Audio out and speaker

I am working on some sort of synth and want to add a speaker output but also a line out, and if I am using line out the speaker should be deactivated. I was thinking that I can use this amplifier: http://makezine.com/images/09/CrackerboxAmp_Schem.pdf and have a switch on the OUT after the Master volume so it can switch between speaker and line out Will that work ok? with no noise or problem at all? Thanks!

Pancra85: I am working on some sort of synth and want to add a speaker output but also a line out, and if I am using line out the speaker should be deactivated. I was thinking that I can use this amplifier: http://makezine.com/images/09/CrackerboxAmp_Schem.pdf and have a switch on the OUT after the Master volume so it can switch between speaker and line out Will that work ok? with no noise or problem at all? Thanks!

You can get jack sockets with built-in switches for doing this sort of thing. Connect your speaker through the socket and when you plug something into the socket it gets disconnected.

With line out.

Oh... so when I connect the line out the speaker gets automatically disconnected? That is awesome. And R9 is the volume, right?

Thanks!!

Yes, R9 is the volume control, but you still need a switching jack socket (or some other means) to disable the speaker.

ok, and where the switch of the audio jack goes connected on that schematic? If it were a normal switch I would think that the switch goes from R7 to speaker, but I have no idea how to do it with a built in switch as it has only one connector.

also, I dont see R7 value and what value should be correct for the R9 potentiometer?

R7 is 1k, R9 is 10k, the switch goes in series with the speaker.

http://en.wikipedia.org/wiki/Phone_connector_%28audio%29#Switch_contacts

Find a jack that will disconnect the amplifier when you insert your line-out phone.

Pretty common.

ok, yes, but where do I connect the switch output of the jack?

Pancra85: ok, yes, but where do I connect the switch output of the jack?

You're OK with the the schematic above but can't wire up a mechanical switch...? :~

Pancra85: ok, yes, but where do I connect the switch output of the jack?

To keep things simple just wire a slide or toggle switch in series with the speaker. One phono socket for input, one jack socket for line out, (you can`t get them mixed up that way).

http://www.ebay.com/sch/i.html?_nkw=jack+socket+switch+3.5mm

Hey, thank you very much to all for the great help and the time! I think I got it now, the jack will act as a jumper when a plug is connected, that goes in series to the speaker.

I'll buy some from ebay!