[Steven Everett]

I built a Szekeres headphone amp (with the gain stage) and would like to send 2 inputs into it. I have a portable CD player and a midi drum pad that I would like to be amplified by my headphone amp. Both devices have their own volume control. Can I take both Left channels and both right channels, wire them together, and plug them into my Szekeres without burning something up? I don't want to use any kind of mixer if I don't have to. I have burned up so much stuff in the past I've come to the point where I ask before experimenting with electricity.
Thank you,
steve

 

[rickcr42]

well the best way to go would be to use a mixer,even if only a single jfet stage.But if you want to go passive then you could use a simple resistor passive mixer.Just be aware that there will be some signal attenuation

 

[Dusty Chalk]

I second -- use a mixer!

 

[rickcr42]

most basic :
http://www.epanorama.net/documents/audio/mixer.html
http://www.hut.fi/Misc/Electronics/c...linemixer.html

 

[Steven Everett]

Thanks a lot guys for the replies.
I really don't want to use any kind of mixer and what you have proposed looks like a valuable alternative. Will I be disappointed with the attenuation?
steve

 

[rickcr42]

depends on the output impedence of your drum pad and cd player plus the actual value of the mixing resistors.
10 K resistors for the mixing matrix are not bad but 4.7 K would be even better PROVIDED the output impedence of your sources are in the range of 50 ohms.
Ideally you want a 10 : 1 match.
But hey,try it out dude,resistors are cheap