mini mixer at ggg

[jimmy]

hi

would that circuit alond be powerful enough to drive headphones, or rather 4 sets of headphones?

im looking at building a headphone amp where four inputs go in, and four headphones come out, but you can hear the other three inputs as well as yours in the headphones.

any suggestions?

thanks
Jim

[petemoore]

I believe that's a simple mixer for mixing inputs.
 There are the Little Gem, LG MkII, and also the Ruby amp at Runoff Groove, Very easy, I've built a few, would have plenty of power [too much?] to drive headphones, I'd think you'd want a volume control on it for headphones.
 But I saw a Headphone amp around, I just can't think where.

[RDV]

Here ya go little feller:
http://headwize.com/projects/index.htm

RDV

[jimmy]

aaaaaahhhh great!! thanks alot for that, exactly what i was looking for.

cheers
Jim

[Mark Hammer]

You can also try going to http://www.paia.com and looking at their headphone distribution amp.

Mixing circuits assume that the signal is going to a medium impedance load next.  Headphones are very low impedance in comparison to this.  Fortunately, a few comemrcial op-amps like the NE5532 and LM833 are able to drive very low impedance loads and deliver enough current to them to produce acceptable volume levels.

[audioguy]

I dont suppose there are any with PCB layouts?