TLM67 modification to dual output

[emrr]

What to do with a spare TLM67 electronics set?  Make a dual output microphone, so you can choose the pattern later, or use it as a stereo microphone (this is the same pattern as mid-side with an omni mid, ignoring the off-axis aspects of an LDC).  A little cypherin’ led to the hookup scheme, and a bench test gave proof of performance.  It’s a tight fit, requires getting different M3 standoffs for the amp boards, and wiring the new 5 pin XLR to the output boards. 

You get dual output with F8 pattern selection.  If you go to cardioid or omni, you get those out the front output, and nothing on the rear output.  Look to the Lewitt LCT-640-TS or Sennheiser MKH 800 Twin manuals for an explanation of usage. 

HPF and -10 work on the front only.  Set to omni, use -10 switch, reverse polarity, and use reverse side to get wide cardioid through the front output.  Use the HPF to change the off-axis response in the lows only. 


before:

proof:

final:

 

[kingkorg]

You can use Townsend Labs software as well, if it's still free for download.

 

[emrr]

Looks like it requires registration.  The Lewitt plug is free, or use faders and polarity. 

 

[kingkorg]

This one worked fine for me. Even though your mic is not like Townsend's i find it to be fun experimenting with applying different emulations, works great with some mics. Especially ribbon model
Download at demo page
https://townsendlabs.com/products/sphere-l22/

Edit:
Sorry, now i see it is not available anymore.

 

[ln76d]

Cool