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 
Live streaming at radio.electro-music.com

  host / artist show at your time
  Faux Pas Quartet and friends Music From Last Thursday
Please visit the chat
 Forum index » DIY Hardware and Software » Lunettas - circuits inspired by Stanley Lunetta
I Wanted To Run Something By You Fellows
Post new topic   Reply to topic Moderators: mosc
Page 1 of 2 [28 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Goto page: 1, 2 Next
Author Message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Wed Jul 04, 2012 3:45 am    Post subject: I Wanted To Run Something By You Fellows
Subject description: My First Original Plan
Reply with quote  Mark this post and the followings unread

Good Morning from GMT -5:00

So I've worked up a 2-stage idea that I would like to discuss the feasibility of. I will present stage one first, to make sure that it is sound, and if it is, I will bring out the whole idea.

In the attached schematic, I've drawn out a capacitor whose two leads can be switched simultaneously from power lines to a noise circuit of any kind. The idea is that you switch the capacitor into charging position, then switch it over and listen to the capacitor die out through the circuit.

Does that seem like it would work? Would 10 uF probably be enough for a semi-simple noise circuit to run for about 15 seconds?

Thanks for looking.


IMG.pdf
 Description:
The only thing to mention here is just to make sure it's clear enough that the two switches can only be operated simultaneously.

Download
 Filename:  IMG.pdf
 Filesize:  145.36 KB
 Downloaded:  114 Time(s)

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



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Wed Jul 04, 2012 6:23 am    Post subject: Reply with quote  Mark this post and the followings unread

While that would work the usual method to get say a hi-hat or cymbal sound from a noise circuit is to put it through a voltage controlled filter controlled with an envelope- which is basically a capacitor charged and discharged by a circuit Smile
To calculate the time the noise circuit would operate for, calculate the discharge time of the capacitor; T=RC, R in this case being the resistance of the noise circuit which one cannot simply measure with a multimeter unfortunately.
This method is used in some lunetta circuits to give the circuits in question a voltage starving pulse, resulting in nice weird sounds Smile In my experience something like 1000uF only makes them last for about 5 seconds or less.
You may also want to connect one side of that capacitor to ground, along with the ground connection of your noise circit, then you only need one SPDT switch (single pole double throw) to connect the capacitor either to +V or to the circuit it is intended to discharge through.
The simplicity of this idea for creating some kind of envelope or pulse of sound is appealing, I'm interested to see where this goes Smile

_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Wed Jul 04, 2012 7:39 am    Post subject: Reply with quote  Mark this post and the followings unread

Ah, good. Very Happy It sounds like I'll be stacking a 1F capacitor in there if I can find one. I may also include a progress LED for charging time if it proves to be more than a few seconds.

The overall idea with this device is that it is activated by the light from a match, and when you activate it, you listen to a big capacitor fizzle out like a drop of water on a hot frying pan.

The "full" schematic is attached, and if anyone knows much about flip-flops, I would like to know how exactly they are implemented. I've seen a brief article about them and I know their function. In my situation, I'm using one pulse to close a circuit. A flip flop could gate a transistor to accomplish this task.


IMG_0001.pdf
 Description:

Download
 Filename:  IMG_0001.pdf
 Filesize:  185.79 KB
 Downloaded:  101 Time(s)

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



Joined: Jun 11, 2009
Posts: 247
Location: Canada

PostPosted: Wed Jul 04, 2012 9:10 am    Post subject: Reply with quote  Mark this post and the followings unread

do you want to hear the noise source decay in amplitude over a period of time?
Back to top
View user's profile Send private message Visit poster's website MSN Messenger
JingleJoe



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Wed Jul 04, 2012 12:33 pm    Post subject: Reply with quote  Mark this post and the followings unread

look into the 4066 analogue switch, you may find that as useful for doing what you are doing Smile
However, if you want the light to control the sound, then I believe the conventional method would be to use the light dependant resistor to control a VCF or VCA into which the noise is fed.
What I'd do here is forget about the flip flop and use a comparator to sense the light falling on the LDR, which will switch in the charged capacitor using the 4066, when the light goes above a certain level! Very Happy Fun times will be had by all Smile
There's a good number of descriptions of comparators around the web which use a comparator as a light sensor in the demonstrations Wink

_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Wed Jul 04, 2012 5:32 pm    Post subject: Reply with quote  Mark this post and the followings unread

Quote:
do you want to hear the noise source decay in amplitude over a period of time?


Yes I do. Like a drop of water in a frying pan! Very Happy

Quote:
conventional


Quote:
light dependant resistor to control a VCF... switch in the charged capacitor using the 4066


The switch has got to stay closed until the next time you charge the capacitor.
Would this do that?
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Wed Jul 04, 2012 7:46 pm    Post subject: Reply with quote  Mark this post and the followings unread

Let me refine what I said in the previous post Shocked . I have family at my house and they started to eat watermelon in my ears, so I finished the post in a hurry and got the hell out of there. I don't think I was making any sense. Confused

I just reviewed the 4066 datasheet, and I can't really tell the behavior of the sets of 3 pins that form a switch (one receives the high or low state, and the other two are the signal path to be switched). The way it looks to me is that the circuit is only "closed" during a high state on the switch pin. Immediately after the state goes low, the switch is closed. I may be misunderstanding the datasheet or something you said, but that is not actually the behavior I want. I would like the circuit completion to be maintained even after the falling edge of the trigger pulse.

The thing the match will do is to indefinitely (long after the match burns out) close the switch, until the capacitor dies, which could be 15 seconds or so.

Perhaps this is already what you were advising me for. I am not able to accurately process all of this new information, even when there are no watermelons being eaten rudely in my vicinity.
Back to top
View user's profile Send private message
Psyingo



Joined: Jun 11, 2009
Posts: 247
Location: Canada

PostPosted: Wed Jul 04, 2012 7:50 pm    Post subject: Reply with quote  Mark this post and the followings unread

I'm not sure how complex you want this, but i have a schematic that combines the elements of a noise source, a vca and a decay envelope that could create this... I could upload it.

It could alternatively be used as a snare/cymbal sound Smile
Back to top
View user's profile Send private message Visit poster's website MSN Messenger
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Wed Jul 04, 2012 8:03 pm    Post subject: Reply with quote  Mark this post and the followings unread

Oh, I see. I found a VCA, which stands for Voltage Controlled Amplifier (?) and it is this item that would cause the signal to sound like it's dying out as opposed to simply stopping abruptly (correct?). I didn't realize that one was necessary - I thought the dying out sound would happen naturally. In this case I am interested in your VCA circuit.

On further inspection: "decay envelope." Is it some combination of this and a VCA that makes a fizzle? I think it would be really good if I could have that schematic to look at as I can't picture how they'd be used in conjunction. Thanks Smile
Back to top
View user's profile Send private message
Psyingo



Joined: Jun 11, 2009
Posts: 247
Location: Canada

PostPosted: Wed Jul 04, 2012 9:07 pm    Post subject: Reply with quote  Mark this post and the followings unread

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

heres the schematic. this isnt tested, but i have built all of those circuits seperately. the noise itself was tested at 12v so you may need to tweak r4 and r5 to be smaller. r2 should be a small value, say between 100 ohm and 1k ohm. r1 can be something large like a 100k pot orsomething.
Back to top
View user's profile Send private message Visit poster's website MSN Messenger
JingleJoe



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Thu Jul 05, 2012 1:20 am    Post subject: Reply with quote  Mark this post and the followings unread

Quick helpful suggestion, if you don't know what envelopes, VCFs and VCAs are then look up the standard modules of a synthesizer and thier function. It will reveal the solution to many sound generation mysteries Smile

P.S. a picture speaks a thousand words.


SIMPLE NOISE MAKER.png
 Description:
Here is a schematic for what I was talking about earlier, untested.
 Filesize:  262.54 KB
 Viewed:  5090 Time(s)

SIMPLE NOISE MAKER.png



_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Thu Jul 05, 2012 5:40 am    Post subject: Reply with quote  Mark this post and the followings unread

I went off reading about envelopes, and I don't think that my device will need one. I thought that a capacitor would provide its own sort of exponential envelope. However, I do need a VCA, so thanks Psyingo. Very Happy

And JingleJoe, the large triangle in your schematic: is it a comparator? If it is a comparator, then would it send a momentary 1 (inverted 0) over to the 4066 while the photoresistor is letting more current through than the other resistor?

The 4066. That's what I still don't get. Does the 4066 stop allowing the current through after the high event ends? I can not decipher its datasheet.
Back to top
View user's profile Send private message
Psyingo



Joined: Jun 11, 2009
Posts: 247
Location: Canada

PostPosted: Thu Jul 05, 2012 7:24 am    Post subject: Reply with quote  Mark this post and the followings unread

Without an envelope a vca is sort of useless for what you need. If you are just going to power starve the noise with a large power cap, you wouldn't need the Vca, but you may encounter some problems. You may get a loud click everyone the circuit is activated, also the cap is fairly large. On the plus side the circuit would be slightly easier opposed to the one i proposed. With the decay circuit in my schematic you wouldn't need such a large capacitor and the decay time is also adjustable. you're right in that you don't need a proper envelope, but decay is handy for this.
Back to top
View user's profile Send private message Visit poster's website MSN Messenger
JingleJoe



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Thu Jul 05, 2012 7:42 am    Post subject: Reply with quote  Mark this post and the followings unread

Captain_Clams wrote:

The 4066. That's what I still don't get. Does the 4066 stop allowing the current through after the high event ends? I can not decipher its datasheet.

The 4066 is an analogue switch, basically a regular switch but controlled by voltage, in this case logic or digital voltages of 1 and 0 Smile a switch in the 4066 will be closed when the control input is 1 and open when it is 0.
It has some resistance but it is minor enough not to effect most circuitry.

The triangular component is indeed a comparator, might be an idea to read up on electronic component symbols while you're reading up on synthesizer modules Cool It doesn't produce a pulse but will activate the noise circuit when light falls on the LDR, the large capacitor will discharge through the noise circuit.
Anyway, Just wanted to clarify my idea, psyingos circuit is better in many aspects.

_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Thu Jul 05, 2012 7:46 am    Post subject: Reply with quote  Mark this post and the followings unread

I like the purity of a decay caused by a capacitor losing power. (also the simplicity is good for my inexperience Cool )

For the loud click, I agree. This chart of capacitor discharge time is relevant:

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

That initial quick dropoff would not be very perceivable as it happens so quickly. POP.

So could a guy stick a voltage regulator after the capacitor so that it rides at a steady voltage until it cannot produce that voltage, and then drops off? That would increase the amount of time it will run for as well. Very Happy But will it work?

Oh, and Joe:

Quote:
closed when the control input is 1 and open when it is 0.


I want the circuit to be closed even after the match has burned out. It doesn't sound like the 4066 does that, based on what you said there and what I think ( Rolling Eyes ) I've inferred from the datasheets.
Back to top
View user's profile Send private message
JingleJoe



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Fri Jul 06, 2012 2:51 am    Post subject: Reply with quote  Mark this post and the followings unread

Ah okay, I didn't get that when I read your description, a one shot or monostable is what you want then Smile you could still use the same control method, just have the comparator activate the monostable.
The charge and discharge voltage of a capacitor in a monostable circuit can be buffered and used as an envelope.

_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Sat Jul 07, 2012 8:33 pm    Post subject: Reply with quote  Mark this post and the followings unread

Hey, I finally got back after a day of fiddling with a videorecorder (and also wandering around in Baltimore today). I have something to show you! This is all very exciting to me, as it's my first functioning noise circuit. The video consists of simply a short demonstration of a charge and discharge of the 10,000 uF reservoir capacitor into the 555 timer square wave oscillator.

http://www.youtube.com/watch?v=-AiY1ObS4G8

I have a few questions about the "envelope" that the capacitor brings about. First: the capacitor is rated at 25V, and before the circuit is a 5V regulator (to not melt the 555 timer or whatever else might happen, don't want to find out). I would be expecting the "solid line" from this graph I whacked together with a trackpad on a dirtbag Macintosh with spinoff MSPaint "Paintbrush"

Posted Image, might have been reduced in size. Click Image to view fullscreen.
Dotted line: unregulated discharge of any capacitor
Solid line: discharge of 25V capacitor w/ 5V regulator


So, is what I'm experiencing with this circuit probably my anticipated solid line?

Second: Why is there only a minimal difference in sound between charging the capacitor for 30 seconds and charging it for 2 seconds? Does it really charge up that fast? It's 10,000 uF, and there's even a small resistor that the capacitor charges and discharges through... I would expect it to take longer than 2 seconds to fully charge.

Anyway, I'm really jazzed up about this project now, and I'm looking forward to making it more exciting over time, with a little help from you fellas, that is Wink
Back to top
View user's profile Send private message
inlifeindeath



Joined: Apr 02, 2010
Posts: 315
Location: Albuquerque, NM

PostPosted: Sun Jul 08, 2012 8:00 am    Post subject: Reply with quote  Mark this post and the followings unread

25V is just the maximum voltage rating of the capacitor.
_________________
http://www.youtube.com/user/borisandfef
Back to top
View user's profile Send private message Visit poster's website
attdestroyers



Joined: Mar 29, 2012
Posts: 41
Location: Malvern, Ohio

PostPosted: Sun Jul 08, 2012 9:23 am    Post subject: Reply with quote  Mark this post and the followings unread

Quote:
So, is what I'm experiencing with this circuit probably my anticipated solid line?


I would think it would look more like this. Could be wrong though.


gnzOo.png
 Description:
 Filesize:  17.07 KB
 Viewed:  70 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

gnzOo.png


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



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Sun Jul 08, 2012 10:14 am    Post subject: Reply with quote  Mark this post and the followings unread

Quote:
25V is just the maximum voltage rating of the capacitor.


Does that mean (ideally) that there's no difference in the way any two given 10,000 uF capacitors discharge?

Quote:
I would think it would look more like this. Could be wrong though


Then what happens to these electrons? (see attachment)


gnzoo_104.png
 Description:
 Filesize:  18.69 KB
 Viewed:  68 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

gnzoo_104.png


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



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Sun Jul 08, 2012 10:23 am    Post subject: Reply with quote  Mark this post and the followings unread

inlifeindeath wrote:
25V is just the maximum voltage rating of the capacitor.

Yes, did you acctually charge the capacitor to 25 volts? then discharge it into a voltage regulator? if so you will just get the curve drawn by attdestroyers.
If not, it will just be charged by the 5 volt regulator to 5 volts.

_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Sun Jul 08, 2012 10:29 am    Post subject: Reply with quote  Mark this post and the followings unread

I don't have a multimeter currently (the quality of that Walmart one was inexcusable), but I believe that I had the capacitor charged "all the way up," whatever voltage that may occur at.

The capacitor was not being charged through the voltage regulator, however it was being discharged through one into the main circuit.

I still don't see what could happen to the electrons I colored blue there in the latest graph drawing. Am I looking at it wrong?
Back to top
View user's profile Send private message
JingleJoe



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Sun Jul 08, 2012 10:37 am    Post subject: Reply with quote  Mark this post and the followings unread

In short, the electrons in your graph are not there and if they are, they are regulated down to 5 volts.

The capacitor will only charge to whatever voltage you apply to it and even then only to within about 99% of the voltage in a time equal to 5*RC, it never quite reaches 100% of the voltage applied but it gets to within a tiny fraction.

If you discharge say, 25 volts into a 5volt regulator, it will output 5 volts untill the capacitor voltages goes below 5 volts, because that is what they are made to do: take in any voltage up to a certain limit and output thier stated voltage. Below that voltage things get iffy and to avoid damage to the regulator or improper opetation, one should not really power a regulator with less than the regulated voltage +2V.

_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Captain_Clams



Joined: Jul 02, 2012
Posts: 43
Location: MD, USA

PostPosted: Sun Jul 08, 2012 10:45 am    Post subject: Reply with quote  Mark this post and the followings unread

So when a 5V voltage regulator sees 6V, it passes 5V and kills 1V somehow? As heat perhaps? They do seem to have rather large metal wings on them.

Oh, a more pertinent question to ask would be whether or not there is any way to cause the discharge of the capacitor to happen linearly, or at least a little bit closer to logarithmically.

Either one is better than steady for 10 seconds then fuzzing out all the sudden in a half second.
Back to top
View user's profile Send private message
JingleJoe



Joined: Nov 10, 2011
Posts: 878
Location: Lancashire, England
Audio files: 14

PostPosted: Sun Jul 08, 2012 11:23 am    Post subject: Reply with quote  Mark this post and the followings unread

Capacitors charge and discharge with an exponential or logarithmic curve. It's your circuitry which is having unusual behaviour, maybe when it gets below a certain voltage it simply stops working and works fine above that voltage. Most lunettas can work down to 3 volts and when under that voltage they do strange things and some stop working entirely. When you under power something it is not working as it should, it's not good for your chips and unusual currents may be flowing due to the internal transistors inside your ICs functioning improperly, this causing it to drain the capacitor faster as the voltage gets lower and thus turn off the circuit faster. Assuming you are using ICs.
_________________
As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"


Green Dungeon Alchemist Laboratories
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: mosc
Page 1 of 2 [28 Posts]
View unread posts
View new posts in the last week
Goto page: 1, 2 Next
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