U67 pcb schematics

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tomas.borgstrom

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That might be copyright infringement if the microphone PCBs are a direct copy.
I'll definately be careful. I designed these for myself and just noticed on the forum that other users were requesting U67 PCBs. Both TAB Funkenwerk and Max Kircher have already done the same thing and I haven't heard about any legal actions.

The capsules and the transformers are copied all the time so I can't see why the PCB would be different.
 
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ubxf

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I think as long as it's not a photocopy, One can't claim artwork copyright infringement. You can redraw the same connections but customize it slightly so if you put yours on top of the original they are not the same
 

tomas.borgstrom

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Well, is there any technical (as in,  not fairy-tale) reason only a 100000% identical pcb would be "ok"?
No, besides that the high impedance part of the circuit should be close to the capsule I don't think it matters. Aiming to make the conversion as accurate as possible, electronics and appearance, was a fun challenge.

I remember an interview with Dave Hill where he said that he put a lot of work regarding to the placement of the components on the PCB when he designed Crane Song Flamingo (If I remember correct).
 

Delta Sigma

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I'm very ignorant of copyright law. The way I see it, though; if building the circuit from the schematic is okay, building these boards should be as well. In adapting the circuit to fit a BV.12 and vacuum tube to fit inside a TLM67 or U87, there aren't many ways to do it. Even if you started from scratch, the boards would end up looking similar enough that someone with an interest to claim so, would claim it's a copy. You'd have to try pretty hard to make them look different. There isn't very much room in a TLM67 body.

Not saying it's worth the risk though. Most large companies like, Sennheiser, probably have a bigger legal budget than a design budget!
 

Whoops

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Well, is there any technical (as in,  not fairy-tale) reason only a 100000% identical pcb would be "ok"?

Well the original Neumann layout for the PCB's is much better than poctop pcb option.
The Poctop pcb design is not really nice at all,
I would much preffer to build an U67 project with a pcb similar to the original layout
 

doqmemory

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Well the original Neumann layout for the PCB's is much better than poctop pcb option.
The Poctop pcb design is not really nice at all,
I would much preffer to build an U67 project with a pcb similar to the original layout
Original Neumann design includes the custom body and head. Good luck doing anything besides TLM67/U87ai replacement modules.
If you want to build it in an SYT-5 body, then Dan's PCBs work great. The original layout is not appropriate for the generic bodies available to the DIY community.
 

mad.ax

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The Hi-Z path is located in the headbasket socket and the round PCB under it. But re-designing/re-arranging the components bellow that would allow to replace C9 with a nice film cap, or a PIO... Anything but the original lytic!

Axel
 
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