Inserting things into my nads...

Not sure what to call this, but it's something that I need just for my desk/computer audio setup. I want to be able to send signal from both the headphones out of my computer, and my CD player to one 'channel' of a NAD 7120 Receiver. I want to be able to have level controll on both, so in reality 4 channels of audio. What I see me needing to do is put diodes on all four signal lines and then pots on them. Is this the right way to go about doing this? I basically want to make a mini-mixer type idea, but don't need all the features such as eq . I'm not sure what this is called or I would have searched. If anyone has done this or knows how to, or knows what I am looking for, I would appreciate it. If you have a schematic or pcb layout, even better.

Thank You,
ctardi said:

You can't run 2 amps into 1 pair of speakers keeping it so that both are mixed in stereo

CD drive is usually being used.

And you can't run 2 sources on a amp.. well you can with a pair of y adapters but this all sounds so retarted and waste of time.. why are you doing this again.. who on earth listens to 2 audio sources at the same time ?
It's not that stupid listening to two audio sources, I sometimes used to play games with all sound effects, whilst listening to some appropriate CD music instead of the poor MIDI In-Game music...

You could try it a with two simple stereo potentiometers, and then mix both channels into one... No diodes required. From there on, you can make it as complicated as you want :)

The easy-to-buy solution: A small (studio/DJ) mix panel?


Maybe it's been mentioned, but "y"ing two sources together is not a good idea. There must be a way of at least partly isolating them from each other. Output devices don't take to kindly to being slammed into by another source. There was a great article posted by Masque Sound about that a while back but I can't seem to find it...
This should do the trick. The 10K resistors pad the headphone level and isolate the two sources. The dual-gang pots will allow you to adjust each source. The headphone signal levels are plenty high enough to drive the aux inputs even after 1/2 voltage division with the R's and Pot's.

I've used this circuit many times to feed a tape or CD headphone output to an audio amplifier. Keep the volume on the headphone source fairly low to prevent distortion.

Happy mixing!


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