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Noob speaker switch circuit design help please!

OPM

Sep 17, 2012
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Hey guys, not sure if this the right place to ask this but hopefully it is!

I am a bit of an electronics noob but I can read basic schematics, am handy with a soldering iron and can follow instructions real well!

Can anyone design a basic circuit for me, tell me exactly what parts I need and how to wire it all up?

The basics of what I am trying to do is a speaker switch: two lots of speaker inputs from source A and B, a simple slider type switch to select between ysource A or B. there then is just one output, based on the switch position.

Once I have my head around that, I want to add a slight complexity to it - an output headphone socket. So: the switch will select source A or B which will output to either the output speaker terminals OR the headphone socket. If there is a headphone connected the output would be the headphones, otherwise the speakers.

I have drawn a simple diagram of what I am trying to achieve.

I do understand that such devices already exist however I have a couple of ideas like this that I am trying to develop into a single project box which has a number of switches, controls etc

Any advice here is greatly appreciated.

Speakerswitch.jpg
 

GreenGiant

Feb 9, 2012
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the switch is easy, all you need is a good quality (low impedance, clean connection) DPDT (double pole double throw) switch, well 2 of them that you can switch together, wire the output speakers to the common side, then one source to one input and the other source to the other input
 

OPM

Sep 17, 2012
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Thanks greengiant

Sorry to be a nuisance but any chance you could show that in a wiring diagram for me. I somewhat understand the terminology but have no idea how it all wires up especially seeing as each source has two pairs (left and right)
 

OPM

Sep 17, 2012
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Thanks Harald. Any possibility of asking you for a wiring disgram showing how the switch is wired and also the headphone Jack?

Thanks a million
 

Harald Kapp

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The diagram shows how the switch is wired (note: the 4 switches in my schematic are actually 4 poles of a single switch).
For the speaker/headphone switch: read this article. Near the end under "Configurations and schematic symbols" look at schematic D. That's what you need to buy. Connect both speaker "-" from my schematic to the sleev (outer ring). Connect the left speaker "+" from my schematic to the second pin from below. Connect the right speaker "+" from my schematic to the top pin.
Connect the speaker "+" pins to the 2nd and 3rd pin from top (the ones that have the full arrow) accordingly.
When no plug is inserted, the switches are closed and you'll have the speakers output active.
If the plug is inserted, the switches are open and the audio is routed to the headphones.

Note that these built-in switches may not be suitable for high power, so the power of the speakers may be limited.
 

OPM

Sep 17, 2012
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Thanks Harald, think I understand now.

I have one last annoying request.

Can someone show how exactly I wire to and from the pins of the switch, jack etc.

While I can look at the schematic I do not understand how for example the 8 input speaker cables wire to which terminals on the switch etc

All help is greatly appreciated
 

Harald Kapp

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That's as far as I can go:
attachment.php


This works under the assumption that your amplifiers allow conencting the - poles of the speaker outputs to a single connection. If not, you cannot connect the headhones in that way. You will have trouble connecting headphones in that case anyway because most consumer headphones have only three pins (common return) You will be hard pressed finding a 4 pin headphone.
 

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