push button volume controls?

[sehtime]

im building a project for my industrial design class and cant figure out how to put volume controls using momentary switches, its for a small speaker box for use with any mp3 player using a standard jack. anyone got any ideas?

[Snow_Cat]

Using a digital potentiometer w/ up/dn control up/down counter to vary the feedback-loop on your opamp.

Example of a digi-pot
http://www.intersil.com/data/fn/fn8205.pdf

edit: anac. removed

[limpport]

Send a PM to Life of Brian, he's made some for some of his portables.

[weaponepsilon]

I would have the switches in a series with each one controlling a resistor. That way if you had, say, five momentary switches each one could filter off however many Ohms you need to terminate the signal by the end of the loop. Of course, this is if you are only using momentary switches like you said.

[ABCinc]

http://www.datasheetcatalog.org/datashe ... 51_T_2.pdf" onclick="window.open(this.href);return false;
here's one Brian used.

Edit: Video of it being used. http://www.youtube.com/watch?v=Foxd3nDr8zc" onclick="window.open(this.href);return false;

[weaponepsilon]

If I'm reading the question correctly, sehtime is using switches in lieu of potentiometers.

[Snow_Cat]

Actually,that other chip looks to be a better choice than what I suggested.