Encoder vs Stepped attenuator

I was just wondering: if it's so hard to find good 12 or 24 position switches isn't it easier just to make an equivalent circuit with an encoder and some kind of LED indication? Actual connection can than be made by relays or transistors or whatever else. Has anybody made that already?
Just a plain interest... yet... :wink:

> Has anybody made that already?

Sure. My TV set has no volume pot, no input switch, just pushbuttons into a logic CPU. Digital mixers are all about replacing pots and switches with logic controls.

> relays or transistors or whatever else.

That's the hard part. Relays are power-hungry, costly, noisy, slow, and not too reliable. FETs distort; the fix is added amplification so the FET hardly feels the signal. There are advantages to dumb old mechanical contacts.

One of the members here, "mcs", sells relay and DAC-controlled audio switches and volume control boards for DIY fun.

Ilya:

http://www.groupdiy.com/index.php?topic=11429&start=0