[sdiy] Is this a comparator?

[John L Marshall]

Noise gate.
a voltage comparator with a gate or VCA.

Take care,
John
www.sound-photo.com
www.antenna-farm.com

----- Original Message ----- 
From: "Derek Holzer" <derek at umatic.nl>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Wednesday, October 31, 2007 6:33 AM
Subject: [sdiy] Is this a comparator?


> There's a function I want to implement, but I don't know what to call it 
> so I can't start researching the right circuit.
>
> I'd like to compare an incoming voltage with a reference voltage, and only 
> allow the incoming voltage to pass if it's above the reference voltage. I 
> do not want to square the signal, I want to pass it unaltered so long as 
> it's above the threshold of the reference voltage. When the incoming 
> voltage is less than the reference, then the reference voltage would be 
> passed (or none at all).
>
> What is this function called? A comparator? A gate? It's not a logic 
> function, since it doesn't deal with square waves. I imagine it's a simple 
> op-amp trick...
>
> thx + best,
> d.
> -- 
> derek holzer ::: http://www.umatic.nl ::: 
> http://blog.myspace.com/macumbista
> ---Oblique Strategy # 43:
> "Destroy nothing; Destroy the most important thing"
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