DIY twin t kick drum module for modular synth

[@constantine333B]

OK this is actually sick sounding, I have been looking at way more complicated kicks for DIY but I'm gonna go for this one!

[@constantine333B]

@LAURISDIYCHANNELTV can you share what kind of switch you used for the RC filter? It looks like it's just one double-pole or something, but I haven't been able to find such a thing online. I have been trying to think of a way to use one simple two way switch but I don't think it's possible. Maybe I'll just leave the RC filter always on. Should have breadboarded first XD

[@LAURISDIYCHANNELTV]

@constantine333B you can search ”DPDT 6 pin” on ebay, amazon or whatever and you should find these switches! I guess you could use a single switch so that it disconnects the capasitor from the circuit (So in between the 10k resistor and the 104 capasitor.) When disconnecting the capasitor, that would leave the 10K resistor in the signal path but i dont think thats going to make a huge differnece, it should just make the output a little bit more quiet

[@constantine333B]

Oooh good idea! Need to get my active mixer module together anyway so I can boost the signal there. Thanks man!

[@aaronstclair2423]

I built this on breadboard. I like it. I'm gonna build a strip board and put it in my rack. Thank you for this!

[@stefanhansen5882]

That bass sound is awesome!

[@klassisch9093]

Thanks a lot! Your videos are always so informational

[@shean4]

Thanks for your videos. Really have fun with these. I added a DC blocking cap to the twin diode clipping circuit (between the switch and the diodes), otherwise only one of the diodes turns on. I tested a few and 330u seemed good.

[@LAURISDIYCHANNELTV]

Oh shit I think I had like a 10uF cap there that I forgot from the schematic! I'll add it to the schema in the dropbox link if anyones wondering about this! Thanks for pointing that out!

[@Rob_65]

Nice sound. Thanks for combining this from all different resources. The origin of this circuit (as far as I can trace back) goes back to the January 1978 edition of the Practical Electronics magazine and it has been going around in similar form over the last 35 years. Your version works great there is just one error in the schematics: pin 8 and 9 of the 4069 are swapped (pin 9 is the input, 8 the output of the inverter) I made some small modifications to get it more to my liking: I changed the 104 capacitor on the input to 1 uF to get a better sound and I changed the 100 (10 pF ?) capacitor on the final gate to 10 nF. With the 10 pF capacitor the initial click on the drum was too loud for me.

[@LAURISDIYCHANNELTV]

Thanks! Oh yeah thanks for pointing out the error in the schematic, i always get these pins the wrong way in my schematics haha! And thanks for the improvement ideas, i’ll definitely try them out cause i’m building a similar drum to another project at some point!

[@Rob_65]

​@@LAURISDIYCHANNELTV I was even thinking of building one of these with one of those more expensive (60 cents or so) IC sockets with round pins to be able to experiment with different capacitors

[@LAURISDIYCHANNELTV]

@@Rob_65 oh that would actually be preatty cool!

[@Rob_65]

@@LAURISDIYCHANNELTV I was thinking of putting this on the PCB such that I can play with values but I was just thinking it is way cooler to have them on the front-panel. Would be a great commercial module: a drum with a bag of capacitors so users can play around to get the sound they like 😁

[@LAURISDIYCHANNELTV]

@@Rob_65 haha that would be awesome!

[@ekvalisaatorid]

Moi. Really cool stuff! You should make a jam video with your synths

[@LAURISDIYCHANNELTV]

@@ekvalisaatorid thanks! I was JUST thinking the same!!

[@nmidu]

yes man, big hug from argentnia

[@CircularMirror7]

Looks like a awesome drum 🥁 Gunna put this project on the list 👌

[@djkrztoff]

Has anyone done a stripboard layout for this?

[@shean4]

This kick drum circuit gives a nice range of effects. I've built 2 of these now based on your cct. One thing I've noticed is that the circuit seems to pick up any noise/signal that is on the power supply and amplifies it. If I unplug the output of the kick drum the effect goes away. Anyone else noticed this? I've tried adding some larger caps to the power supply rails on the kick drum cct board. This reduced the effect a little bit, but didn't eliminate it. Interested to know if other people also see this effect.

[@LAURISDIYCHANNELTV]

Nice to hear the circuit has been useful! 😊 I havent noticed any noise problems with mine, but i only have a couple of modules in the same case at the moment! I forgot to mention it it the video, but you should remember to connect the ground connection of the inputs and outputs if youre using regular minijacks or jacks! But of course i dont know your setup or if that would even matter! But if anyone else has noticed a similar problem and has a solution, please let us know!

[@Theaphextwin972]

With the cv or gate can you trigger the kick drum with trigger outputs on a drum machine like the behringer rd6 a clone of the 606

[@LAURISDIYCHANNELTV]

Yes i think it should work with an RD6 trigger output!

[@Theaphextwin972]

@@LAURISDIYCHANNELTV thank you:)

[@dami6459]

Hi. Thaks for video. please tell me where the button is connected!?

[@LAURISDIYCHANNELTV]

There is 5 Volts going through it to the trigger input of the circuit!

[@dami6459]

Thanks a lot :>

[@boenglover2593]

Thanks for the video, but I'm having a little trouble following the schematics on a breadboard. Could you make a video of you building this on a breadboard? Or if you could help out a little with the schematics that would be awesome! Thanks!

[@LAURISDIYCHANNELTV]

You can message me on instagram and i’ll try my best to help! Theres a link to my insta in the description. And if you dont use instagram, go ahead and ask me here in the comments! 😊

[@boenglover2593]

@@LAURISDIYCHANNELTV Well when I plug in my clock circuit to trigger it, I get an oscillation. But none of the potentiometers work to change the sound of the oscillation. I didn't use any switches yet. I just went with a static route for now.

[@LAURISDIYCHANNELTV]

If none of the pots do anything, could it be some sort of a grounding issue? If your clock source and the drum circuit dont share a ground, it might lead to some sort of humming! Does it make any noise when the clock is not connected? You can easily try if the circuit is working on its own by plugging +V of your breadboard to the trigger input

[@boenglover2593]

@@LAURISDIYCHANNELTV Both circuits share a ground. And on the drum circuit i have both pair of rails strung to each other (positive to positive and negative to negative). And it doesent make a noise when the clock is not connected nor when i plug +V to the trigger input. I think I did something seriously wrong.

[@LAURISDIYCHANNELTV]

Then i would check all the connections again and if everything seems to be right, i would check if the ic chip is broken or something!

[@webservice2912]

I built the trigger conditioner and the drum part of the circuit (did'nt build the drive part), and when i plug in to the clean out it doesn't pulse it just makes a continuous sound in my headphones, like a synthesizer or something. But the decay and pitch do work and they change the sound. help??

[@LAURISDIYCHANNELTV]

If the pots work and change the pitch of the sound, it sounds like the circuit is working, but for some reason the filter is resonating too much! The module does self oscillate with certain settings, at least when you exite it with a trigger. So maybe double check the decay pot is working correctly and not broken or something, because it is basically the resonanse of the filter circuit, that makes the drum sound

[@LAURISDIYCHANNELTV]

If the pots dont change the pitch but change the tone of the sound somehow, then it might be something else, for example grounding related! Make sure all the circuits you are using are connected to the same ground

[@webservice2912]

@@LAURISDIYCHANNELTV okk, thanx

[@kadenshoemaker6669]

How would i go about making a drum pad to hook up to one of my diy drum synths like this one so i could use it as a effects snare and how could i make it have a sensitivity feature

[@LAURISDIYCHANNELTV]

I haven’t built one, but i’ve always wanted to! I think www.youtube.com/@TheAudioPhool made a video about a drum pad for similar analog drums a while back but its been a while and i cant remember if you can adjust the sensitivity or not! And i think there are lots of different circuits using piezo disks and simple circuits to convert the piezos output to proper triggers. If i end up building a pad myself, i will for sure make a video about it!

[@kadenshoemaker6669]

@LAURISDIYCHANNELTV thanks man ik i comment here alot and im probably annoying you but your like the only KZbin who actually responds lol anyways if you wanna know what i plan on doing with it i plan on trying to recreate a synare 3 drum pad so i can play joy division music

[@LAURISDIYCHANNELTV]

No problem, i appreciate the commenting! 🥰 Synares are cool! I havent DIY’d anything synare related, but i think the circuits are not too complicated!

[@kadenshoemaker6669]

@@LAURISDIYCHANNELTV his video is good its just id like to make a more reliable and more sensitive drum pad as his isn't going to be strong enough to play while drumming and idk about how sensitive it is i would like to make a pad of rubber and stuff doesn't if it's a circle or not i want it to be pressure like a synare 3 as this specific synth is really nice id just like to set up a pressure sensitive pad that transmits a signal or voltage of varying voltage or strength depending on the amount of force jt was hit with

[@LAURISDIYCHANNELTV]

I get that! Hope you find a circuit for your project! Maybe google “diy modular synth piezo trigger pad” or something and try to find piezo based circuits

[@sixteenlevel]

Could this be triggered by the positive output of an audio signal?

[@LAURISDIYCHANNELTV]

I guess it would depend on what the audio is and how loud it is. But i think it should at least make some sounds with imperfect trigger input sources. Do you mean taking a ”trigger” track from a computers audio output or something like that?

[@sixteenlevel]

@@LAURISDIYCHANNELTV like a drum machine, or guitar… just some sort of audio source.

[@cwrigh13]

Another great video!

[@LAURISDIYCHANNELTV]

Thanks! 🥰

[@piero9738]

You deserve at least the subscribers of youtubers like Simon the magpie

[@isaachorgan]

if you end up making more drum modules, once youre done, you should make a drum machine with each of those circuits, and an analog sequencer bcus analog sequencers are cool

[@LAURISDIYCHANNELTV]

I’m planning on making more drum modules and i have already started to build a drum machine separate from the modular! And i also might build a standalone trigger sequencer in the near future, because it would be very useful with the modular as well! But i have no idea when these will be actually done, because my projects tend to take forever to finish haha

[@flywittzbeats4008]

That thing sounds so damn nice 🤣

[@sockgoop]

If i change some of the capacitor values in the oscillator for a higher pitch and add a small noise circuit, would i be able to make a sbare drum from this circuit?

[@LAURISDIYCHANNELTV]

For sure! I’ve used the circuit for snare sounds even with these cap values! But caps for a higher pitch would be smart for a snare circuit. You can find a simple percussive noise circuit for example on Kristian Blåsol’s (modular in a week) channel

[@frankjames264]

Why is there a .1uf cap in parallel with one of the .1uf caps in the twin -t circuit? Shouldn't they be the same?

[@LAURISDIYCHANNELTV]

I was messing around with the cap values on breadboard and this is what i ended up with, I liked the pitch range with these values! I’m sure it would be better to make both sides the same value, but i only had certain cap values at hand at the time and i was happy with the circuit like this

[@frankjames264]

@@LAURISDIYCHANNELTV Cool! I'll try it both ways and see what I like.

[@kellerdev2905]

Sounds great!

[@garywallace1938]

Do you know, if this will work with a 40106 chip?

[@LAURISDIYCHANNELTV]

It’s a different kind of an ic chip, so no! But it should work with a cd4049 hex inverter as well!

[@AlienFrog648]

I need some help, please. I've built the circuit and it sounded nice until it didn't. It starts to oscillate like crazy and eventualy the ic fries. I checked the circuit, it's all acording to the schematics. And why didn't you use coupling caps on outputs? Looking forward for the reply.

[@LAURISDIYCHANNELTV]

Hmmm not sure what could be causing that. Did you check that it wasn’t just a faulty ic chip? Are you powering it with 12V DC like mine or soething else? And what are you using as a trigger?

[@LAURISDIYCHANNELTV]

@@AlienFrog648 oh and i didnt use output caps because i didnt know what i was doing and still dont! Im not very knowledgeable when it comes to electronics but im learning as i build more and more stuff!

[@AlienFrog648]

@@LAURISDIYCHANNELTV Thanks for the reply! It might have been faulty ic since I bought the cheapest ones from local parts store, tried with 2 chips, both failed. I'm powering the circuit with a 12 volt adapter, beatstep pro as a trigger. I'l try this chips in more conventional applications and check for instabilities.

[@LAURISDIYCHANNELTV]

@@AlienFrog648 okay, thats all i can think of at the moment! I was thinking something like this could happen if the chip somehow got a negative voltage to its inputs, but it doesnt really sound like thats the case with your setup. I fried a couple of 4069s like that when i was building a filter. Just like yours, it worked for a little while and sounded fine, but then started acting up and the chip fried

[@AlienFrog648]

@@LAURISDIYCHANNELTV Thanks, Lauri! I figured it out, those were just bad ic chips, they are quite unstable. I replaced them with some made by Texas Instruments and it works like a charm! Many other twin-t drums sound kinda dry to my ears, this one sounds a lot better, IMHO. Thank you greatly for your circuit and help!! Much appreciated!

[@flywittzbeats4008]

Thanks a lot Lauri, now it looks like a robot had diarrhea all over my studio space because I now have an electronics problem. Nice vids though (;❤

[@LAURISDIYCHANNELTV]

Hahah i’m sorry! 🙃

[@JUSTaCringeChannel]

Awesome!

[@PandaKattPk]

Amazing video

[@zhou_sei]

dude wow

[@Entropy-Machine]

Thanks for this, glad to find you. Subbed!

[@LAURISDIYCHANNELTV]

Thanks for watching and subbing! 🙏

[@sunshin3man]

hi and thanks for sharing. a silly question - pitch potentiometer shoud be stereo , correct?

[@LAURISDIYCHANNELTV]

Yes its a dual gang potentiometer aka a stereo pot!

[@DCPier]

Hi Lauri, it's me again with another stupid (?) question: The 0.22uF cap near the stereo pot, does it really have to be a 220nF electrolytic cap? The E.W. original circuit shows the non polarized cap symbol (foil/ceramic?) which seems quite logic to me because 220nF is a quite unusual value for an electolytic one (they do exist though).

[@LAURISDIYCHANNELTV]

@@DCPier yeah i think a non polarized cap should be totally fine! I just drew the schematic with the exact component i used myself and i happened to only have 220nf electrolytic caps at the time

[@CausticCatastrophe]

cool stuff!

[@floorganik]

Really nice drum module ! Is it possible to trigger it using an electronic drum kick like the Roland KD-8 kick pad ?

[@LAURISDIYCHANNELTV]

I've sometimes used the module with a simple amplified piezo drum pad, but the output isn't the same as with a 5V trigger. It does make a sound, but the sound is kinda softer and more responsive to the input signal. I'm not familiar with the KD-8, but if it's a passive piezo pedal, it would work in a similar way, but you would also have to amplify the signal before plugging it into the module

[@floorganik]

@@LAURISDIYCHANNELTV Hi Lauri, thanks a lot for your answer ! Do you have a 5V amplifier circuit to recommend ?

[@LAURISDIYCHANNELTV]

You might be able to use the overdrive part of the modules schematic as a passable amp circuit! You can also check Doepfers DIY page on their website for some simple diy circuits, i remember them having a simple op amp amplifier circuit and i bet it could be powered with 5V and ground instead of the eurorack +12V and -12V

[@LAURISDIYCHANNELTV]

You can find the website by googling ”doepfer diy”

[@OlegStepp]

Cool module. Why is the sound very low? did I assemble it incorrectly or do I need to connect to an amplifier?

[@LAURISDIYCHANNELTV]

Thanks! I just realised i forgot to make a small correction to the schematic! The pins 8 & 9 of the cd4069 were marked the wrong way around! So if the overdrive output is quiet, that might be the reason, sorry for that! I updated the dropbox link in the description and everything should be working now. If that wasn’t the problem, then i dont know what it could be. For me the circuit is loud enough to use with my modular synth! So then maybe check if theres any errors or broken components in your circuit. Hope this helps and hope you get it working properly! 😊

[@Novemtails]

We want more videos of you, pleaseeee

[@LAURISDIYCHANNELTV]

I’m working on a bunch! 😊

[@Novemtails]

@@LAURISDIYCHANNELTV great!

[@volanoisystuff2879]

Hyvä meno taas!

[@LAURISDIYCHANNELTV]

Kiitoksia ja kumarruksia taas!

[@draconianrhythms]

What are the boards you are using here? They look really useful

[@LAURISDIYCHANNELTV]

It’s a prototyping pcb i desinged and order from jlcpcb! It’s like a breadboard, meaning theres always a row of 6 soldering points connected to each other. This makes prototyping simpler and i have to use way less wires to connect components! Heres a link to the gerber files, if you want to order some yourself: www.dropbox.com/sh/yw0j4umez1evwmp/AABw4nE_mRQAVi5pAXoBGCRpa?dl=0

[@LAURISDIYCHANNELTV]

You just need to upload the gerber zip on a PCB manufacturers website like JLCPCB or PCBway for example!

[@draconianrhythms]

@@LAURISDIYCHANNELTV dude, thank you so much. I did have some ideas similar to this, but never found the time to learn kicad. I will use your design, with great thanks and appreciation. Nice one ❤️

[@sergioavia]

Greetings. I follow your channel with interest. In this video, in addition to the review on the main topic (Kick), I was very interested in one module, namely the CEM-SSM filter. Is it possible to make a separate review on it, or at least give more information about this device. I will be very grateful.

[@LAURISDIYCHANNELTV]

Hey thanks! I haven’t been planning on doing a video about the filter, because i built it a long time ago, but i will think about making one now! But it is basically just the high pass schematic from the cem3320 datasheet and the low pass schematic of the ssm2044 datasheet built to the same module and normaled together. I love a high pass before a low pass, just like in the ms20! You can find great information on both filter chips on electricdruid.net! Thanks for the idea, ill think about making a short video about the filter ✌️👏

[@LAURISDIYCHANNELTV]

Heres the electric druid article on the ssm electricdruid.net/ssm2044-lp-filter-designs/

[@LAURISDIYCHANNELTV]

And the one on cem electricdruid.net/cem3320-filter-designs/

[@sergioavia]

@@LAURISDIYCHANNELTV Yes, I am familiar with these materials. Did you use original cem3320 and ssm2044 or AS3320 and something else? The original ssm2044 is quite hard to find now... Well, I really liked the sound of your filter, just like the "early MS10". Looking forward to the video and review of this wonderful device))

[@sergioavia]

@@LAURISDIYCHANNELTV I have about 8 pieces of serviceable cem3328, I got it from a disassembled Ensoniq SDP-1 piano ... I'm thinking of using them in some kind of filter too ...

[@doohmritual]

Hello!! Great video!! One question, I want to make a version with the 40106 as clock, and I was wondering if it is possible to add an extra output to that clock pulse to synchronize other modules. Would it be as simple as adding a buffer to that clock output on the 40106 and taking the extra output from there with a 104 capacitor? Or is it not as simple as that? thanks :D

[@LAURISDIYCHANNELTV]

Thanks! Multiplying the clock signal should be very simple! I think a buffered mult would be ideal, but you could probably even just multiply the signal passively. So just wire the same clock signal to the drum and an output jack! I dont know if it doesnt work like that in certain setups, but with my modular i send the same clock to different modules by just stacking banana cables to the same output haha

[@doohmritual]

@@LAURISDIYCHANNELTV Thanks a lot! It's true, it works! :P Thank you! I have a question about the Trigger, I am building the circuit for 12v, but for the trigger button to send 5v should I take it from a 7805 regulator? Oh! And happy new year from Panama!! Thanks for your channel!

[@LAURISDIYCHANNELTV]

@@doohmritual Yes thats what i did, just a 7805 and a momentary switch! I think the trigger can also be 12V, but i wanted it to be the same voltage as other trigger sources in the modular. So im guessing if you use 12V its just gonna be a bit louder

[@maxwarfield6699]

I’m a NOOB to electronics. So, here’s my question: for the diodes clipping, don’t you need resistors, to protect the diodes, like 470 Ohms or 1K Ohm? Please, let me know, I want to learn. Thank you kindly

[@LAURISDIYCHANNELTV]

I’m really not that smart with electronics myself! I dont know if a resistor would be good practice to use with the LEDs but at least with this circuit theres no problem without. But if you’re using LEDs as power indicator lights or something else, then you need a resistor or the led will burn!

[@maxwarfield6699]

@@LAURISDIYCHANNELTV Perhaps, at that point in the circuit, the current isn’t high enough, to damage the LEDs? I should take some measurements… Anyhoo, thanks for replying. I truly am trying to learn more about electronics and your videos make learning about this stuff fun - you are one mellow fellow. Cheers mate

[@LAURISDIYCHANNELTV]

Yeah that might be the case! Thanks dude!

[@floretion]

According to the CD4069 datasheet, it can only deliver ca. 10mA of current at 12V supply. The maximum current for an LED is around 50mA (20mA is generally already extremely bright).

[@LAURISDIYCHANNELTV]

@@floretion Oh yeah that makes sense, thanks for clearing that out for us!

[@JackNiles]

Thanks man thanks bro thanks for the info I hope you have had fun and hope everything is well thanks bro hope your having fun thanks bro thanks man thanks bro thanks again

[@g-makeworld3123]

Hi! My name is Grigory. I'm interested in watching your videos. Do you have a scheme for a snare drum? I would be very grateful for your help!

[@LAURISDIYCHANNELTV]

I havent built a snare circuit yet, but im currently working on some analog drum stuff, and as soon as i manage to build a snare, i will definitely make a video about it! 🙂

[@g-makeworld3123]

@@LAURISDIYCHANNELTV Thank you very much! I'll be waiting!

[@g-makeworld3123]

@@LAURISDIYCHANNELTV kzbin.info/www/bejne/oJDGiIeorbBnZ5o

[@LAURISDIYCHANNELTV]

Oh yeah ive watched this and its awesome! Im planning on a drum machine based on the 4000 series CMOS chips that has kinda similar circuits and something different as well!

[@LAURISDIYCHANNELTV]

For some reason i cant see your message here anymore, dont know why! But if anyone else is reading this, it was a link to look mum no computers twin t drum machine video, thats a great video for anyone interested in analog drums, so here: kzbin.info/www/bejne/oJDGiIeorbBnZ5o

[@kellerdev2905]

Hey, sounds great and very simple design! I am wondering though, isn't the output going to be only on the positive part swinging between 0 and 12 volts?

[@LAURISDIYCHANNELTV]

Thanks! Yes the output is between ground and 12V, but i see no problem with that! A lot of audio sources are unipolar, i think for example my cem3340 oscillators are as well. And of course digital arduino modules etc

[@kellerdev2905]

@@LAURISDIYCHANNELTV Thanks for the response. I consider trying to build this module, and I thought I would put an RC passive high pass filter on the output, to get rid of the offset, but as I understand even that is not necessary right?

[@LAURISDIYCHANNELTV]

Yeah this has been working perfectly fine for me, so no need to add anything to the output!

[@MrDudumassa]

Amazing, how i would love.to.know

[@Mp3acid]

Noice

[@azador2677]

ily

[@micyclebicycle]

look mum no magpie!

[@LAURISDIYCHANNELTV]

😂

[@wvo2m]

Ooooo! 🤡