tgergo
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Post by tgergo on Dec 5, 2021 21:41:46 GMT
Hello there, I'm wondering what module and/or technique I could use to generate variable length gate signals from triggers? I VCV Rack I use a Bogaudio module called RGate. My requirement would be: * gate is opened trigger pulse * gate stays open for the time set by a length parameter * length parameter should be voltage controlled * the primary purpose would be to send the gate signal to an envelope generator |
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Post by admin on Dec 5, 2021 22:29:31 GMT
Hi and welcome to the forum!
Having a gate with voltage controlled length is a great idea, something that I am dearly missing when trying to control the 3VCSWITCH.
At the moment this kind of module doesn't exist for AE, the closest you would get is with the 2ENV which has VC controlled attack and decay stages, but it's not a true gate if you need constant 5V when open.
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Post by pt3r on Dec 6, 2021 6:48:52 GMT
Have a look at the bernouilli gate firmware for GRAINS, by duddex, that could be easily modified to do exactly what you describe. You will of course always have to define upper limit i.e. what does 5v correspond to in gate length? 1 minute? 5 minutes? half an hour? |
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tgergo
Junior Member
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Post by tgergo on Dec 6, 2021 8:37:56 GMT
Isn't the monostable mode of the 555 timer IC something similar? Changing the fixed resistor to a variable one would already give us manual control over the gate length. Then the only thing left is to somehow safely feed in the control voltage on top of that. Or am I wrong? |
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tgergo
Junior Member
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Post by tgergo on Dec 6, 2021 16:30:23 GMT
 I'm thinking of something like this. I'm not sure how one would add the control voltage as input. |
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pol
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Post by pol on Dec 6, 2021 19:30:42 GMT
Have a look at the Wonkystuff RBSS, has variable gate length but not necessarily under the user's control...
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pol
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Post by pol on Dec 6, 2021 19:32:53 GMT
It also occurred to me you may be able to do something like what you want with the ADSR module as it as VC sustain level, or maybe use the VC Decay or release to give different lengths of sound....
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Post by thehatghost on Dec 7, 2021 0:20:18 GMT
Could the Trip module do this? It takes a clock trigger and has an adjustable gate time… if the repeats are set all the way down maybe?
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Post by keurslagerkurt on Dec 7, 2021 7:49:24 GMT
View AttachmentI'm thinking of something like this. I'm not sure how one would add the control voltage as input. I like your thinking. This circuit basically has voltage control already: the pot is used to dial in a voltage at pin 6 and 7. You could use An op-amp adder/summer circuit to add the the pot voltage together with an external CV voltage. Would you mind sharing the falstad txt/link/.. file? That way i can try to modify it to show you 😃 might be a good start for a thread on the DIY sub EDIT: i was on phone and thought it was a Falstad software circuit, but it's not, sorry! Nevermind my question then 😉 |
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tgergo
Junior Member
Posts: 59
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Post by tgergo on Dec 7, 2021 8:47:01 GMT
I like your thinking. This circuit basically has voltage control already: the pot is used to dial in a voltage at pin 6 and 7. You could use An op-amp adder/summer circuit to add the the pot voltage together with an external CV voltage. Would you mind sharing the falstad txt/link/.. file? That way i can try to modify it to show you 😃 might be a good start for a thread on the DIY sub EDIT: i was on phone and thought it was a Falstad software circuit, but it's not, sorry! Nevermind my question then 😉 Thank you for the feedback. I see 2 missing pieces at the moment: * adding the external voltage to the dialed in voltage (Thank you for the hint here, I had no idea how to do that. I have very limited knowledge about electrical engineering.) * negating the pulse signal (I think a the moment it would need to be high all the time and a low pulse would trigger the gate generation.)I was already starting to think I should take this to the DIY section. I'll do so. I will also take my draft to falstad. I hope that makes it easier to share and maybe get some improvements. |
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Post by keurslagerkurt on Dec 7, 2021 9:27:10 GMT
Thank you for the feedback. I see 2 missing pieces at the moment: * adding the external voltage to the dialed in voltage (Thank you for the hint here, I had no idea how to do that. I have very limited knowledge about electrical engineering.) * negating the pulse signal (I think a the moment it would need to be high all the time and a low pulse would trigger the gate generation.)I was already starting to think I should take this to the DIY section. I'll do so. I will also take my draft to falstad. I hope that makes it easier to share and maybe get some improvements. Both points will be fixable with minimal components I think. I think it will even be a great circuit for learning some essential EE stuff without getting too complicated. I learned 99% of my EE also on youtube, synth diy and forums like this one  * External voltage: opamp summer circuit should do the trick. * Pulse signal: what you are after is an inversion of the pulse signal (LOW -> HIGH on the CV input, but HIGH -> LOW on the 555 pin). There are a lot of ways to do this, but a classic synth input stage would use a transistor switch for this. Another interesting option might be using an opamp as comparator in inverting configuration. Opamps always come in at least dual packages, so you'll have a spare one because the first point here has to use an opamp. If you draft the circuit in Falstad & post it in the DIY section, I'll happily adjust it with what I think will work. And then everyone can play around with it as well! No stress of course. But I think this can be a fun circuit that might even be doable on the brAEdboard module! |
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tgergo
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Post by tgergo on Dec 7, 2021 10:17:54 GMT
The module design lives in the DIY section now.
Thank you very much for the suggestions about other modules too that can serve this purpose. I have an RBSS on the way and that is potentially what I need since I'm thinking of generative gate signals with some random variation. I'm also interested in buying a Trip module for its main features anyway. I also like the Grains idea. I have both an arudino and an esp32 lying around but getting the grains module might be a good incentive to actually do something on the programming side of things.
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Post by keurslagerkurt on Dec 7, 2021 11:36:08 GMT
The module design lives in the DIY section now. Thank you very much for the suggestions about other modules too that can serve this purpose. I have an RBSS on the way and that is potentially what I need since I'm thinking of generative gate signals with some random variation. I'm also interested in buying a Trip module for its main features anyway. I also like the Grains idea. I have both an arudino and an esp32 lying around but getting the grains module might be a good incentive to actually do something on the programming side of things. If you want to check out Grains, you can make a grains on a breadboard if you have an arduino nano laying around. |
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tgergo
Junior Member
Posts: 59
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Post by tgergo on Dec 7, 2021 12:11:00 GMT
The module design lives in the DIY section now. Thank you very much for the suggestions about other modules too that can serve this purpose. I have an RBSS on the way and that is potentially what I need since I'm thinking of generative gate signals with some random variation. I'm also interested in buying a Trip module for its main features anyway. I also like the Grains idea. I have both an arudino and an esp32 lying around but getting the grains module might be a good incentive to actually do something on the programming side of things. If you want to check out Grains, you can make a grains on a breadboard if you have an arduino nano laying around. I'll give that a shot too. I have found this searching in DIY. forum.aemodular.com/thread/699/diy-grains |
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Post by keurslagerkurt on Dec 7, 2021 12:20:03 GMT
If you want to check out Grains, you can make a grains on a breadboard if you have an arduino nano laying around. I'll give that a shot too. I have found this searching in DIY. forum.aemodular.com/thread/699/diy-grainsI personally did it only on breadboard, following that schematic on the AE Wiki page. For the filter block I used an RC-filter with R = 1k and C = 100nF. (Connected at the output like in this calculator: sim.okawa-denshi.jp/en/CRtool.php ). Worked out for me! |
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tgergo
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Posts: 59
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Post by tgergo on Dec 23, 2021 16:32:52 GMT
I have found that the ADSR module can be used for gate generation if you set the GT/TRG switch to GT. A trigger pulse will raise its output signal to high according to the Attack setting and a second pulse will send it low according to the Release setting. With A and R turned all the way down and Sustain turned all the way up, this will produce a gate. It can be sequenced with something like the MM-DIV, the TRIQ164, or a random pulse that could be produced with a looping ENV and the NOISE + S&H hooked up to the A and D inputs.
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Post by pt3r on Dec 23, 2021 17:32:04 GMT
I have found that the ADSR module can be used for gate generation if you set the GT/TRG switch to GT. A trigger pulse will raise its output signal to high according to the Attack setting and a second pulse will send it low according to the Release setting. With A and R turned all the way down and Sustain turned all the way up, this will produce a gate. It can be sequenced with something like the MM-DIV, the TRIQ164, or a random pulse that could be produced with a looping ENV and the NOISE + S&H hooked up to the A and D inputs. Great tip. pol is this something for the wiki? |
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pol
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Post by pol on Dec 23, 2021 20:29:09 GMT
I have found that the ADSR module can be used for gate generation if you set the GT/TRG switch to GT. A trigger pulse will raise its output signal to high according to the Attack setting and a second pulse will send it low according to the Release setting. With A and R turned all the way down and Sustain turned all the way up, this will produce a gate. It can be sequenced with something like the MM-DIV, the TRIQ164, or a random pulse that could be produced with a looping ENV and the NOISE + S&H hooked up to the A and D inputs. Great tip. pol is this something for the wiki? If I understand correctly this correctly I'd say yes! |
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pol
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Post by pol on Dec 23, 2021 20:40:04 GMT
I have found that the ADSR module can be used for gate generation if you set the GT/TRG switch to GT. A trigger pulse will raise its output signal to high according to the Attack setting and a second pulse will send it low according to the Release setting. With A and R turned all the way down and Sustain turned all the way up, this will produce a gate. It can be sequenced with something like the MM-DIV, the TRIQ164, or a random pulse that could be produced with a looping ENV and the NOISE + S&H hooked up to the A and D inputs. The wording on the Wiki page for the Gate/Trigger switch was a bit wooly/vague. I have reworded as per what I think you have said here,  I'll have to go try it myself but won't be for a few days as some event is happening... wiki.aemodular.com/pmwiki.php/AeManual/ADSRCould you confirm correct please. Pol. |
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tgergo
Junior Member
Posts: 59
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Post by tgergo on Dec 24, 2021 8:08:50 GMT
Hi pol, I was trying to reproduce this for a track and hold demo with the 3VCSWITCH, but I can't. Currently the only thing I can imagine is that I used the ADSR triggered by with a high pulse width square LFO output and that's what confused me. I'm not sure. |
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tgergo
Junior Member
Posts: 59
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Post by tgergo on Dec 24, 2021 9:05:09 GMT
I'm still confused what I got wrong here, but I have another one that actually works with both the 2ENV and the ADSR. I tried with both in trigger mode. Send the END output to the 2CVTOOL to invert it with 0 offset. When the module receives a trigger the inverted output coming through the 2CVTOOL will be sent high. The length of the high gate signal will be determined by the A, D and the fast/slow setting of the envelope generator.
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pol
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Post by pol on Dec 30, 2021 20:51:43 GMT
Hi pol , I was trying to reproduce this for a track and hold demo with the 3VCSWITCH, but I can't. Currently the only thing I can imagine is that I used the ADSR triggered by with a high pulse width square LFO output and that's what confused me. I'm not sure. No worries, I'm going to spend some time editing the Wiki this weekend and horrors, may even play with the AE myself and check out more about the ADSR module - it's one of my favourites anyway, |
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I'll have to go try it myself but won't be for a few days as some event is happening...