSK-189 yet.
What I hear is the ORS87 has the foundational sound of a real 87, even with what is about $125 in parts, which is crazy when you think about it. Because it shows, at the same time, how simple the 87 is and yet also how much it takes to go from 90 percent there to all the way. And yet, I think there's still plenty of ground to gain here.
My consideration comes down to the question of how good a spare it is: Could I dub one in for the other, if need be? And I think, for example, if a client told me they changed the interest rate on an auto loan and I need to recut a sentence or two, I could cut that new donut on this ORS87 if I had to and get a close enough match to the original that the end listener wouldn’t be able to tell. Could I gig with this mic? I think so.
I’m just surprised this old CAD body sounds this decent. I had written these things off years ago.
I think the big takeaway from this build is that I can now definitively say that I like the Neutrik NTE 10/3 better for the 87 sound than the Ali T-13.


UPDATE: After spending a little more time comparing it to the 87, with a rested voice, I don't think it's as close as I first thought. I blame my exuberance. I think there's still midrange-damping happening with this headbasket, and the capsule is still average at best. But I'm still very enthusiastic about what it does sound like. I'd be willing to take this mic on a trip in case it was needed and not worry if anything happened to it.
 
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Hi there,

Just chippin'in. I have worked on a version of a U87/U87Ai, I made my own PCB's.
I used the Neutrik 10/3 in most of them. They sound really good compared to a genuine Neumann U87Ai. Hard to beat the real Neumann Capsule sound though. So +1 vote for Neutrik.

What baffles me a bit in this open source U87, is the need to add so much capacitance at C3-C4-C5-C6 (C110-1uF/50V on original Neumann). But hey! Tweak along and have fun guys.

PS: sadly I can already see the "Stripped Down U87 PCB's" adds for sale on the net (vultures).😂

M
Check this on the chat best
 
where did you find that (updated) Khron's BOM !?
Could you point me to it or having a BOM file to share...

thanks
0-0
Khron discusses what he'd change from the original BOM here:
https://groupdiy.com/threads/open-source-diy-mic-project-ors-87-stripped-down-u87.86814/post-1144058

And Homero's BOM, which followed this discussion can be derived from his schematic. This is what I used on my two Homero PCB builds.
https://groupdiy.com/threads/open-source-diy-mic-project-ors-87-stripped-down-u87.86814/post-1144815
 

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