Noob question: Diodes in parallel, in the same direction?

[aron]

Wow, I guess I tried most of them too, but I can't remember anymore :-(

http://archive.ampage.org/articles/1/fxsb/042485/Seemingly_good_idea_but_anudder_idea.html

[brett]

Hi
A few years ago I posted a circuit called the "fly" (or something similar) because it was an op-amp with about 10 diodes on each side, and looked like a blowfly.  It didn't sound particularly good, despite my enthusiasm.

RE:

If this is true, we can change the Vf of a Ge to that of an LED, but with a different knee curve. Interesting. Would the curve be the same just at a higher voltage?

Usually, "soft" clipping only involves selecting a low Vf, so that the knee is large relative to the clipping level (NB. the "knee" is about the same for all diodes).  So Ge (Vf=0.3) is softer than Si (Vf=0.7) is softer than LEDs (Vf=2 or more). 

But increasing the "knee" by using several Si diodes and resistors means that you can make Si as "soft" sounding as a Ge.
cheers

[R.G.]

I posted the idea of a softening resistor for diode clipping about seven years ago, including a variable clipping circuit for the MXR D+.

I suggested the progressive clipping/shaping about 8 years ago.
http://archive.ampage.org/articles/1/fxsb/042458/Re_Seemingly_good_idea_but_anudder_idea.html

Hey, cool! I'll have to go search the actual date when I put that up. I was guessing. We did some good stuff before the current generation of boutiquers were out of knee pants, eh?

By-crackey!

[Nick C.]

I tried the softness control last night with a pot instead of a fixed resistor. I had read about it before, but trying it out shows just how cool this is. Here's what this novice hears. As I add resistance the distortion goes down and the volume goes up. Kind of like the opposite of a drive control. On the simple mods page it's also referred to as a clipping threshold control which now I understand. Similar to the series diode trick, but now it's variable. I was also thinking that this adds headroom, but we're not talking clean sound. Kudos to all who pioneered this cool control.

Factor in all the clipping tricks you can do with warping, caps, fets, progressive clipping and my brain hurts

[johngreene]

I posted the idea of a softening resistor for diode clipping about seven years ago, including a variable clipping circuit for the MXR D+.

I suggested the progressive clipping/shaping about 8 years ago.
http://archive.ampage.org/articles/1/fxsb/042458/Re_Seemingly_good_idea_but_anudder_idea.html

Hey, cool! I'll have to go search the actual date when I put that up. I was guessing. We did some good stuff before the current generation of boutiquers were out of knee pants, eh?

By-crackey!

Be prepared to waste several hours once you start. 

It's quite the walk through memory lane.

--john