are there any good CD40106 schmitt trigger drum circuits?

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Iainpunk
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are there any good CD40106 schmitt trigger drum circuits?

Post by Iainpunk » Mon Jun 15, 2020 7:00 pm

hey everyone,

i found 5 CD40106 schmitt trigger ic's in a random assortment IC box on a flea market, they all worked fine, so i decided that i want to use them, are there any good drum circuits using CD40106? i already tried the "metallic noise" circuit, but that sound isn't really to my taste.

i am already experimenting with a snare /clap circuit, which sounds aggressive but nice, but it only uses 3 of the 6 schmitt triggers. i was hoping to find a tom or woodblock circuit to try out.

thanks in advance,
Iain.

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dot matrix madness
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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by dot matrix madness » Tue Jun 16, 2020 2:21 am

If you want to do generate a square wave as input for a twin-T circuit look here:
logic noise: filters and drums
Otherwise the PAia Drum Tone Board has
even simpler circuits (follow the link to "Drum Tone Oscillators" and then "Full Drum Tone Board Schematic"
Licenced to solder since 1993

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JimY
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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by JimY » Tue Jun 16, 2020 3:05 am

As oscillators, they are very much dependant on supply voltage for pitch stability. So dropping the supply voltage drops the pitch and amplitude. Add a capacitor on the chip supply, switch off the power and - instant space drum. Add a variable resistance across that cap, and you can vary the droop/decay time. The output needs heavy low pass filtering. If you add a high impedance buffer, the waveform on the oscillator timing cap is an approximate sawtooth which is a bit more musical and easier to filter.

Iainpunk
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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by Iainpunk » Tue Jun 16, 2020 7:45 am

dot matrix madness wrote:
Tue Jun 16, 2020 2:21 am
If you want to do generate a square wave as input for a twin-T circuit look here:
logic noise: filters and drums
Otherwise the PAia Drum Tone Board has
even simpler circuits (follow the link to "Drum Tone Oscillators" and then "Full Drum Tone Board Schematic"
most of the circuits here use inverters as oscillators, but i want to use the 3 schmitt triggers with the minimum amount of parts possible.
JimY wrote:
Tue Jun 16, 2020 3:05 am
As oscillators, they are very much dependant on supply voltage for pitch stability. So dropping the supply voltage drops the pitch and amplitude. Add a capacitor on the chip supply, switch off the power and - instant space drum. Add a variable resistance across that cap, and you can vary the droop/decay time. The output needs heavy low pass filtering. If you add a high impedance buffer, the waveform on the oscillator timing cap is an approximate sawtooth which is a bit more musical and easier to filter.
that is a great idea!!! the snare doesn't like unstable/varying power, but i can change some circuits around to make it work with envelopes... if i can get that to work, i can even substitute the 555 i used in the snare. i don't mind having to filter the drums, since they are going through a bunch of guitar pedals anyways.

cheers,
Iain

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Eloc
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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by Eloc » Tue Jun 16, 2020 10:37 am

You may have seen this and it may be more of the 'metallic noise' you don't want, but there's some interesting simple stuff in this series of articles:
https://hackaday.com/2015/02/04/logic-n ... or-sounds/
https://hackaday.com/2015/04/10/logic-n ... s-cowbell/

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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by KSS » Wed Jun 17, 2020 11:58 pm

Iainpunk wrote:
Mon Jun 15, 2020 7:00 pm
hey everyone,

i found 5 CD40106 schmitt trigger ic's in a random assortment IC box on a flea market, they all worked fine, so i decided that i want to use them, are there any good drum circuits using CD40106?
Ray of MFOS (RIP) was a big fan of the 40106. Check his circuits. I think Nick Collins also is a 40106 fan. the seamoss site has a few of his circuits, but nothing for drums.

Thomas Henry's The Electronic Drum Cookbook is very good but again has no 40106 -I just checked my copy.

John Simonton's PAIA work was already mentioned.

What is it you want to do exactly? I know you said tom ands wood block. Bugbrand has a few 40106 oscillator cirfcuits.

Did you try pitching the metallizer osc's down quite a bit? Maybe gate them with a 555.

Something along the lines of the CGS Psycho and Super Psycho are I think a good starting point.
Make multiple simple oscillators. Pitch them differently. Combine in numerous ways. It's a powerful technique but one that doesn't necessarily result with instant gratification. Might only need to spend some time adjusting the frequencies and levels to get where you want to go. Pretty much all the best modular stuff lives at the end of that -sometimes- long road! Worth the walk.

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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by KSS » Thu Jun 18, 2020 12:05 am

https://hackaday.com/2015/03/25/logic-n ... and-drums/

This was at the link eloc posted.

FWIW, Lose the XORs if you're after Tom's and wood blocks.

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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by Eloc » Thu Jun 18, 2020 7:10 am

To be honest, I think 95% of the drum circuits using 40106 are going to be 'make 6 oscillators and combine them in different ways'. And as KSS said, you might just need to spend time trying different combinations and pitches: XORs, other logic, gating each other, summed etc etc

CGS Cynare is another example:
https://sdiy.info/wiki/CGS_Cynare_drum_simulator

You can get incredibly varied sounds out of circuits like this, some of which are metallic, some of which aren't. It's all about the relationship of the frequencies of each oscillator, and how they are combined.

Personally I would make a circuit like the Cynare's 40106 section, maybe try swapping out the XOR for other 4000 series logic gates, and experiment with starving the power of the 40106 with an envelope like JimY mentioned, that sounds fun

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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by J3RK » Thu Jun 18, 2020 11:40 am

I don't know about the 40106 specifically, but you might check out some of Phobos' work over at Electro-Music. He's done a lot of simple-but-nice circuits, including a lot of CMOS/Lunetta type stuff as well. You might also check out the Lunetta sub-forum over there too.

One of the first posts that just caught my eye: http://electro-music.com/forum/phpbb-fi ... co_954.png

It's a 40106 saw/trig VCO. You could make a simple saw-tri converter with an op amp and a few passives. Then make a decay envelope. That would be pretty flexible for several types of drum sound.
Are you lemon? Does your head come to a nub?

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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by KSS » Thu Jun 18, 2020 3:38 pm

:agree:

Phobos on E-M is required reading.

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JimY
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Re: are there any good CD40106 schmitt trigger drum circuits?

Post by JimY » Sat Jun 20, 2020 3:46 am

Don't forget the same oscillators work with the CD4093 chips. These have four 2-input Nand gates so one input has the timing resistor/cap and the other is tied to +supply if not used or if taken to 0V will stop the oscillator.
Also, any inverter oscillator can safely be stopped by switching the input to 0v - so you can wire as many oscillators in the chip you want and don't have to have them all running at once.
I actually got a pretty good kick drum going on the breadboard with a 4093 oscillator and envelope supply volts. Extracting a stick/beater sound from the trigger pulse really helped the illusion and is something I would be sure to include however the drum voice is made.

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