[linux-audio-dev] Using Jack for "Control Volt" continued

[Paul Winkler]

On Sat, Nov 08, 2003 at 07:50:22PM -0800, iainduncan at telus.net wrote:
> Sorry, forgot to ask a couple of things. 
> 
> Will Jack or other similar APIs allow passing of DC signal?

jack doesn't care what kind of signals pass through it.

> If so, do we have 
> to worry about speakers blowing up or do soundcards protect against DC? 

Most audio circuits include "coupling" capacitors that block
DC voltages. Transformers work too.  I would be amazed if any soundcard
will pass a DC voltage.

> If not, can anyone tell me what the most CPU efficient way of 
> modulating/demodulating a control signal might be? It occured to me that one 
> could just use a very high frequency signal

remember that nyquist theorem limits the frequency to half the 
sampling rate.

 

-- 

Paul Winkler
http://www.slinkp.com
Look! Up in the sky! It's ANCIENT COWARD!
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