Topic: at853 HACK pics

[udovdh]

Another idea: Add a single transistor as an output buffer.  This could be either in the mic body or in the battery box.  The output would then have low enough impedance to drive a transformer.

This is similar to the PNP source follower idea that I found?

[spyder9]

Welcome back to Team AT-A-Boys, Nick.  You'll fall back in love with the 853s.   

[Church-Audio]

Its not fixed gain its adjustable from 00-db to +20 db via a gain knob.

Chris Church

Chris (Church Audios) little preamp could be setup to do three wire and give a nice 20db of fixed gain....

[poorlyconditioned]

Another idea: Add a single transistor as an output buffer.  This could be either in the mic body or in the battery box.  The output would then have low enough impedance to drive a transformer.

This is similar to the PNP source follower idea that I found?

I don't know what "source follower" idea you found.  There are lots of simple circuits to do this.  Can you provide a link?

Infact I'm just dissecting an AT822 single point mic that has a simple source follower in it.  You could definitely put transformers on the output of this puppy!

  Richard

[udovdh]

Another idea: Add a single transistor as an output buffer.  This could be either in the mic body or in the battery box.  The output would then have low enough impedance to drive a transformer.

This is similar to the PNP source follower idea that I found?

I don't know what "source follower" idea you found.  There are lots of simple circuits to do this.  Can you provide a link?

sure!

[Church-Audio]

The only problem with the guitar cable FET preamp is headroom or lack of headroom, a guitar puts out an mV signal of around say 40mV. A mic puts out a signal of from 100mv to 2.2volts peek to peek. BIG difference, the FET preamp is based on a FET inside a mic capsule; they are using the same power method. All you are doing is adding a simple gain stage if it is not biased properly will add more distortion.

And remember that you can already have distortion in the first FET inside the capsule that can not be fixed unless you bypass it with an external FET. The only challenge there is shielding because your signal to noise ratio will go out the door when you use an external FET unless you shield the hell out of it.

Chris Church

Another idea: Add a single transistor as an output buffer.  This could be either in the mic body or in the battery box.  The output would then have low enough impedance to drive a transformer.

This is similar to the PNP source follower idea that I found?

I don't know what "source follower" idea you found.  There are lots of simple circuits to do this.  Can you provide a link?

sure!