DC coupled condenser / fetless electret mic amp circuit

The THAT1510 just requires +15 V and -15 V. In fact anything between +5 V ... +20 V, -5 V ... -20 V is guaranteed to work, but the specifications apply at +15 V and -15 V.

The +48 V is probably meant for a phantom supply for the built-in preamplifiers of professional condenser microphones.
 
in the on / off part of the circuit they pull in+ and in - up to +48v. now granted that's through a 6.8k resistor on both sides, but that seems significant. If I float that connection do you think it would still be "on". I don't see why not, but then again I don't know why they have it pulled up to 48v either. pulling down to ground to turn it off makes sense, but pulling it up to 48v doesn't.
 
48 V and two well-matched 6.8 kohm resistors is the standard phantom supply circuit for professional condenser microphones. One would normally turn it on when using condenser microphones and off when using dynamic microphones. The THAT1510 works with and without it.
 
So they forgot the giant hole in the center .......
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well the adapter I bought that was supposed to break out the microphone from the usb-c side channel did not work. it was supposed to be a charge and headphone/mic cable, but it didnt even pass through 5v ...

Plugging a usb-c cable directly in and soldering jumpers to the ac_decoupled out and ground gave me some audio, but I don't have the emi filter in place yet so the auto gain was all over the place while it was fighting with radio signals. hopefully tomorrow I can get an emi shield in place
 
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So this is kind of part of a larger project and to get the full scope I'll have to start at the beginning with my headset. I bought the Fostex T60RP s.
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stock ear cups vs the Xenon Pads from modhouse audio
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Replaced the stock strap with the deerskin one from modhouseaudio
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insert Yak Down

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This paracord color is called argon
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Made some custom cables
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stock baffle
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vs polymer clay with tungsten dust and tungsten granules

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Replaced the stock 2 conductor cable with a 4 conductor (doubled up) of heavier gauge and I think it also looks cooler
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stock 3.5mm unbalanced jack
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vs 4.4mm balanced pentaconn jack

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I was in and out of those headphones so often tweaking things I eventually started to strip out the wood so I added threaded inserts

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I promise this will make sense here in a moment
 
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Some laser cut parts for the microphone boom
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Going to hinge it together something like this
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So here is how the mic and the headset are related
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in the first picture the screw heads haven't been counter sunk yet, the edges haven't been rounded off, it hasn't been cleaned up. just finished enough for a test fit

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Still haven't cleaned it up in this pic, but you can see how it will mount and be able to slide up and down for adjustment
 
bent some brass plate into a circle to encapsulate the brass EMI shield and serve as a solder point for the 12 brass rings that will facilitate the shock mount which will be bungie cord between those rings and the holes in the circuit board. the top right shows one of those shock mount rings. still in rough shape
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