Mixer

[Michael Cuell]

I've been thinking about building a small mixer so that I can have multiple inputs to one output. I've seen a couple of examples online. Some are quite simply pots wired to jacks. The other kind I've seen has a 9 volt battery. I can't quite figure out what kind of circuit this mixer might have.

Any ideas?

[John Sawyer]

I would envision an active device as having a preamp/ipedance matcher per device, then faders on the output.. one per...  but I've never done this...  

But for $25 is it worth building?

http://www.zzounds.com/item--BEHMX400?siid=38044

[Michael Cuell]

I'll agree, both of those fit the bill.  As I think about it, there's probably a small pre-am or power amp between the input and volume controls.

[TN Twang]

A low-cost "passive" mixer (one that uses no power source) might be a worthwhile cigar-box project. It's one click better than using a Y connector and letting one signal source feed back into the other signal source with questionable results. Plus, you could build it into a little box that's not useful elsewhere and carry on the "made from found objects" image.

Powered mixers have preamps ahead of the mixing pots, and the more money you spend the better the preamps preserve your signal (or so we hope.) Behringer is an excellent source for "semi-pro" gear. I also have a little low-end Yamaha that I use, and Peavey makes some little 4 and 6-channel mixers.

For a powered mixer, it's probably better to shop for a bargain than to build from scratch unless you seriously want to get into analog audio--which is also a great hobby, by the way.