DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: Tony on August 29, 2004, 09:58:39 AM

Title: What is a "gain driven oscillator"?
Post by: Tony on August 29, 2004, 09:58:39 AM
Can anyone explain what that is?

Thanks,
Tony
Title: What is a "gain driven oscillator"?
Post by: Paul Perry (Frostwave) on August 30, 2004, 12:49:57 AM
I have no idea. What context did it come up in?
Sinewave oscillators usually have a loop with a gain control in the loop that adjusts the gain to stay just on the edge of oscillation, to avoid overdriving & keep the output waveform pure. Works down to thousnadths of a % distortion, too!!
Title: What is a "gain driven oscillator"?
Post by: niftydog on August 30, 2004, 01:32:29 AM
all oscillators could be described as "gain driven". Google "Barkhausen criteria " for more info.

Theoretically, you need unity gain and feedback to make an oscillator.

In practise, the gain varies around unity at all times. Positive gain builds up the oscillations, but if let run wild you'll end up with clipping, so when the oscillations get to a certain point, negative gain is needed to keep it under control, then you go to low and need positive gain again... etc etc. ad infinitum.

Maybe the idea is that you can turn off the oscillations or cause the oscillator to clip by affecting the gain of the circuit.  :?:
Title: What is a "gain driven oscillator"?
Post by: ExpAnonColin on August 30, 2004, 05:39:42 AM
I'm guessing you got that off of the parallel universe schematic... what I meant was that the frequency was controlled by the gain.  Man, I wrote that a long time ago... it was me trying to explain something I didn't quite understand.

-Colin
Title: gain driven osc.
Post by: Tony on August 30, 2004, 07:45:08 AM
Quote from: anonymousexperimentalistI'm guessing you got that off of the parallel universe schematic... what I meant was that the frequency was controlled by the gain.  Man, I wrote that a long time ago... it was me trying to explain something I didn't quite understand.

-Colin

Yes, It looks very interesting. What does it sound like?

Thanks for explaining the term.

Tony
Title: Re: gain driven osc.
Post by: ExpAnonColin on August 30, 2004, 10:56:50 AM
Quote from: Tony
Quote from: anonymousexperimentalistI'm guessing you got that off of the parallel universe schematic... what I meant was that the frequency was controlled by the gain.  Man, I wrote that a long time ago... it was me trying to explain something I didn't quite understand.

-Colin

Yes, It looks very interesting. What does it sound like?

Thanks for explaining the term.

Tony

It's hardly a term though, so don't quote me ;)

Go to http://www.nseffects.com.  There are a few clips there.

-Colin
Title: What is a "gain driven oscillator"?
Post by: Boofhead on August 30, 2004, 11:51:32 PM
What is the source of the term?

I haven't heard of it but I could extrapolate like others have.

People make up terms all the time - some stuff you don't have to worry about.
Title: What is a "gain driven oscillator"?
Post by: ExpAnonColin on August 31, 2004, 01:03:47 AM
Quote from: BoofheadWhat is the source of the term?

I haven't heard of it but I could extrapolate like others have.

People make up terms all the time - some stuff you don't have to worry about.

The source is basically that the frequency is determined by the gain-gain driven.  Envelope controlled frequency oscillator would be a better way to say it.

-Colin
Title: What is a "gain driven oscillator"?
Post by: Boofhead on August 31, 2004, 05:16:37 AM
QuoteThe source is basically that the frequency is determined by the gain-gain driven. Enve

I meant where did the original poster find the term written down.   People invent terms all the time - there's a difference between common technical terms and things people make-up on an adhoc basis.   I wouldn't be too worried about the latter.
Title: What is a "gain driven oscillator"?
Post by: travissk on August 31, 2004, 04:38:13 PM
He got it off of Colin's Parallel Universe schematic:

http://www.experimentalistsanonymous.com/diy/Schematics/Parallel%20Universe%20Schematic.gif

-Travis
Title: Gain DRiven
Post by: Tony on August 31, 2004, 07:27:31 PM
Hi,

Yes, I got it off of his site. Very interesting design and great sound. I can hear the oscillation going on, almost like a ring mod.

Thanks,
Tony