SDIYClass#2 - The 3 dollar LoPass Gate - Make your own Vactrol!
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- เผยแพร่เมื่อ 9 มี.ค. 2017
- A short tutorial on making your own Vactrol, then using it to make a simple but effective passive Low Pass Gate in the West Coast style. Thanks Don Buchla for inventing this way back :)
Roman Sowa brought my attention to a mistake I made: " LEDs do not have any lag, they are as fast as lightning. You cannot see short blink because your eye cannot see it, not that LED have not emited the light. It's the LDR what brings that lag." Thanks Roman!
Here's a cool thread about this for some more ideas! www.muffwiggler.com/forum/vie... - เพลง
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I made one to be a Bastl Kastle friend. Immediately great, thanks for the tutorial!
Thank you very much :-)
With your help I made my first passive low pass gate and it sounds pretty much the same as my Meng QI DPLPG.
I was a bit worried about the DIY vactrol but it works :-)
cheers
andy
hey o7, wanted to thank you for this vid......VERY MUCH!! i'm getting into building basic oscillators and noise circuits, and this circuit is so so legit, FUN and easy to make. I have been putting it on the output of everything lately and using the bastl cv trinity to send the vactrol rhythmic lfo's and envelopes. it works perfectly and sounds so soft, plinkety and analog. with a little fiddling with different leds and resistors it was pretty easy to get the cv voltage from trinity knob range, scaled to match the vactrol volume range. i really appreciate this revelation, because i really wanted some kind of simple envelope to tame and make useful the constantly ringing oscillator swarms...lol and this comes with an added bonus of lowpass filter too which has a very natural sound and can take the buzzing edge off the diy square wave oscillators. the trinity can send exponential shaped envelope cv, and this circuit responds well, making it really nice for shaping the constant input into sweet percussion sounds. but anyway, thanks again. would love to see more vids like this. (maybe the simple transistor ring modulator/waveshaper/bipolar vca one. it's passive too and uses one transistor and three jacks.) anyone considering trying this, SHOULD! : ) this vactrol is extremely useful and has made hours of experimenting with basic circuits pay off, because suddenly it has all become very controllable, musically useful and is really inspiring to use this circuit to perform different types of controlling. 🙋🏻🎛🎛🎛🐛
Hey, this makes me very happy :) It's what makes me want to keep doing this more than anything, thanks for your encouraging words, and keep on having fun with sound and electronics!
Well, I was going to make my first Atari punk console this weekend, but you just changed my plans..lol..thanks for sharing your knowledge mate!
Many thanks for a well produced, interesting and useful video. Having watched it I've been enjoying experimenting with various LDRs, LEDs and resistor values. I'm getting some very passable results so a few of these will find their way into my modular. The main thing I've struggled with is keeping all of the light out. It's amazing how sensitive the LDRs are to very low light levels. I'll get hold of some heat shrink - at the moment I'm using black insulation tape and the light does like to find its way in! Really good cheap additions to my synth though - thank you
cool! yeah, the heatshrink does a way better job than tape, go for it!
another amazing video! the score and the gentle reverb on the voice audio are really great, too
Thanks for noticing the small details :)
Oh my gosh! I think I'm gonna get into DIY now haha. That sounds amazing, and doesn't look like it's too unmanageable. Thanks for the inspiration, subscribed! :-)
Welcome to the desert of the real :D
man you are great,gonna watch all of these videos
Really great video and the results are amazing.
Thanks Mike :)
Excellent video , and very well explained . I may give this a go sometime in future. :-)
very cool mate! I did on one project last year
love the reverb and the synth chirps, makes the whole thing easier on the ears and less boring
Thanks Kamal!
omg thank you so much!
my diy vca until now was just any transistor this sounds way better ;)
but i've got a quite high volume drop
hey, glad it was useful! if you get too much volume drop, skip or reduce the resistor before the LED ;)
Thanks man. Very helpful 👍
Just found a universe of great ideas. Liked and subbed of course
👍🎹🖐
Thank you!
I ordered some mini PCBs for a design similar to this. I'm going to make my own vactrols tonight. Hopefully it works.
Just found your channel, good stuff!
I'm trying to get into more hands on, DIY side of synths with zero previous experience, stressful but rewarding...
You'll get addicted, it's so much fun!
It seems so... gets the brains ticking...
hat's pretty cool! i never knew that combining an LED with a photoresistor was called a vectrol! i used to do that for fun making vibratos on inverter oscillators :D
Vactrol, yeah! Don Buchla used them a lot on his synths :)
Yup old guitar amps used something like that for a Tremolo and or Vibrato.
Really dope, going to try it! thanks :)
Cool, have fun!
@@QuincasMoreira any place you recommend to buy parts? I was going to go on Mouser
Triangle Wave Records I buy at Mouser. Expensive but great quality, service and speed
I love it. It should change the result with the brightness of the led, so it basically changes with the resistor that we choose. How did u choose your res?
I stumbled upon an old article int the electronic magazine from the early 80s, where not the LEDs, but the 12V miniature incandescent bulbs were used. What's interesting, the author recommended to use a kind of diaphragm between the bulb and the LDR. It was a piece of cardboard, painted black, with a teeny-tiny hole in the centre, like in the ancient _camera obscura_ . The diameter of this hole had to be selected EXPERIMENTALLY for the best result. I wonder if it only makes sense with a bulb or...?
yes, that's a way to reduce the light, with LEDs you can simply increase resistance and achieve the same. Incandescent bulbs are much slower than LEDs though, which is why we use LEDs nowadays.
Thanks' for posting.Very nice,easy device!Definitely has that "Buchla, plucky-sound".Love it! : )
Cool, enjoy!
Really useful video! How much is your CV range in volts? Especially max V? Thanks!
Thanks for this simple tutorial. just getting started and it's super clear. Do you know if it would work for adding CV inputs to a guitar effect? I'm trying to hack my Robert Keeley compressor, and turn it into a module. Thanks again!
Maybe. I've never had much luck with vactrols and from my reading/experience this video gets a number of things wrong. When working with audio frequency the limiting factor is the response time of LDR not the LED. For a discussion on LED rise/fall times see this link: forum.arduino.cc/index.php?topic=210864.0 . LED rise times vary depending on colour from ~3 to ~13ns and fall times from ~12 to ~3ns so time worst case rise/fall ~40kHz. If you look at the data sheet for the LDR part number GL5528 (all the GL55xx) the response time rise and fall is 30ms so the maximum frequency with a GL55xx is ~16Hz. An other thing to consider is that if the LED is too bright the LDR will saturate and the is going to increase the fall time. Having said all that LDR's are being use to build guitar effects th-cam.com/video/NHu0szLyr9U/w-d-xo.html
Brilliant, subscribed.
Does adding the capacitor in the output means that this LPG will not pass CV or DC?
Hi, thanks! No, the cap just makes it roll out some high frequencies, it's what makes it an LPG, not just a voltage controlled resistor :)
A DC blocking cap would be in series with the output.
Very nice work - what type of LDR did you use for this? Also, have you done any measurement regarding the amount of time lag you get in the response? How long does the gate stay open once the LED goes off etc?
Thanks Gary! I just used a small LDR I had in my drawer, I'm pretty sure it's 2M max resistance. No, I didn't measure the lag, just by ear, sounded good to me :)
amazing :)
Really dig your stuff
Do you think you could do a vid on the cem3320?
Thanks! Check out my review of the Erica Synths Multimode VCF, it's based on the 3320 :)
Hi! Electronics beginner noob here. First off, thank you for a very useful and very well-explained tutorial.
I was wondering, what if I were to add a potentiometer to attenuate the cv input. Would I be ok connecting the side pins to cv in signal and ground and the middle "viper" to the resistor -> led-ldr combo +. Maybe this is a stupid question but I'm only taking my first baby steps in this thing.
Happy if you can help, anyway thanks again for the tutorial.
Hi Ville, thanks for watching :)
Yes, you can add an attenuator for the CV input if you like, and how you describe it should work just fine! Good luck :)
Synth Diy Guy great thank you again!
Nice video Quincas, thanks for sharing. How significant is the volume drop from input to output when your vactrol is fully open ? I like the idea of a passive device, but wasn't sure if a make-up gain stage would be beneficial, or not really necessary
Hi! I haven't measured, but the volume drop is not very significant, the
ldr resistance goes very low when the LED is fully lit. Besides, synth
levels are so high, it's normal to have to attenuate them, so I don't
really think make up gain is necessary. Thanks !
Awesome, thanks! I'll have to rummage around in my junk pile and find a couple LDRs.... now where did I put those rusty old solar walkway lamps?!?
nice!
A lil' off-topic. :) How to make music which can be heard in the background of this tutorial (starting @0:09)? I believe I also heard this kind of sparkling sounds on Kaitlyn Aurelia Smith recordings... Are here the vactrols involved?
Hi! That was done by using random voltages to generate random melodies with the Make Noise 0 Coast synth. Kaitlyn is a Buchla player and coming from the West Coast school, so I'm sure she uses a lot of random voltages and lopass gates too :)
Interesting video even corresponding to another DIY build.. The Erica Synth SWAMP, would you use DIY vactrols in this module?
hey thanks! Yes, you can definitely try home made vactrols on builds requesting industrial ones. Buchlas use LED/LDR pairings in their synths, no industrial vactrols... Your mileage may vary of course, as different combinations will yield different results. I made my own vactrols for a Thomas White LPG and it worked great!
@@QuincasMoreira i just complete the kit build making my own vactrols and replacing one component, the red 22nf film cap, with 47nf film cap. This cap is connected with one leg of the S&h IC. It actually works fine similarly to your in the kit review.. Vactrols look like a new horizon for me into next builds like arduino cv controlled synths and so on.. keep on doing this diy classes mate, they are very useful and well explained!
Hi, Thanks for this video. I made a vactrol gate based on your video using a 40106 integrated circuit as the LFOr. I have a Korg SQ-1 and wondered if you know anything about how i'd go about using it to make gate patterns in a similar way to how you have used the CV out from the 0-coast as an LFO. I assumed I'd be able to get the Gate from the SQ-1 output and achieve my desired result but it's seemingly more complicated than that.
Hi James. Normally an Envelope Generator goes first, between your sequencer's gate and the LED on the vactrol, but it should work with a gate directly connected too. You need to make sure the gate output in your SQ1 is set to POSITIVE. If it doesn't work check with a fresh LED and see if it lights up. If it does, then the problem may be the polarity of the LED inside your vactrol.
Great, thanks. I will try this. I had some results out of it but it wasn't as simple as a high gate lighting the led which was strange.
Nice :) If this is #2 though, where is #1? Can't see it in your uploads.
It's the one about making a midi cable for Arturia/Make Noise. I didn't name it #1, but it is :)
th-cam.com/video/-NFNbDSVX5I/w-d-xo.html
I have a vintage stereo that uses a few of these types of devices in the fm receiver signal section, mainly the multiplex board. Could a variable resistor be used to adjust for best performance.
09:04 BETHOVEN! :D
Hey! I'm pretty much a noob at this but I've seen people putting the resistor AFTER the LED part of the vactrol, at the "cathode" end (as I understand, with any diode there's a Anode, the recieving end, and a Cathode, the blocking end). I always thought putting the resistor on the anode end made more sense, that's where power comes from. Do you know of any reason why some would put a resistor at the cathode end? Thanks for this great tutorial, I'm going to put it into practise soon and hopefully force 4 LPG's in 4HP (I'll be using a protoboard at the back of the panel haha)
Little late, but it doesn't matter the order, it will reduce the same current anyhow
Hello and thanks for this. I love the sound of a LPG. I built this and it works great on my Pulsar 23 but I can't get it to work right with my Behringer MS-20 clone. I think the EG1 on an MS-20 is only 5V max so it doesn't drive the LED hard enough. Do you have any idea where I might look for info to get the vactrol values appropriate for the MS-20? TX.
Ha! Got it. I used all the component values you did but changed the resistor before the LED to 260R. Now, I got the thonk on the K-2, too.
hi, thanks for the video. did you messure the resistance of the foto resistor when the led is on? i had only a green led... out comes 50kohm for the light resistor. wondering if and in which direction i have to adjust the capacitor...
Hey! No, no measurements... but to find out what cap to use, it's easy. Put one in, listen to it, if it sounds too dark (filtered) use a smaller cap, if it sounds too open, use a bigger one! I found 100nf worked for me but yeah, that'll depend on your LDR too. You may also use a smaller resistor for the LED, looks like yours is lighting up kind of dark!
Best of luck!
hey thanks a lot for the reply. i could not wait for your answer and did exactly what you are suggesting. looks like the resistance of the ldr does not matter to much. have only a 2,2 nf and a 100 nf at hand. 2,2 nf to open. 100 nf little bit to "dark" but should do it. looks like the 10 nf might be the best choise for me too...i built 2 gates next to each other with the same components and sure enough the 2 vactrols are not responding equaly :-)
Whuuu! Scary music 😨😨😨
The light-dependent resistor, does it not wear out over time? Or is its lifespan good?
not at all, it will outlast you :)
@@QuincasMoreira cool
im just using the audio from two ic555 chips ...will I get the same seq sound? you mentioned the audio you have going in ...do you have a straight tone going in and your out put makes a sequenced sound?
Hi, the LPG is like a VCA. it only controls amplitude, so you can use an Envelope Generator to control the volume of the sound. It does not generate sequences, for that you need a sequencer
I'd like to try it with an industrial vactrol. Can someone give me advice about choosing between those on THONK?
They are VTL5C from XVIVE. Can't put the link here
really cool !
Is it a Passive Low Pass Gate or a just Passive Vactrol VCA ?
What can be done (simply) to adjust the low pass part ? will changing the value of the capacitor or put a pot in series or parallel to it change the band pass ?
well, it is a low pass gate, it would be a VCA if you remove the cap to ground. Changing the cap value will affect the cut off frequency (bigger= lower) . Have fun!
@@QuincasMoreira Thanks ! I'll try with different caps, can you give me an advice about the acceptable range of the caps to try ?
@@KNHSynths ANything between 10nf and 10uf!
@@QuincasMoreira Quite a wide range :-) Thanks for the information.
Fantastic video. I was wondering how to Implement the tone switch. Is it just adding a SPDT switch with a different resistant party or is it a Capacitor? Thanks
it´s the cap!
@@QuincasMoreira thanks man. Wicked video by the way!!
@@QuincasMoreira do you know what would happen if I put a potentiometer in place of the 33k - would that also change the tone?
@@subcityofficial9409 the resistor just controls the luminosity of the LED, it's more about response curve than tone
Would it be worth it to use a pot in place of the resistor for fine tuning?
I would also like to know this. Thanks.
I think that a pot by itself probably wont work, if you go above the LED voltage limit you'll fry it. Though i reckon you could use a pot and a resistor in series, that way the resistor can protect the LED from getting fried.
Two questions you can perhaps answer:
A) Why is it called a Low Pass Gate? I've never understood that really.
B) What are the functional differences between an LPG and VCA?
All my synth learnin has pretty much been east coast school. I'm trying to wrap my mind around west coast school, but just don't really understand some of the concepts. I can use them, mind you. I just don't really understand them, which makes it hard to design sounds deliberately rather than "discovering" them experimentally.
Hi. A low pass gate is basically a low pass filter used as a VCA. It's actually cutting the high frequencies rather than just amplitude, which gives it it's characteristic west coast sound. The capacitor to ground after the LDR makes it a one pole low pass RC passive filter. That is the functional difference, as a VCA only cuts amplitude. Feel free to ask other questions you may have about west coast synthesis, cheers!
There is no real norm here, but a LPG is typically a Lowpass filter combined with a VCA. So not only do attenuate a incoming signal (= make it more silent), but at the same time cut the high frequencies. If the LPG is fully open the signal is passed with all it's frequencies. If it is only half open the signal is attenuated and has high frequencies cut of. If the LPG is closed, there is nothing to be heard. In short: a LPG attenuates high frequencies of the Input faster than low frequencies.
A VCA on the other hand does just volume and does affect all volumes equally.
Additionally to that the LED/LDR combination (vactrol) used in a LPG is slow. That means if you send a short burst (e.g. a Trigger) to it, it does not immidiately switch off after the signal is gone but "rings out" a bit. google "Buchla Bongo" to hear what that sounds like.
bro thanks a lot can u adice a breadboard mine is very hard and breaks even precutted wires when i stck them in
Hi! I don't really know much about breadboard brands, sorry :)
I hardly ever use them these days, prefer to solder things up even for tests
if you send a gate signal in, will there be a slight decay curve like on other vactrol lpgs?
yes, that'll depend on the LDR response time
Synth Diy Guy do you have a preferred LDR for that function?
@@TechRedstone i like using high value ones, like 2M
Thanks for the video! So what does this do exactly? I honestly couldn't hear something. I came searching for a low pass filter to make a foot stompbox drum out of a piezo disc and cut all frequencies sharply above about 70hz out of the signal to the mixer. Is this what i need :)?
Thanks! No, this is a low pass gate, not a low pass filter! If you hear silence, that is the lopass gate at work, it's acting more like a volume control than a filter. Without it you would hear the synth constantly droning with no volume envelope at all.
To make a simple low cut filter at 70hz you need a capacitor and a resistor:www.electronics-tutorials.ws/filter/filter_2.html
@@QuincasMoreira Oh fantastic! Thanks!
By far the most superior vactrol video > thank you Bo$$. I'm using a 2.2v LED with the 0 coast contour, and it works great. Only thing is though there is no resistor needed, from the Contour output. If I use a 33k resistor it won't light at all, even a 1k it's dim. I thought contour would have a hotter output; after measuring it on a meter it came out around just under 3v. What's the voltage coming out of your contour output if you get chance to measure? Thanks again!
Hi! Thanks for your nice comment :)
The resistor is there to protect the LED from burning out due to excessive current. Not using one may be fine for the 0Coast, but beware of other EGs that may put out up to 10v. In fact my 0 Coast (just measured) puts out 7.5v, it seems very strange to me that yours is only outputting 3v... Do you have the sustain pot on Max? If so, I would try to get it fixed by MN under warranty. They are good guys, surely they will help you :)
Cheers!
Q
Thanks very much for the quick reply! The output is indeed very low on my contour. Thanks for checking the voltage for me. I'll check with MN and see what they say, they may have a ref. measurement I can take. I'll give it a quick factory reset first. They are great guys, very helpful!
I'm really pleased with the result from this gate. I'm making an EG to drive it, and that will output enough to fry the led! I will experiment with the output level of that EG, probably around 10v, probs need at least 40k.
that'll depend on your LED. A 10 K resistor is likely enough to protect the LED, more than that would be more about fine tuning the LED response.
Thank you for the insight!
Hi! But... that exactly LDR you are use? :)
Hi! I think these are 10M LDRs, 2M should work well too. To much lower and you won't get it to close up completely, I think.
...mmm....I might well make both and filter the APC with the Vactrols..if I control it with a s&h rather than the envelope I should obtain some interesting rhythmic sounds..do you think it would work?
that sounds like it would work and be very interesting!
What is the value you went with for the current limiting resistor?
I don't remember! Probably 1K :)
Different LEDs will work better with different resistors, so try a few, from 1k to 10k
So why would one need another non controllable VCA if you can already control the CV/gate before it goes thru this vactrol? Wouldn't you need a potentiometer on the LDR?
This is to affect audio, no pot needed, only CV from an EG or similar modulation source. VC= Voltage controlled, not non controllable ;)
@@QuincasMoreira Oohhhhhh so this vactrol idea is a way to introduce CV into something that doesn't have it. tyvm for this video dude!
@@QuincasMoreira wait, now this seems redundant. If you have a modulated source changing LED value, and LDR output changed value... why not just plug LED source into whatever and skip the vactrol?
Does he say the resistor value? I could swear he does but haven’t been able to find it. Thanks for any help!
Hi! The resistor value varies depending on the LED you use! more resistance for high luminosity LEDs, less for lower luminosity. You need to experiment!
@@QuincasMoreira thanks I was just nervous to experiment lol
@@mikesegarra869 don't be, it's the coolest part of Synth DIY!
yeahhh cool !!! but what do you say about powering this module? how to top up the bus board
It's passive, no power needed ;)
Quincas, I'm wondering, how's grounding managed in passive modules?? We use the jack gnd that cames through the cable?
@@alebrenna441 Yes.
What if you patch a 5 volts offset (from the math section) to audio in of the vactrol gate, audio output to dynamics and contour to cv input ? It should turn this into a real lowpass gate for typical buchla bongo
Amazing tutorial by the way :)
I don't quite follow the logic of patching DC into the audio input, but if I use the dynamics section of the 0 coast, that's already a lopass gate anyways ;)
It's to get a vactrol low pass gate. i thought you needed to have a dc offset though the circuit to open the dynamics like when you want a drone and then open/close it with the vactrol to get the smoothing effect. Anyway, I already ordered what i need to follow your tutorial :)
Edit : i just understood that the capacitor is here the lowpass filter :o
Would you be willing to explain how this can be transferred off the breadboard and onto a pcb into a module? Perhaps a dumb question since I’m very new to DIY
Hi Caleb! You can get a permanent breadboard, strip board or perfboard. Those allow the circuit to be soldered permanently rather than stuck on by friction. Do that and you'll have yourself an actual module you can stick into your modular :)
Synth Diy Guy thanks the the quick response! Thinking about making my own dual lpg
Caleb, watch my "deadbug buffer" video for an idea for the panel. And the LPG circuit can actually be soldered point to point, directly on the jacks, no need for even any kind of circuit board ;)
Hi does it matter what the capacitor is? What did you go for?
Yes, the capacitor influences the cutoff frequency of the filtering. I went with 10nf!
thanks!
I like your explanation and effort to show people ..but i would like to here the difference of the original sound ...and the vactrol filtered sound so you can hear what it really does..i heard lot of sounds but could not see wjst the folter really does..sorry for critic ..
Hi, the vactrol is basically a VCA here, so without it you would just hear a continuous sound, without the silences in between notes.
What is the best color LED to use for this?
Hi Grayson, Buchla used RED because that's all that was available back then. I use white myself but I don't think it makes much difference.
Synth Diy Guy Ok. I’m working on a mini pcb for a similar design.
What VST I could use as modulation source?
This is analog, real voltages, not digital information. VSTis will not work, unless you set up a MIDI to CV converter. Then any mod source will work
Please help, I am entirely new to this and I got some 3.5mm jacks to do this, but idk which legs are ground or signal. There’s 3 legs, is there a ground and pos/neg signal or is it just ground and two signal?
Hi Elyssa. Usually one leg is the signal, one is ground and one is the switch. It's a terminal that gets connected to the signal one only when no jack is inserted. It's used for normalization.
I don't know which jacks you got though, so you should find the part number and look up it's data sheet!
@@QuincasMoreira I think I accidentally got a TRS jack, will that work? Do I connect them together on the same column of the breadboard? I looked at the data sheet and it didn’t really help :P
@@elyssapalmer2298 TRS are for balanced or stereo connections. It'll work, just ignore the ring connection. Use tip and sleeve only. tip for signal and sleeve for ground
@@QuincasMoreira great, thank you so much! I could not figure out what I needed to search or how to figure this info out. Hopefully I’ll have more luck moving forward w this circuit. Your videos are super helpful btw!
@@elyssapalmer2298 the data sheet should say which terminals are tip, ring and sleeve, or you can use a multimeter in continuity mode and simply measure! Best of luck, cheers!
What if you wanted this in addition to a potentiometer?
What would you want the potentiometer to do?
Why the 33k resistor? I thought current limiting resistors for leds are usually under 1k.
that depends on your power source and how sensitive the LED is. It also affects the Lo pass gate response. I arrived at this value experimentally for my particular LED and LDR. Eurorack can put out up to 10v though, so yeah, less than 1k is definitely not enough. You may be thinking of digital circuits powered by 3.3v.
That was quick, Thanks! I was aware that the appropiate resistance is relative to the supply voltage, i just didn't really take in to account that the response curve has to sound good. Guess i'll have to use my ears. Probably not a bad idea anyway.
Synth Diy Guy, Add a 25K potentiometer between 10nF and the audio "path" : )
I've built a couple of these LPGs. What does the pot do - does it vary the filter characteristis of the capacitor?
@@mcshafty1 yes, RC filter.
@@mcshafty1 if you want you can calculate the cut off point. and have a real filter
1 / ( 2 x π x R x C)
where R = Ohm and C is farad. so you have to shift the value of the cap.
1 uF = 0.001 Farad.
1 nF = 0.000001 Farad.
nl.farnell.com/uf-nf-pf-capacitor-conversion-table
@@AnalogDude_ Thanks for the additional info @Analog Dude
Some posts on that forum thread are saying "that's not a low-pass gate it's just an attenuator" but... the LDR part of the circuit at th-cam.com/video/8BOnvSQpoGY/w-d-xo.html looks like a low-pass RC filter to me, is that right? Thanks for the video, it's really good!
yeah, as long as there's a cap to ground it's a filter. If you skip the cap and use just the LDR then it's more just a VC attenuator. Thanks!
This video is great to explain a vactrol but I guess I really didn’t hear the effect of the low pass gate as much as I was hoping to. Still love your channel though.
it's more like just an optical VCA. the classic Buchla sound requires a more complex active circuitry
I can not hear the difference with the filter and without so can not compair what the lpf really does..sorry
without it you would hear a constant tone. The LPG is a gate cutting off the sound to make rhythms
imo, voltage for synth, vactrol for fx...
tell that to Don Buchla ;)
Great informative video, however the reverb on the voice it makes it quite difficult to follow. For me, at least. It's like, I'm in a tight acoustics room and you speak to me from a cave. When it's music it's fine. But when it's speech you need to follow along, it gets quite distracting. Otherwise, great info, like I said.
something that controls your Vacuum🤣 ?