Most interesting, versatile diode clipper/ waveshaper in distortion pedal?

[iainpunk]

sound samples!   

for the crossover i don't have an available breadboard, but the wavefolder is ready to go on the breadboard.

i'm not in possession of a cell phone so easy recording is not available, maybe ill record tomorrow with my brothers microphone setup if he agrees to howl his or my stuff over to record.

cheers, Iain

[sergiomr706]

Both of them Will be bjt4558 or jfet op amps? Or os it nota decissive in this case? Thank you

[iainpunk]

i think Jfet op amps like the tl072's work fine for most things if you aren't clipping the opamp, keep in mind that the schematics i gave aren't designed for single +9V supplies, and need a bit of tinkering to even work, creating Vcc/2 (Vbias) and biassing everything is necessary to make it work with single supply's.
i like to use the LM358 because it can work on lower voltages than 9V, four AA batteries give 6V and its easy to make a split power supply with them for +/- 3V. which makes the design and tinkering with waveshapers easier.

cheers, Iain

[sergiomr706]

Thank you, i ll try some

[Steben]

I modeled the batman dist but only got a sine wave with 100mVolts input.



If I stepped the input from 0V to 3V with 1V increment I got this:



What is that red dot in your schematic?

[iainpunk]

I modeled the batman dist but only got a sine wave with 100mVolts input.



If I stepped the input from 0V to 3V with 1V increment I got this:



What is that red dot in your schematic?

the red dot is an not connected node, i forgot to take it out.
it really doesn't like a high impedance Vbias, that's why i use the split supply. try an op amp buffer with the Vbias to lower the impedance
idk how yet, but i can upload the Falstad simulation file so you can simulate it there.
my o'scope also shows wave folding in action! to bad i don't have a camera

sound samples?

i have done some recording with the 'mic in' on my computer and a headphone amp that sound quite alright, where do i upload the sound clips to share them here?

cheers, Iain

[iainpunk]

here are some sound samples
https://soundcloud.com/iain-schmaloer/sets/batman-distortion-wavefold-fuzz
cheers, Iain

[Vivek]

https://www.premierguitar.com/articles/adjustable-clipping-in-vox-amps-1

Studied by the guru RG Keen

[teemuk]

The Thomas Organ circuit simply increases clipping threshold by referencing diodes to a higher DC voltage potential than 0 volts. We could draw it much simpler without the surrounding gain stages, resistive dividers generating the reference, and by using positive and negative voltage references requiring no further resistive voltage division. There would simply be one shunt diode and 100R series resistor connecting ca. +200mVDC and another similar but antiparallel string connecting to -200mVDC.

Pretty boring circuit really.

Let's raise the stakes and make those DC references dynamic instead of fixed. For example, imagine what happens if we subtract rectified and envelope-followed input or output signal from that DC reference... yes, we get lower clipping threshold for higher input amplitudes and higher threshold for the lower ones. These thresholds would shift dynamically in accordance to overall signal dynamics. "Simulated sag".
..Or, for example - implemented to a power amp - we could downscale the high DC voltage supply rails that sag under current draw and acquire a similarly sagging clipping threshold in the diode circuit. Now a power amp designed to have its clipping point just slightly above peak input of the clipping limiter would not overdrive when its power rails sag, because peak limiter would decrease its threshold accordingly.
..Or we could just hook up the reference to an LFO and produce some intermodulation harmonics for very weird distortion effect.

[Vivek]

Sir Teemu K,

I was thinking of the same thing, of modulating the DC bias voltage based on the envelope of the signal, to get time variant harmonics.

[iainpunk]

if you like changing overtones, listen to some ot the sound samples with higher numbers, that's maybe an extreme example, but you might like it
https://soundcloud.com/iain-schmaloer/sets/batman-distortion-wavefold-fuzz

cheers, Iain

[Vivek]

At some points on the Batman, if felt there was a sudden increase in volume as the chord was dying down.

[Vivek]

DFG

[Steben]

DFG

I guess that would be rather more comfortable with a 18V supply?

[iainpunk]

At some points on the Batman, if felt there was a sudden increase in volume as the chord was dying down.

that is correct!!!! because when the clean wave goes negative and gets folded, it then gets clipped again at the 0V point, the volume dies down when there is enough input since the area under the wave determines the perceived volume, and it rises back up when the signal gets smaller. because less gets ''flatted out'' by the clipping

the hardest thing about the circuit is to get it sounding just right that you dont get too much ''sag'' and not too little of the ''clean side''. its also quite hard to get it to clip exactly in the middle, although that is not that big of a deal, sound wise.

cheers, Iain