this is a project based largely on the put up or shut up mentality, for quite some time I've been getting annoyed at seeing youtube videos of people pissing about with these "synths" which are basically boxes of 555 timers with a million knobs that make stupid noises that you couldn't ever actually use in music so I thought I would make my own little synth that would get repeatable sounds and be useful in music and what better type of synth? a droner type - basically cause I love bagpipes - I like drones
anyway the circuit itself is quite a simple one basically because I only designed it during the week, all it is really is 3 triangle wave generators configured to operate in the audio range going into a mixer op-amp configuration with the odd filter here and there to soften the waveforms
I've used LM358 op-amps cause they are the cheapest, I'm not too sure if others would work in the same way though they probably will.
why call it the devils triangle - well it has 3 oscillators one of which can oscillate a slightly high pitch range (for melody) it also sounds demonic so the name fit
Hope you enjoy
EDIT: I replaced the level knobs with on/off switches - it makes it so much more versatile being able to silent certain drones
EDIT: I added a little schematic on how the switches should be wired as it was causing a bit of confusion.
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| the one I made - with a really shit paint job |
Thank you for posting this, I built it last night and it is a fun circuit that worked right away.
ReplyDeleteI am having a problem with the sound of the oscillators still being in the signal at very low volume when they are in the off position. Is the circuit designed to do this?
yeah it does do that which is why I changed the level knobs for on/off switches, it ended up being much better for it. I suggest you do that
DeleteYeah, I built it with SPDT switches rather than volume pots, maybe I there is a bridge or problem with my building!
ReplyDeleteaye it could be a little whisker of solder across one of the traces - it happens to be an awful lot so try running a nice sharp blade down the in-between parts of the stripboard.
Deletetechnically other than grounds and V+ the signal should completely isolated from the output stage of the circuit.
on another note Please post a picture of it when you're done - I'd love to include it on my "other peoples builds" page
Hi.
ReplyDeleteWhy are you using leg 7 for output?
I have built some drones by my own before but I don't follow your idea.
Hi Paul
ReplyDeleteLoving this drone machine reminds me of a fave from the past "Michael Brooks Hybrid LP" - really wonderful! Would like to know what value as well as log / linear potentiometers you used for the build - also a little confused as to where to wire the three toggle switches... is it simply a case of a wire to an on/off switch to the channels? then all to the output socket? also what to do at 20d (CH1,2,3) Level 2
many thanks - cant wait to build this
Hi Paul, i had build it with a few mod
ReplyDeletehttp://www.youtube.com/watch?v=AXjA_ZYYIkM
i had a strange problem with the mixer: with just one stage, everything fine...with 2 or 3 stages...no sound. My solution was replace the 100K resistor on the mixer lm358 with a 100k trimmer for gradually lower the value and have sound.
Nice project...a little monster...
that is really cool - I'm glad someone other than me built it and actually built on it too
DeleteHi.Great layout as always. Maybe i'm being stupid but what value pots are recommended for this project?
ReplyDeleteThanks, Matt
there is a schematic with them on!
DeleteHi. Love the idea behind this and it sounds great too. I've started making one and got all the components fitted onto the perfboard but I'm a bit unsure as to how the offboard components are mounted. I'm guessing the pitch 1,2 and 3 connections are for ground(1), wiper(2), and voltage(3) respectively. Is this right? Also I'm not sure where to wire the connections for the battery and jack output. Any help would be great.
ReplyDeleteHey Paul,
ReplyDeleteIm fairly new at this. A friend asked me to build him one of these, so I got the parts and assumed I'd make one for myself as well. Neither of them are currently working. I accidently got On-Off-On switches, but just used the middle pin for 2 and 1 for 1 just as in the wiring diagram. Could these switches be why no sound comes out? I have built a few pedals, and I am decent with soldering. Although I am not ruling that out, I wanted to see if this could be the problem from somebody with experience.
I doubt that's the problem - I often do the same thing through laziness.
Deletewhat I would suggest is leave it for a day and then come back to it and check component placement, jumper placement and cut placement - these are areas I often mess up on when I do mess up. the other thing I routinely do is run a blade in between each track to make sure there are no solder whiskers bridging the gaps - there have been so many times that has been the issue with a non working build.
I already did the blade check, and double checked for continuity with a multimeter. I will give it all a look over again to double check placements. Thanks!
Deletehonestly - I know it seems like "non-help" when I say check placements and stuff. but the amount of times I've been over something 8 times finding nothing wrong - leaving it a day and then checking again and finding something is uncountable!
Deletealso, you have used the op-amps that are listed because you can't put anything in there = they have to be single supply op-amps
I have STMicroelectronics LM358Ns in them. This is the exact one that I ordered:
Deletehttp://www.taydaelectronics.com/lm358n-lm358-358-low-power-dual-op-amp-ic.html
Is that not correct? Thanks so much for your time and help! Once I get these running, I will send you some pictures of them.
few questions... where does the input go? with the pitch pots- would "(1) pitch 2" be lug 2 of the pitch 1 pot? and "(2) pitch 1" be lug 1 of the second pitch pot? also with the output... would you just take that to lug 1 of a pot and lug 2 to the output?
ReplyDeletei see 100k listed as the pot value of the pitch pots- linear work best I assume? and maybe a 100k log for the master volume?
Thanks a bunch! cant wait to build this awesome sounding circuit!
"1) pitch 2" be lug 2 of the pitch 1 pot? and "(2) pitch 1" be lug 1 of the second pitch pot" - yes that's right.
ReplyDeleteI use linear pots yes, but you could experiment having 1 pitch knob as a log one and see what happens - it won't change the pitch range but it will control alot differently.
you can use a log one for the master volume but again, I just used a linear one
did you build this using the layout posted here? just wondering if this particular layout has been verified? cant wait to build this and more of your awesome projects!
ReplyDeleteyes - the process with all the layouts on this site is that I design a circuit, I lay the circuit out on stripboard and then I build the stripboard - if it works it gets put on here if it doesn't work I swear for an hour haha
Deletebut yes all the layouts on this site have been built by me and they work
im interested in trying out the pots for individual pitch volume controls as I'd like to be able to match the perceived loudness of the higher pitches with the lower register settings. I was thinking id replace the 3 100k resistors with variable potentiometers, but the schematic looks like i'd connect them similar to the way the switches are connected... IE: lug 1 to the vero and then tie all the lug 2's together and to the one point above the output on the vero. Any suggestions?
ReplyDeletedon't take out the 100K resistors. they are part of the mixer/amplifier in the circuit.
Deleteyou could just try putting the pots in line with the switches
what do you think? put volume pots as variable resistors in front of each switch? like vero to lug 1 of each pot then lug 2 to each respective switches lug 1?
Deleteif i didnt want the switches could i just wire the volume pots like the switches are wired? vero to lug 1 of each respective pot then lug 2's all connected and back to board?
ReplyDeletevero tp lug 3, lug 2s all back to board and all lug 1's to ground
ReplyDeleteSo, got all the parts together, and tonight I'm gonna build this synth. When I'm done, I'll post some pictures of the progress.
ReplyDeletecool cool - if you do I'll post them in the pictures section. remember do it slowly
DeleteHi, Do I need LM358n or p?
ReplyDeleteGreets, Corvi
Before I switch all my switches to pots I was wondering why exactly were they ineffective in this circuit? was it because there was little adjustment range with the pot values you used? or maybe something like sound leakage with volume knobs down?
ReplyDeletethe reason I am so interested is because I'd like to be able to bring up the volume of the quieter low pitched tones when mixing with higher pitched tones which are perceived as quite a bit louder than the low pitch tones. I wanna do switches and pots... but if the pots arent effective because of something inherent in the circuit It'd be nice to know before I spend all that time.
Thanks so much- this thing sounds so cool
they were ineffective because I didn't ground lug 3 on all the pots but then I figured "bugger it, I want switches" so I just did that. I also needed room to add the LFO module I'm planning on making in the future at somepoint
Deletei'm trying to figure out how to wire pots with the switches... is that something youve already drawn up? i already got dpdt's with the extra pole for LED's
DeleteHi Paul,
ReplyDeleteI've built this and also the Devils Drone Sequencer, I have to say this synth sounds way better!
My only issue in this project is I've a lot of interferences and background noises, especially when the osc switches are in OFF position; the noise increases when I pass my hand over "CH level" cables.
I've had to use SPDT on-on switches and connect the osc output to ground when not routed to the op-amp mixer to avoid these noises, although some backgrounds still remains.
The headphone jack is connected to OUT and GND, and I'm using a 9V AC power adapter.
Do you have any suggestions?
Thanks.
you need to use a DC adapter - I'm surprised the AC adapter hasn't burned it out!
DeleteOps! I'm sorry, wrong translation... I mispelled DC with AC !
DeleteYes, I'm using a 9V DC adapter!
You might put a couple of pictures of the process, would help enough for many of us complicate to assemble, thanks
ReplyDeleteThis might sound dumb, but do i insert components on the back side of veroboard so that their legs protrude to the copper side? And what is the orientation of IC's?
ReplyDeleteyes that's right.
Deletethe orientation is shown by a little grey circle next to the first pin - in this case all the ICs are facing up
So, all facing up on the plastic side of the board, right ? First i make those "holes", red signs are where there should be no copper, then i insert components, then rotate and solder?
Deletehere is my friends site - he does a good step by step guide on how to use veroboard with pictures - it might be easier than me
Deletetrying to explain it http://www.sabrotone.com/?page_id=386
Thanks, that explained a lot, i actually knew that i need to mirror something just could not get what! :)
ReplyDeleteHi, are there any other ICs i could use instead of the 358? Would something like the LM741 work? I want to build this in the next day or 2 as a holiday gift, so I don't have time to order the 358 chips. Anything sold at radioshack perhaps?
ReplyDeleteOr perhaps a TL072? I've got tons of those.
Deletethe TL072 should be fine - not the LM741 - that is a single op-amp
Deletehowever radioshack should sell LM358s - they are extremely common.
Great, thanks! I'll try TL072. Radioshack does not seem to sell the 358. With the search function, I can pull up other ICs, but no the 358. I'll post back when if and when I get this thing up and running. Thanks for the project!
ReplyDeleteThanks! Slapped this together in a jam, using mostly Radio Shack parts. TL072 works great. Made for a relative for the holidays. Added an internal/external speaker switch, and a master volume.
ReplyDeletehttps://lh4.googleusercontent.com/-JEz1mOJGHdg/VJoVgt_r4tI/AAAAAAAAAy0/sbtkb4mDfBg/s800/IMG_0322.JPG
https://lh6.googleusercontent.com/-5t0ggS_z0H4/VJoVgqLh6PI/AAAAAAAAAy4/EABO4n82PZY/s800/IMG_0323.JPG
cool - do you have a picture of the insides aswell?
DeleteHey sorry, I forgot to take a gut pic before I handed it off.
DeleteIs there a way I could add 3 more voices to this circuit? Perhaps a daughter board of some kind? Would be awesome to have 6 voices!
I plan on combining this with some delay, tremolo, fuzz, and some filters in a box.
if you're feeling confident, I did a post that separated all the building blocks of this project so people could make as many drones as they wanted
Deletehttp://www.paulinthelab.com/2014/03/drone-synth-fragments-stripboard-layouts.html
Hi
ReplyDeleteI have built this on a breadboard using your schematic so I can experiment a bit before building it. Right now it's not making any sound. I'm wondering if I have the power done incorrectly. I have checked all the other components layout quite a few times now. What does the filled in arrow refer to? I have wired up a 9v battery as in the schematic. Is that the right type of battery to use? In the battery section of the schematic, is the filled in arrow the point where all the other filled in arrows connect to (hope that makes sense :) Cheers
yes, all the black arrows connect to each other. as long as the battery is full it should be fine.
ReplyDeleteit's hard to know what to suggest without the misbehaving circuit in front of me - the only thing I can really suggest is check everything again very slowly and also check voltages with a multimeter. make sure the 9v rail (all the pin 8s on the op-amps) is 9 volts and make sure the black arrows are around 4.5 volts.
Ok cheers. just checked my breadboard and it was a bit broken and somehow losing 3v. Then when i was moving it to a new board I realised one of the chip legs was folded under. I have sound now! thanks for your help.
Deleteno worries - that kind of thing happens all the time with breadboards. they can be a bit of a pain in the arse
DeleteHi,
ReplyDeleteI just finished my Devil drone. It sound very well, thanks Paul !
I made 2 versions, one like the orginal, and a other with a Lowpass/Highpass filter (MS-20 style).
Here a picture :
http://zupimages.net/viewer.php?id=15/20/wp35.jpg
One question, how I can have a more high and low freq with the VCOs ?
Hi!
ReplyDeleteFirst, thanks for sharing this project, I really love the tone of it. Next a couple of questions:
1. Is there an easy way to hook an lfo up to the lm358's through CV or some such to control qualities like pitch or timbre? If not, is there a complicated way?
2. What components are affecting the sound most? Like which resistors could I swap or replace/combine with pots or vactrols? How would I go about to make the bass deeper?
This comment has been removed by the author.
ReplyDeleteThis comment has been removed by a blog administrator.
ReplyDeleteBuilt this for fun yesterday (pretty much my second recent circuit build; took longer than I anticipated to get everything assembled).
ReplyDeleteWorks great but for a couple of idiosyncrasies. Not sure if this is expected behaviour; will troubleshoot it and look over the build carefully when I have some time, but wanted to ask about a couple.
1. Second drone (the middle LM358 and controls) kills sound output from everything when its pitch pot is lowered too far. Is this normal behaviour for the circuit? Seems strange given that drones 1 and 2 are nominally identical.
2. All the drones cover a fairly similar pitch range but one of them reaches a few halftones higher. Is this also expected or is the high drone supposed to be like an octave+ above the others?
n'ermind, #1 was due to connecting the second pot incorrectly. Works as expected.
DeleteFor a pure triangle output omit the diodes. With the help of an electrical engineering buddy we figured out that the diodes get reverse biased when the oscillator output hits a certain level (below the feedback circuit of the output amp) and the waveform levels out giving a truncated / saturated look at one peak of the triangle wave - like a semi triangle / semi square wave.
ReplyDeleteI mean, sounds good either way, but the output as shown is not a purely triangle waveform (with only one oscillator turned on).
DeleteHey Paul, great synth, I've put one together and have been trying to add an LFO control for volume modulation. I build this LFO,
ReplyDeletehttp://www.casperelectronics.com/images/finishedpieces/speak-n-spell/Speak-n-Xbending/LFO%20schematic2.jpg
But have been struggling to hook them up. I can wire the LFO output (labelled C on the circuit) to where the Oscillators go into the Buffer. That seems to work fine for my single oscillator version, but with three oscillators the LFO only seems to kick in at very specific volume/LFO depth combinations -- you mentioned you had plans of adding an LFO, could you perhaps shed any light on my situation or offer another LFO circuit that would work better? Cheers.
Has anyone built one of these using ribbon potentiometers? I think that would be insanely fun.
ReplyDeleteCranked one out over the last few days. Was able to squeeze it into a 1590 case! Endless fun with reverb and distortion. Thanks!
ReplyDeleteSry for that noob question, where's the Volume Pot?
ReplyDeletethere isn't one
DeleteHmm..and what's the gray pot, with the black dot above the LED? i would like to attach an master volume pot, but i don't know how, sorry for my rusty english, and lack of electronic skills.
DeleteHi. I've been trying to build this. Noob question -- I've got it all soldered up, but I'm getting no output. This is my first attempt at a project like this, so I'm guessing something has gone wrong somewhere. Any hints for debugging? Are there specific places I should be testing for voltage/signal?
ReplyDeleteThanks!
Is the output going together with battery minus or the artificial ground build by the two 10k resistors?
ReplyDeleteno, the out is going to your amplifier/speaker etc. GND goes to battery negative
DeleteMaster Volume pot wiring would be: Output of circuit to lug 3 of a 100kA pot, lug 2 to output jack, lug 1 to ground ?
ReplyDeleteThanks.
Would you be able to post some internal shots? I know i have this a little messed up because I'm not getting any sound. And i wanna see what it should look like. I'll post pictures when i get home but. To describe what i don't know what to do.
ReplyDeleteIs it OK if i don't use a 9v battery and instead use a power supply like you could a guitar pedal? And how do i wire the output up? I want to use a standard mono jack that you can use with a guitar cable and only one write connected to it doesn't seem right to me but i might be wrong. Any help would be very appreciated
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ReplyDeleteHi there! Is there any way to add the cv output, to use it with sequencer?
ReplyDeleteI also interested in this issue
DeleteI've done two of these now and the same each time :- I get one single tone rather than three. The pitch pots still have an effect but the third one hardly does anything and there is also a very slow note modulation of up to an octave that sometimes creeps in. I've triple checked all the components and put a knife in between all the tracks, etc . All the voltages suggested seem to check out. Any help much appreciated.
ReplyDeleteHave you done a sanity check on the outputs of each of the three oscillators? They should all be triangle waves.
DeleteHi Paul, I've created a new stripboard layout as I wanted the pots on the board itself. I've built one oscillator and the mixer thus far. Getting a nice triangle wave from the oscillator, but am getting this from the mixer: https://imgur.com/whXAveT
ReplyDeleteIs this what you expect? It sounds okay.
Hi Paul.
ReplyDeleteFirst off, thanks for the awesome project.
I have everything working, but I'm having a very frustrating crackle type sound when 2 or more oscillators are turned on. It is also not a constant sound, but shows up what seems like at the peaks and valleys of the waveform (though I don't have an oscilloscope to actually check).
I can hear it very very slightly (maybe) when one oscillator is turned on, but like I mentioned it is very apparent when 2 or 3 of them are on.
Any suggestions of which components could be the culprit?
Thanks so much for the help!
Hi Paul. Thanks for this synth, I like so much this kind of sounds.
ReplyDelete(and sorry for my bad english).
I made this project. Switch 2 and 3 is ok (I have sound, and potentiometers 2 and 3 can modulate it). But when switch 1 is on, no sound, even if I modulate with potentiometer 1.
When switches 2 and 3 are on, I have sound of 2 oscillators and I can modulate.
But when all switches are on (1, 2 and 3), there is no sound (only if I modulate potentiometer 2 and 3 high, when I modulate potentiometer 1 high, I don't know how to describe the sound, as if the sound has "no energy" and then it's silent). I double-checked all part of the circuits...
Hi Paul, thank you for this project.
ReplyDeleteI used your oscillator layout design from this project to develop my drone module in eurorack 4HP size. It sounds great even with only two oscillators. I've ordered some pcb's at pcb factory, and then have some spare. Two questions - how to credit your design on my modules when I would like to show them on my instagram, solder them for my friends, and maybe finally sell some of them on etsy? And finally - I would be very proud if you will add my project to your page at "things that others built" as this is my first smd pcboard drawn by me and soldered with my soldering iron in my life :-)
Best regards,
Peter
what would happen if i changed r9 and r14 to 100k ? thanks ! i built this into a little suitcase with some lfo's , a ring mod , a delay , filter etc . so much fun ! i notice one of the osc on mine the picth is higher and also it is lopuder . i am hoping to balance the volumes of all three osc , this is what the first question relates to . thank you . is one of the pitchs supposed to be higher and louder ? thanks .
ReplyDeletehello people from beyond the other side of reality. out here we are stoned...ejaculate
ReplyDeleteHi Paul, Thank you for this design. It is exactly what I wanted to build for my project.
ReplyDeleteI have put it together and I am having an issue with one of the 3 drones. The second one. The output is in a higher range (in pitch) compared to the other 2.
Do you know what might be causing this?
My soldering skills are not great so I am quite sure there might be something wrong there. I have run the blade along the lines and I can't see anything that's making contact at the moment.
Thank you again.
Hi! Thanks a lot for sharing this, is it possible to have a picture of the pcb build to understand how the pota are connected? Thank you :)
ReplyDelete