electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links
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
Voltage Comparators in Synth DIY
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [5 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
Danno Gee Ray



Joined: Sep 25, 2005
Posts: 1351
Location: Telford, PA USA

PostPosted: Mon Jan 14, 2008 2:41 pm    Post subject: Voltage Comparators in Synth DIY
Subject description: UA710's useful?
Reply with quote  Mark this post and the followings unread

Are UA710 voltage comparators useful in Synth DIY? I have a bunch of them on some boards I'm parting out. I was just wondering if they have any utilitarian purpose here. Any schematics to illustrate their use?
Back to top
View user's profile Send private message
françois



Joined: Dec 23, 2006
Posts: 139
Location: Paris (France)
Audio files: 1

PostPosted: Wed Jan 16, 2008 2:04 am    Post subject: Reply with quote  Mark this post and the followings unread

Hello,

Comparators are indeed useful, but usually you can replace them with standard opamps. This is normally not recommended because comparators are much faster and normally glitch free, but at audio rates this does not matter too much.

You can use comparators everywhere an opamp is used as such : VCO sync circuits, VCO reset (discharge) trigger, envelope generators, waveshapers... If you have some µA710s at hand, they might be really useful.

- françois
Back to top
View user's profile Send private message
Danno Gee Ray



Joined: Sep 25, 2005
Posts: 1351
Location: Telford, PA USA

PostPosted: Wed Jan 16, 2008 6:40 am    Post subject: Reply with quote  Mark this post and the followings unread

Thank you. Does anyone have any schematics for examples?
Back to top
View user's profile Send private message
frijitz



Joined: May 04, 2007
Posts: 1734
Location: NM USA
Audio files: 54

PostPosted: Wed Jan 16, 2008 7:27 am    Post subject: Reply with quote  Mark this post and the followings unread

Wasn't there a thread about this just a couple of weeks ago? This chip has "special" PS requirements: +14 / -7 V max. You would probably be better with the LM311.

Very Happy

Ian
Back to top
View user's profile Send private message
robthefiddler



Joined: Nov 10, 2006
Posts: 16
Location: Dallas, Tx

PostPosted: Wed Jan 16, 2008 8:24 pm    Post subject: A project with Comparators 339s to be exact
Subject description: follow up to synth circuits using comparators
Reply with quote  Mark this post and the followings unread

Here is a link to an experiment I did using the 339. The basic idea is the same as the light bar circuit that comparators are so good for. I was going for a way to quantize a pots value (with lots of blinky lights). A good example of this would be a synth that uses a knob to switch between a square, triangle or sine wave.

http://www.robthefiddler.com/electronics-audio-diy/circuit-experiments/using-the-lm339-to-make-a-discrete-selector/

What I ultimately ended up with was something a bit different. Its a noisemaker with a "Mode" knob. Each mode tweaks the signal a bit more.

The comparators are still more used in the control of the signal and not the actual generation. Videos and samples are available.

Still, If I were to try and use this idea again, I would be better of with a PIC as it would be easier to make the modes exclusive in selection as opposed to progressive. (a, b, c) versus (a, ab, abc)...if that makes sense.

Posted Image, might have been reduced in size. Click Image to view fullscreen.


Comparators are also great for PWM.

_________________
www.robthefiddler.net
Back to top
View user's profile Send private message Visit poster's website Yahoo Messenger
Display posts from previous:   
Post new topic   Reply to topic Moderators: jksuperstar, Scott Stites, Uncle Krunkus
Page 1 of 1 [5 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
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


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