Sound Differences Between Silicon Diodes

[phaeton]

Hello!

I was going to become a new member last week, but when I came to diystompboxes.com to register for these forums, it was gone!  Mad props to Aron (and crew?) for getting it all back together.  Anyways, onto the meat....

I'm aware of the differences in sound (and volume) between Ge clipping diodes and Si clipping diodes... However, what about different types and series of Si diodes compared?  I know that the 1N400x, 1N4148 and 1N914s are all designed for different purposes, and each have different electrical characteristics, but does that amount to any appreciable difference in how they sound?

I haven't A/B'd 1N400x in the exact same circuit as 1N4148s (yet) but I notice a certain characterstic or 'signature' of the clipping in circuits that use 1N4001s.  For lack of a better terminology the 1N400x diodes have what I call a "crusty" sound to them.

It could be all in my head though.  *because* FWIW I can't hear the difference between straight and staggered diodes:

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all of the same type when A/B'd in the same circuit with an SPDT.  Yet I see many examples of that and lots of folks talk about asymmetrical distortion.

Thanks for any and all flames and comments.  

-phaeton

edit: Changed the title so it would make more sense 0_o

[phaeton]

No takers?  *sniffle* *sniffle*

[Seljer]

I'm a noob here but theres quiet an apparent difference in my Rat when I'm using 2 1n914s or a 1n914 and a red LED.

[Ethan]

Great question!  I'd also like to know how diff. shockley diodes sound.  
-ethan

[dv8]

It's all a matter of taste.  Different distortion circuits respond to different arrangements of clipping diodes.  Experiment and keep what sounds best to you on your rig.  Try Ge, 914, 1N400x, and leds. Feel free to mix and match, and put as many 2 or 3 on one side and 1 on the side.

Tell us you circuit, and someone will give you some hints.

To me, in a TS-808, a 1N4001 and 1n914 sounds excellent, but in my modded SD-1 there are 1N914 in one half and a 1n914 and Ge in series on the other half.   In the AMZ Overdrive, red LEDs worked better for me.  In the YJM-308, 2 1n914s sounded great.  

If you can't tell the difference try switching between 2 Ge's and 2 LEDs, there should be some notable difference there.

Feel free to experiment, let your ears be the judge.

-brian

[bwanasonic]

Great question!  I'd also like to know how diff. shockley diodes sound.  
-ethan

Racially inferior?*

I think you mean schottky.

Kerry M

* http://www.time.com/time/time100/scientist/profile/shockley.html


...

[phaeton]

What about the Schlockey Diodes?  I've seen those at Radial Shack between the Bias-ply Transistors and Catalytic Capacitors.

[bwanasonic]

What about the Schlockey Diodes?  I've seen those at Radial Shack between the Bias-ply Transistors and Catalytic Capacitors.

;D  ... I think the only Si diodes I have are 1N914s, so those are the only ones I've fooled with. I have experimented with one Si and one Ge in a simple diodes-to-ground clipping function. Next time I order parts I'll get some 1N4148s and 1N400x and drive myself crazy listening for differences when I should be playing guitar

Kerry M

[aron]

test

[phaeton]

test

test?

[MartyMart]

OK, my 2 c's worth about the "sound" - though remember that the particular
circuit and amout of "drive" and "tone" will vary a lot ... !
Ge diodes, such as 1N34A's will "clip" sooner ( lower forward current ) sound a bit softer
and loose you some "level"
Si Diodes ( 914/4148 are very similar ) will "clip" slightly later ( slightly higher forward current )
and sound a little bit "harder" or more "crunchy"
1 X 1N4148 in one direction is about the same as 2 X 1N34A wired in series

1N4001/1N4002 Si diodes clip even later ( higher forward current ) and give a hard "gritty" texture
which I quite like in a TS-9, they will also give you a bit of a level boost, same deal with LED's, for
which I generally use 3mm "plain" red ones.
The forward current readings for red/green/yellow LED's are all slightly different, so experiment !

Hope that's of some use, "describing" sound is such a grey area.... it's tough !

MM

[R.G.]

I don't want to be dismissive of this, but no amount of typing here will tell you much about how they sound to you.

Grab some diodes and get to work subbing them in and testing. Most of us have done something similar. It's time for you to do the same.

[brett]

Hi.
Most people can hear the difference between asymetric and symetric.  I am slightly deaf, but still like asymetric much much more than symetric.

For single diodes:
1.  It's the conduction "knee" that makes diode clipping sound soft. 
2.  The conduction "knee" on diodes is almost identical for all diodes. 
3.  The voltage level of knee (the onset of clipping) varies (ge and schottky lowest, then Si, then LEDs). 

Therefore, the *proportion* of knee is the inverse of the clipping voltage.
Ge and Schottky at 0.3V = soft
Si at 0.7V = medium
LEDs at 2V and more = hard

People seem to confirm this theory in their reports of what different diodes sound like.
cheers 

[MartyMart]

Brett, exactly !
Thanks for a much more concise/accurate explaination
MM.

[Ge_Whiz]

For single diodes:
1.  It's the conduction "knee" that makes diode clipping sound soft. 
2.  The conduction "knee" on diodes is almost identical for all diodes. 
3.  The voltage level of knee (the onset of clipping) varies (ge and schottky lowest, then Si, then LEDs). 

Therefore, the *proportion* of knee is the inverse of the clipping voltage.
Ge and Schottky at 0.3V = soft
Si at 0.7V = medium
LEDs at 2V and more = hard

Hmm. Theory good, but my ears tell me that germanium and Schottky diodes sound very different.

[WGTP]

Yes, that is part of the right-of-passage/initiation here, to experiment yourself silly with diodes.  That is why some quys build pedals with 6-way switches to incorporate all of their favorites.  Don't forget you can also use GE transistors, Jfets and Mosfets(2 different ways). 

I'm still working with diodes and have decided that the different diodes may not sound as different as the RATIO of OP-AMP clipping to DIODE clipping.  For a given level of distortion, using GE's will result in mostly diode clipping (because of the low .3v threshold), but using LED's will result in a lot more op amp clipping mixed with the LED clipping (because of the high 1.8v threshold).

You essentially go from a single clipping stage to a dual clipping stage distortion.  If you have lots of distortion with LED's, lift them and you can hear just the op amp distortion.  IMHO the contribution of the op amp distortion is overlooked many times.  Hope this makes sence.