electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Articles  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links  |  Store
Forum with support of Syndicator RSS
 FAQFAQ   CalendarCalendar   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   LinksLinks
 RegisterRegister   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in  Chat RoomChat Room 
 Forum index » DIY Hardware and Software » Lunettas - circuits inspired by Stanley Lunetta
Drone synth
Post new topic   Reply to topic Moderators: mosc
Page 1 of 1 [15 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
fetideye



Joined: Jun 22, 2015
Posts: 13
Location: Netherlands

PostPosted: Mon Feb 05, 2018 2:38 pm    Post subject: Drone synth
Subject description: cd4049, cd4053 and cd4093
Reply with quote  Mark this post and the followings unread

I've made this drone synth.
2x triangle wave osc's that go through an analog switch clocked at audio rate.
After that comes a simple lowpass filter (based on the filter of the WSG)

It sounds pretty good. growling basses and screaming phasing sounds
https://soundcloud.com/reverselandfill/creep-cluster-1

1 problem: after a while (30min or more) the sounds of the oscillators deteriorate.
This happens sometimes. not with all builds.
-added clicks to the sound
-2nd osc pitch pot has no response


Does anyone know why ?

my guesses:
-inhibit pin cd4053 unconnected? (maybe connect to gnd or +9v)
-cd4053 "A" (control) input gets a too high input voltage from the cd4093 (9v)
-c4 capacitor ?


******note: FIXED! thanks Smile see updated schematic a few posts down


creep.png
 Description:
 Filesize:  37.87 KB
 Viewed:  241 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

creep.png



Last edited by fetideye on Tue Oct 09, 2018 6:27 am; edited 3 times in total
Back to top
View user's profile Send private message Visit poster's website
Blue Hell
Site Admin


Joined: Apr 03, 2004
Posts: 22567
Location: The Netherlands, Enschede
Audio files: 220
G2 patch files: 319

PostPosted: Mon Feb 05, 2018 3:07 pm    Post subject: Reply with quote  Mark this post and the followings unread

Yes. at least the INH input should be tied to ground, to not inhibit the switches. Or otherwise the pin might charge up slowly causing the circuit to not work, or work glitchy.

But also the unused B and C switch control lines should be defined. In this case it does not matter, either to Vcc or Ground (as these control the unused switches, but could still mess things up when unconnected).

_________________
Jan
Back to top
View user's profile Send private message Visit poster's website
PHOBoS



Joined: Jan 14, 2010
Posts: 4088
Location: Moon Base
Audio files: 605

PostPosted: Mon Feb 05, 2018 5:24 pm    Post subject: Reply with quote  Mark this post and the followings unread

Maybe a resistor from the connection between C14 C4 and R15 to GND might also help a bit as it is a connected to a pretty high impedance.
But yeah, as blue hell said connect those floating pins. For the INH pin you could also built another oscillator with one of the unused
NAND gates and attach that to it. You'd probably want to add a switch to choose between the output of that and GND though.

Could go further and use a CD4052. Connect the outputs of the triangle oscillators to pins 3 & 13, connect different resistor values
to the other in/out pins (1,2,4,5,11,12,14,15) and connect those all together to C4. Than add 2 oscillators to the A & B inputs (with
optional switches). Laughing

_________________
"My perf, it's full of holes!"
http://phobos.000space.com/
SoundCloud BandCamp MixCloud Stickney Synthyards Captain Collider

Last edited by PHOBoS on Tue Feb 06, 2018 3:18 am; edited 1 time in total
Back to top
View user's profile Send private message Visit poster's website AIM Address Yahoo Messenger MSN Messenger
Grumble



Joined: Nov 23, 2015
Posts: 795
Location: Netherlands
Audio files: 23

PostPosted: Tue Feb 06, 2018 12:50 am    Post subject: Reply with quote  Mark this post and the followings unread

PHOBoS wrote:
Maybe a resistor from the connection between C14 and R15

C4 Wink

_________________
my synth
Back to top
View user's profile Send private message Visit poster's website
kaputtpanzer



Joined: Nov 02, 2009
Posts: 84
Location: Cologne
Audio files: 4

PostPosted: Tue Feb 06, 2018 2:03 am    Post subject: Reply with quote  Mark this post and the followings unread

Great little Dronemachine! But you have to find some use for the leftover 4093 gates Laughing Cool
Maybe you can build a nice LFO for the WSG Filter..
Back to top
View user's profile Send private message
fetideye



Joined: Jun 22, 2015
Posts: 13
Location: Netherlands

PostPosted: Tue Feb 06, 2018 7:17 am    Post subject: functions Reply with quote  Mark this post and the followings unread

Thanks for all replies!
I'm going to try this.

As far as I understand it, the inhibit is a sort of on/off switch?


About the LFO:
That is a good idea.
I was wondering how I could make the WSG filter CV controllable.

If I would make a LFO for the cutoff, where would I insert it into the filter circuit? (cutoff control)

I've also thought about changing the oscillators to triangle outputs of the 4093 (with some amplification), because the 4049 OSC looses gain fast in higher frequencies.

see here for some fancy boutique models i've made of this project:

This one has multiturn pots for all oscillators, a range switch and a starve pot.
Posted Image, might have been reduced in size. Click Image to view fullscreen.

this one has the drone and a noise generator with touch contacts (and a mixer)
Posted Image, might have been reduced in size. Click Image to view fullscreen.
Back to top
View user's profile Send private message Visit poster's website
kaputtpanzer



Joined: Nov 02, 2009
Posts: 84
Location: Cologne
Audio files: 4

PostPosted: Tue Feb 06, 2018 7:46 am    Post subject: Reply with quote  Mark this post and the followings unread

Beautiful. You can build an emitter amplifier circuit with a npn, and boost the analog signal of the 4093 or you just use another opamp. Look at this thread for adding CV input to WSG filter cutoff: http://electro-music.com/forum/post-387855.html
Back to top
View user's profile Send private message
kaputtpanzer



Joined: Nov 02, 2009
Posts: 84
Location: Cologne
Audio files: 4

PostPosted: Tue Feb 06, 2018 8:13 am    Post subject: Reply with quote  Mark this post and the followings unread

Something like this should work just fine, without distorting the symmetry of the triangle too much. Raise the value of the 1k resistor at the emitter about a few hundred ohms if it distorts.


4093lfo.png
 Description:
Untested, but should work
 Filesize:  91.21 KB
 Viewed:  102 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

4093lfo.png


Back to top
View user's profile Send private message
fetideye



Joined: Jun 22, 2015
Posts: 13
Location: Netherlands

PostPosted: Tue Feb 06, 2018 3:09 pm    Post subject: Reply with quote  Mark this post and the followings unread

I grounded the inhibit & input B & C. looks like that did the trick!
(tested it for one hour, no problems anymore!)

awesome Twisted Evil

Thanks for the help!

I'm going to design a new circuit with more features: (feature creeps)
-4093 triangle oscs (with cv inputs)
-extra squarewave option (2nd switch and mixed into filter)
-external inputs
-modulated clock (cv or extra osc) / PWM
-filter cv
-lfo
-maybe another switch IC (like the DG419)?

let's see how this will work out!

I mention the DG419 because I had some problems with this circuit on +12v (eurorack) A friend of mine told me the cd4053 might not work on this voltage. Does anyone have more info on this?
Back to top
View user's profile Send private message Visit poster's website
Blue Hell
Site Admin


Joined: Apr 03, 2004
Posts: 22567
Location: The Netherlands, Enschede
Audio files: 220
G2 patch files: 319

PostPosted: Tue Feb 06, 2018 4:57 pm    Post subject: Reply with quote  Mark this post and the followings unread

Cool

re. the12V issue - this should just work. The switch is specified up to 18V or so, the INH B C issue might have worked out there differently.

_________________
Jan
Back to top
View user's profile Send private message Visit poster's website
kaputtpanzer



Joined: Nov 02, 2009
Posts: 84
Location: Cologne
Audio files: 4

PostPosted: Wed Feb 07, 2018 6:51 am    Post subject: Reply with quote  Mark this post and the followings unread

I breadboarded the 4093 triangle circuit and I have to say that I don't really like the sound of it. I really love this osc here, it is perfect:
Posted Image, might have been reduced in size. Click Image to view fullscreen.
Back to top
View user's profile Send private message
fetideye



Joined: Jun 22, 2015
Posts: 13
Location: Netherlands

PostPosted: Tue Oct 09, 2018 6:26 am    Post subject: Reply with quote  Mark this post and the followings unread

I'm working on the eurorack version now.

How would you add voltage control to that opamp osc ? (posted above)

because I'm also not really happy with the cd40106 / cd4093 Triangle shape.
It changes shape too much with lower frequencies.
I've perfboarded a Saw VCO (a modified 40106 vco ,originally by synthmonger) which will be the alternative waveform.

ps: here is the working update of the original circuit.


creepfix.png
 Description:
 Filesize:  133.97 KB
 Viewed:  38 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

creepfix.png


Back to top
View user's profile Send private message Visit poster's website
CHRISKELLY



Joined: Apr 08, 2018
Posts: 61
Location: England
Audio files: 3

PostPosted: Thu Oct 11, 2018 9:44 am    Post subject: Reply with quote  Mark this post and the followings unread

I can't help with your question but I just had to say what awesome looking synths you've built!
Back to top
View user's profile Send private message
Grumble



Joined: Nov 23, 2015
Posts: 795
Location: Netherlands
Audio files: 23

PostPosted: Thu Oct 11, 2018 11:48 pm    Post subject: Reply with quote  Mark this post and the followings unread

Why are the two resistors in parallel?
Posted Image, might have been reduced in size. Click Image to view fullscreen.


WhatsThis.JPG
 Description:
 Filesize:  10.43 KB
 Viewed:  619 Time(s)

WhatsThis.JPG



_________________
my synth
Back to top
View user's profile Send private message Visit poster's website
fetideye



Joined: Jun 22, 2015
Posts: 13
Location: Netherlands

PostPosted: Sat Oct 13, 2018 1:26 pm    Post subject: Reply with quote  Mark this post and the followings unread

I think that is a leftover from the adaption of the WSG filter I used.
(I left out the pot for the resonance)
if I leave out the 4.7k , the resonance setting changes a bit. there used to be a 500k pot there.

edit:
I've inserted a trimpot there now. to set the resonance.
those 2 resistors were working, but not really. a small mistake.. thanks for pointing it out!
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic Moderators: mosc
Page 1 of 1 [15 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
 Forum index » DIY Hardware and Software » Lunettas - circuits inspired by Stanley Lunetta
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
e-m mkii

Please support our site. If you click through and buy from
our affiliate partners, we earn a small commission.


Forum with support of Syndicator RSS
Powered by phpBB © 2001, 2005 phpBB Group
Copyright © 2003 through 2009 by electro-music.com - Conditions Of Use