Germanium diodes with bias.

[wa2ise]

Originally Posted by catman

...

Last night though I tried a experiment with using bias with conventional gernmanium diodes (I used an old GEX34 germanium diode), and the results were interesting.

Germanium diodes almost don't require bias due to their inherently excellent 'sensitivity', but the addition of bias (when correct bias is applied), reduces overall audio distortion and the germanium diodes have a nice 'rounded' sound which is quite pleasant to the ears.

...

I did something similar on an AM/FM/police band radio.
I had to make the biasing switchable, as the radio used the AM detector circuit as a bias circuit for an FM IF amp transistor. I adjusted my R1 to counteract the bias circuit and to get the diode in a nice detection range for weak stations.