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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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Posted: Tue Jun 15, 2021 11:50 am Post subject:
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The first image is the original waveform with the second stage added at full gain and delay. The rest of the images just add another stage to the previous image with full gain and delay. The difference between odd and even numbers of stages is interesting.
p.s. these images are in reverse order. oops!
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Last edited by NuttyMonk on Tue Jun 15, 2021 11:55 am; edited 1 time in total |
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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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Posted: Tue Jun 15, 2021 11:53 am Post subject:
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Here are some more waveform images which are just me mucking about with the gain and number of stages. I left the delay at maximum on each stage so it is easier to see what is going on.
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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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Posted: Tue Jun 15, 2021 1:09 pm Post subject:
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p.s. there are errors in the schematic. The power supply of U3.7 on page 1 should be +12V, not -12V and on page 2 the resistor going to Jack4 should be 1k not 100k.
Also, i wonder if i could get CV control for the delay and gain of each stage. |
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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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Steveg
Joined: Apr 23, 2015 Posts: 182 Location: Perth, Australia
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Posted: Tue Jun 15, 2021 5:53 pm Post subject:
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It looks to be a combination of two fairly well known techniques. The first is a low pass phase shift process that is usually used for CMOS frequency doublers an the second is mixing alternate normal and inverted waveforms used in analog wavefolders or waveshapers.
That said I haven't seem them used in combination so it looks like you may have something unique (but that may just mean my reading list is too short).
I also looked at longer chains of lowpass filter ->schmitt triggers as a possible way to make a lunetta grade chorus but I never got around to building anything. |
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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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Posted: Tue Jun 15, 2021 6:03 pm Post subject:
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Thanks Steveg.
what about the waveforms themselves. There are 6 stages with 6 gains and 6 delays each, all controlled with pots. The possible variations seem to be very large judging from the little bit of messing around i've done so far.
The output is fairly low level, about 4V Peak-to-Peak so it needs a decent amount of amplification and the waveform always has a large DC offset too but hopefully my setup will be ok at dealing with those issues.
Cheers
NM |
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Steveg
Joined: Apr 23, 2015 Posts: 182 Location: Perth, Australia
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Posted: Tue Jun 15, 2021 6:21 pm Post subject:
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The waveforms look interesting. Proof of the pudding is what they sound like
And that all depends on what you want to hear. They certainly won't be boring square waves any more. |
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blue hell
Site Admin
Joined: Apr 03, 2004 Posts: 24083 Location: The Netherlands, Enschede
Audio files: 278
G2 patch files: 320
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Posted: Tue Jun 15, 2021 6:39 pm Post subject:
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Hah, it seems to be unique enough to me, as in that it is a cool idea that you (or me) never had before
Patentable, I guess not, like Steveg suggests ... but I think it is worthwhile to try out ideas, to not be afraid of failures.
I've no idea if it would be interesting sound wise, but hey, you can always put a filter after or some effects .. the graphs show a richness in overtones that could be very interesting .. but also ... about the inharmonics .. when you tune the delays it could be very harmonic .. look at the delay times .. reciproce them .. as in 1 / delay ... and that will give you a tool to tune it I'd think?
But hen again people also spend time on inharmonic stuff to get a perfect highhat and things like that.
From the schematic I can see you tried to generalize the idea in a nice way, I'd explore it _________________ Jan
also .. could someone please turn down the thermostat a bit.
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Cynosure
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Joined: Dec 11, 2010 Posts: 966 Location: Toronto, Ontario - Canada
Audio files: 82
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Posted: Fri Oct 15, 2021 8:29 am Post subject:
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This seems cool. It reminds me of a couple of other Lunetta circuits. You could make similar waveshapes with the old trick of running a 4017 at audio rate, sending each output through a pot, and mixing all of them together.
How "perfect" is that saw wave? Does shape or amplitude change with frequency?
Let's hear some audio demos! _________________ JacobWatters.com |
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Cynosure
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Joined: Dec 11, 2010 Posts: 966 Location: Toronto, Ontario - Canada
Audio files: 82
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Posted: Fri Oct 15, 2021 10:09 am Post subject:
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Steveg wrote: | I also looked at longer chains of lowpass filter ->schmitt triggers as a possible way to make a lunetta grade chorus but I never got around to building anything. |
I did a cmos delay with shift registers. You could probably make a chorus with it too.
https://electro-music.com/forum/topic-57022.html _________________ JacobWatters.com |
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NuttyMonk
Joined: Jun 30, 2020 Posts: 62 Location: UK
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Posted: Fri Oct 15, 2021 11:47 am Post subject:
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Hi Cynosure,
I've never actually breadboarded it yet. It was just a by-product of me mucking about in Falstad and trying to get phase shifts and delays. Also i was trying to find uses for all 6 inverters on a CD40106.
I'm still in the stage of getting some basic modules built up. May be a while before i get around to this. If you have breadboard space and the components for it, feel free to give it a try for us.
Cheers
NM |
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