4070 IC--exclusive OR gate synth?

[Dr. K]

Hello,
Hope everyone is staying healthy...

I stumbled upon an interesting HackADay article about using a 4070 XOR gate for making cymbal and cowbell-ish sounds. https://hackaday.com/2015/04/10/logic-noise-more-cmos-cowbell/

I'm wondering if anyone can suggest some 4070 circuits to play with? I have a bunch of oscillator chips that i can use to feed it--555/556s, 4093s, 40106s... I recently built a simple sequencer...

I also have some 4040 chips, so could do some frequency mixing with that too.

Check out the first Youtube vid on the Hack A Day link. The last 20s or so is pure electronic chaos. It's really an interesting idea--pumping out sums, differences, and then a lot of artifact frequencies from 2 input wave forms.

Of course, nothing is open so I put in an order for components. It would be good to read up on it in the mean time. I could be working from home for some time before this blows over!

Hope everyone is staying well! Thanks for any input about XOR gates and synthesis!!

[PHOBoS]

http://electro-music.com/forum/post-333061.html#333061

and you will probably run into them if you check the lunetta section.

(I am a bit tired and lazy right now)

[RingMad]

Yeah, the Logic Noise series of articles on Hackaday is really cool. The author took inspiration from some of the stuff in the Lunetta subforum here on electro-music.

Indeed, PHOBoS' link to his XOR Stereo Droner circuit is a cool circuit... I built a little box using it.

One can also make a pseudo-random bit generator which is an implementation of a LFSR (Linear Feedback Shift Register)...
http://electro-music.com/forum/topic-52066.html

I could have sworn I already posted the XOR Chain circuit on the forum before but I can't find it, so I'll put it here. I found it years ago from the long-defunct The Sound of Logic forum (I think) on a different site. It was by ezekiel and implemented the cellular automata Wolfram rule 90.

There are loads of "fake ring modulator" using XOR circuits out there.

You should be able to find more circuits doing a search here on XOR or 4070 and selecting the DIY Hardware & Software subforum, or even more specifically the Lunetta one.

Feel free to list them here with links... that could be a good resource for those fascinated with the XOR. Re-reading the hackaday post made me want to build something new... but I already have a backlog of projects.

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[blue hell]

Rule 90 is a nice one

[PHOBoS]

yeah, I've seen that XOR chain before and hardly ever visited the Sound of Logic forum, but might have seen it there.

Another thing XORs are useful for is as a controllable inverter. Send a (digital) signal into one input and if you make the other input
high it will act as an inverter, otherwise the signal will pass straight through. If you add XORs to the outputs of a binary counter you
can use this to change the count direction (up/down).

[Dr. K]

wow, all very cool ideas!! that ring circuit looks like a recipe for electronic madness.

I just put a hefty order for components in, including 2 more breadboards.

Also, since I've been torturing my SO with electronic mayhem during the pandemic, I spend an hour today installing a headphone jack in my amp

It will be fun to mess with this. I'm still trying to learn about Lunetta synths, and am hoping to build some modules. I have some interesting stuff already built, and also just finished a basic sequencer. So far, it's been a fun project, all boxed up in cool project boxes.

I think coupling these XOR devices with basic 40106 and 555 square wave osc. will be an easy to implement strategy. The 555 circuits, especially, where i can tie them directly with the sequencer. Fun fun! Should be an interesting project. Thanks for the ideas. I'll make sure to document any successes and share them. This is a cool forum for exactly that reason.