Splitting and combining Line level signals?

[BN]

Hi!

It's been a while since my last post but I feel it's time to get into some active building again.

I need a device that allows me to connect an external monitor/amplifier to my synthesizer but still getting the signal into the PA. In order to keep it simple my intention is to come up with a passive solution.

Here's what I have in mind (grounds omitted in the schematic):


With the switch in the first position it will just split the signal in two. In the other position the idea is to get the stereosignal "unaffected" into the PA and merge the other channel to mono via the two resistors. The "mono-merger" was something I found here.

Will this work or will there be problems due to different input-impedances when using the resistors (IE. the input impedance of the PA-mixer vs. the resistors)?

Thought I'd better ask you guys before I fry something...   

/BN

[Pushtone]

Your over-thinking this. This is exactly what a direct box is for.

Remember the the DI performs several functions like impedance AND level matching as well as splitting the signal.
This allows your keyboard to properly interface with the stage mic snake and the consoles mic-preamp.


The right way is a passive DI with transformer isolation to eliminate ground loop hum.

If you want to build it yourself then start out with a DI schematic.
Otherwise, but a stereo DI box like the one linked above.

[BN]

Ok, thanks.

Then I might just as well buy myself a small mixer with monitor outputs. Not the best thing for my wallet right now but it leaves more time for finishing my stompboxes and that can't be bad!


/BN