[sdiy] Proximity volume control.

[Scott Gravenhorst]

peter edwards <synth at casperelectronics.com> wrote:
>I'm working on a series of synth podiums for a show coming up in a  
>few months. I want the volume of each podium to increase as the  
>viewer approaches it, or at least (worst case) to turn on when they  
>are standing in front of it. I think a range of 1-2 feet is necessary.
>I've been thinking about different methods. IR distance sensors or  
>something of that sort could work but would require lots of  
>processing hardware. I think that capacitive sensing would work fine  
>and would ultimately be the cheapest and easiest option. Thoughts?
>
>I couldn't find schematics for "capacitive volume control" or  
>"proximity volume control" so I started looking into "theremin volume  
>control". This seems to be what I want, but I think theremin range is  
>calibrated for approx 6"-1' right? I also want to set it so that the  
>volume increases as the viewer moves closer and produces NO sound  
>when there is no one standing close to the podium.
>Has anyone else here worked with this kind of circuitry? I'm hoping  
>there's someone here I could chat with for a few minutes. thanks!

One of the functions of a Theremin is to control the instrument's volume with a
proximity detector.  You might find it useful to research the Theremin on the web.


-- ScottG
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-- Scott Gravenhorst
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