Modular Drum Machine

granoj · Joined: Jan 31, 2012 Posts: 4 Location: Finland

seriously I always thought Lunettas where all about bleeps and buzzzz but this has certainly changed my way of thinking. If this was released on 12" I would play it, crazy stuff Shocked

Psyingo · Joined: Jun 11, 2009 Posts: 242 Location: Canada

efabric · Joined: Jan 05, 2012 Posts: 19 Location: Caen, France

Great work, and great sound !

I just wanted to ask for a little bit more informations about this :

Uncle Krunkus · Posted: Tue May 15, 2012 5:38 am Post subject:

What chip is used for the swing generator? Schems?

Psyingo · Joined: Jun 11, 2009 Posts: 242 Location: Canada

JL · Joined: Jun 25, 2012 Posts: 10 Location: New England

I know it's been almost a year since the last post on this thread, but I was wondering if the schematics were still available for this. The sound samples are amazing, and I'd really love to build something like this for myself. Thanks!

L´Andratté · Posted: Sat Mar 09, 2013 3:05 am Post subject:

Sound samples -> 404 for me Evil or Very Mad

Psyingo · Joined: Jun 11, 2009 Posts: 242 Location: Canada

Psyingo · Joined: Jun 11, 2009 Posts: 242 Location: Canada

JL · Joined: Jun 25, 2012 Posts: 10 Location: New England

This is amazing! Thank you very much!

Psyingo · Joined: Jun 11, 2009 Posts: 242 Location: Canada

trav · Posted: Wed Mar 27, 2013 1:32 pm Post subject:

Thanks for fixing your links, Psyingo. Good to hear/see this great machine.

analog_backlash · Posted: Thu Apr 18, 2013 3:31 pm Post subject:

Hi Psyingo.

From your 4011 PCB thread:

Psyingo · Joined: Jun 11, 2009 Posts: 242 Location: Canada

Hey, sorry for the belated reply.

one chip that i've found to work is the STMicroelectronics 4001BE (thats right, buffered...!)

I'm not certain why some chips work, and some don't. the internal circuit design of CMOS ic's varies wildly between manufacturers.
but ive found usually that if it works on one gate it works for the rest. although, im sure thats not the case for every ic.

i've gone between using 100k resistors and 47k resistors for R1/2, although i don't think this would cause the differences.

you could also try using 4069 NOTs as your gates instead of NAND/NOR... the only reason i used 4011/4001 was because thats what i had in the random cmos bag .

I do wish the chips werent so variable, but we are trying to build analog audio devices using stuff meant for digital logic. its not going to be ideal by any stretch.

FUN FACT: the suzuki omnichord OM-84 uses a similar set up to get its drums, as shown in this schematic http://www.voxinfinitus.net/~psyingo/OM-84_schematics.jpg at IC15. although,that one is a bridged-t, as opposed to a twin-t.

anyway... sorry i dont have any more concrete advice to give you. i have found that some ic's will give just humming, or distorted bips, or just clicks while some will give the proper percussive sound... :/

analog_backlash · Posted: Fri May 10, 2013 6:27 am Post subject:

Thanks for the reply Psyingo. I'll have to give the 4001B a go. I've got quite a few of those from 3 different manufacturers (but none are STM Sad

). I did try 4069s out, but still had problems. I've been playing with the old Elektor twin-T design posted by YuSynth here:

http://electro-music.com/forum/viewtopic.php?highlight=twint&t=28541

This does work, but I'd like to try your idea again, as it has separate pitch and resonance control. I'll let you know if I have any success (and with what).

Cheers,

Gary

Psyingo · Joined: Jun 11, 2009 Posts: 242 Location: Canada

analog_backlash · Posted: Sun May 12, 2013 2:03 am Post subject:

Thanks a lot for that Psyingo - that's much easier to read than the sketchbook Very Happy

. I'll have another try at this circuit (probably tomorrow, as I'll be out most of today). As I said, I'll let you know how it goes.

Gary

analog_backlash · Posted: Yesterday, at 4:31 pm Post subject:

Sorry for the delay - I haven't given up on this. I tried an HEF4001BP which did seem to work a bit (but not as good as yours did). Many of my other 4001/4011s gave very poor results.

At the moment I'm cheating (Lunetta-wise) and I'm using an LM324 with part of a modified CGS drum design (which I've changed to a single rail supply to make it Lunetta friendly) - see Ken's design here:

http://www.cgs.synth.net/modules/pic/schem_cgs18.gif

I'm still triggering with your 4503 circuit. Would this work with more conventional buffers (e.g. the 4050)? I'll probably give it a go and see what happens. Anyway, I'm getting quite good (tom-tom) drum sounds from this Frankenstein circuit. If it is good enough, I'll post my schematic (making sure to credit everyone involved).

Gary

ufokult · Joined: May 20, 2013 Posts: 3 Location: Finland

oh wow! This sounds just fantastic. I had no idea CMOS stuff could actually achieve anything like this. I'm dreaming of drum machine of my own Razz