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previous: nic I have an old net schem someplace..... -- 2/13/2003 7:48 AM

Re: High Impedance buffer

2/13/2003 3:08 PM
jon	Re: High Impedance buffer Guys, If you can let me know the HTML stuff to link you with an image on a remote server by clicking "here", I'll draw up a simple high impedance tube circuit for you. I've tried the 10meg grid to ground resistor with no success; what works for me using a 12AX7 is a bootstrap to the cathode. O'Connor has this pretty well outlined in his books...I recall having to tweak values a bit though. I've tried different approaches for the remainder of it; a Baxendall tone stack ala Ampeg Gemini 1 or Magnatone 260/280 works well in there. Certainly warmer than SS to my ear....I do like running this into a SS power amp(typically after a tube outboard reverb circuit) in certain applications, though. HTH Jon

2/13/2003 3:08 PM

jon

Re: High Impedance buffer

Guys,
If you can let me know the HTML stuff to link you with an image on a remote server by clicking "here",
I'll draw up a simple high impedance tube circuit for you. I've tried the 10meg grid to ground resistor with no success; what works for me using a 12AX7 is a bootstrap to the cathode.

O'Connor has this pretty well outlined in his books...I recall having to tweak values a bit though.

I've tried different approaches for the remainder of it; a Baxendall tone stack ala Ampeg Gemini 1 or Magnatone 260/280 works well in there. Certainly warmer than SS to my ear....I do like running this into a SS power amp(typically after a tube outboard reverb circuit) in certain applications, though.
HTH
Jon

Replies:

BoB Re: High Impedance TRANSFORMER -- 2/14/2003 2:52 PM