U67/87 Hybrid

[gary o]

hi I have made a point to point version of U67 circuit ( also U87).I have a Max BV12 transformer a great friend gave me but I think the tertary winding is dead.The mic works great without de emph with a flat capsule.I was wondering if I could add the U87 de emphsis circuit of U87 to the U67 ( as my tertary winding is dead) I have very roughly photoshopped a schematic ,Im not sure I would need all the componets of the U87 circuit I have shown.What do you clever people think... Im hear to learn and solder.

Many thanks for reading Gary O.

 

[RuudNL]

The only thing you really need is a de-emphasis to correct the high frequency response of the capsule.
The U87 also includes a fixed low-cut filter, to reduce rumble.
But a side effect is that this also has an influence on the audible lower frequencies.
Here is how I did it: "U67"-ish microphone
Compared to this design, an original Neumann U67 sounds 'thin'.