We all know germanium and silicon behave slightly differently. I was just wondering if anybody has made a fuzz with selemium diodes or copper oxide diodes? I found a post that mentions Edal Industries as the last source of copper oxide rectifiers.

Now to get way esoteric.... how about tellurium?

I thought selenium rectifier had gone the way of the do-do, but a Google Search turned this place up as result #3.

http://www.indiansources.com/insel.htm

Rare earth distortion+es anybody?

Some old light meters and camers have selenium photocells in them, if you shiled them from light they should work as didodes. Plus, if you want to do it the hard way, how about a gelena (lead sulphide) crystal 'cat's whisker'distortion??

I've tried it in a Tube Screamer copy, and it sounded different, but I suppose it could've been defective or something. Not sure if differnt types' diff. apparent sounds will show all the time, but point contact Ge, alloy junction(?) Ge, Si, seem to give a different sound as clippers. I think somebody here also tried actual tubes to pleasing effect, IIRC. Oh, and I think some have tried FETs(Aron?) also.

Dai

Thanks for the info Dai.

I started thinking about all the different semiconductors out there and how limited the pallette of typical distortion diodes is.

Good call the the lead sulphide Paul! A "Cats Whisker" distortion pedal! I love the idea of having to poke around the crystals to set up the diodes.

I wonder how different a selenium solar cell would sound from a selenium rectifier? Then naturally comes the question of what happens when you apply optical bias?

I know there must be germanium phototransistors sitting in a box some place.

Do amorphous silicon solar cells sound any different from normal crystal cells? What about optical bias again?

I know how gallium phosphide sounds (red LEDs), how about all the different LED semiconductors now from IR to UV-B? This list includes...

GaAs
GaAsP
GaP
GaAlAsP
InGaAlP
InGaN
GaN
SiC

or Mercury Cadmium Telluride Photodiodes?

Then we have older technologies like tunnel diodes.... Imagine making the only pedal that relies on quantum mechanics.  

Here's a diode FAQ with lots of neat info INCLUDING A MANUFACTURER OF GERMANIUM TRANSISTORS as well as point contact and gold-bonded Ge diodes.

http://margo.student.utwente.nl/el/componen/diodefaq.html

In the limited range of diodes I've heard so far one thing has seemed, namely the higher the knee, the harder the sound. Selenium comes in at 0.5V and copper-oxide comes in at 0.2V! That's LOWER THAN GERMANIUM!

Hmmmmmmm...........  
"%er

The only place I've seen coppeer oxide rectifiers was in old multimeters (before 1960). Usually you have a back to back pair, looks like two flattish beads with 3 terminals.
Germanium phototransistor? OCP71