[Boatanchors] HeadWize - Project A Zero-Feedback SRPP-Input Headphone Amplifier by Simon Busb

[J. Forster]

William L Howard wrote:

> I recently ran across an article on a headphone amplifier at this url
>
>  http://www.headwize.com/projects/showfile.php?file=busbridge_prj.htm
>
> I am wondering if this could be made with three tubes rather than the  2
> 1/2 sections of the tube that was shown.

Sure, but why?

> I also wonder if this could be used with an RF amp, detector stage, 1 audio
> and then this three tube
> set up?

By my count, 1 tube RF amp, 1 detector, three tubes here, 1 rectifier...  that's
enough to build a superhet which will perform far better.

BTW, 'no feedback' is not correct. The design has a cathode resistor in the
cascode stage and another in the output stage. Each provide negative FB.  What's
wrong with FB anyway, as long as it's properly designed an is stable. It
improved linearity, bandwidth, and lowers output impedance. Marantz and McIntosh
used it extensively.

FWIW,
-John