dual source input signal to single speaker

[jimtxas]

I have a need to create a relay circuit that allows the following:

2 audio line inputs to 1 audio line input.
For example, 2 input circuits A and B to a relay.
Circuit A has a constant signal that's passed to C (the speaker, or amp input)

when a signal is present on audio Input B, the relay switches to B passing it to C.

We have a security system that relays phone rings, doorbells, etc. We also have a whole house audio system. I simply want to pass on that signal details from the security system to the whole house audio when/if there is a signal present interrupting any other audio.

I know there are whole house audio systems that do this natively but do not want to replace and sure i can do this with some sort of relay setup.

Any recommendations, part numbers that may be needed would be appreciated. i can fire up the soldering iron and put this together with any components required but if there's a device out there that already does this that would be appreciated as well.

 

[TLS Guy]

I have a need to create a relay circuit that allows the following:

2 audio line inputs to 1 audio line input.
For example, 2 input circuits A and B to a relay.
Circuit A has a constant signal that's passed to C (the speaker, or amp input)

when a signal is present on audio Input B, the relay switches to B passing it to C.

We have a security system that relays phone rings, doorbells, etc. We also have a whole house audio system. I simply want to pass on that signal details from the security system to the whole house audio when/if there is a signal present interrupting any other audio.

Any recommendations, part numbers that may be needed would be appreciated. i can fire up the soldering iron and put this together with any components required but if there's a device out there that already does this that would be appreciated as well.

You won't do that with a relay. You need to design a CMOS logic MOSTET switching circuit.

I know that sounds intimidating, but those circuits are actually quite simple if you research it. However if you do not have experience in elementary digital circuit design, it may defeat you.

This is how the systems you refer to work.

If this is beyond your ken, the you need to replace your system.

I know there are whole house audio systems that do this natively but do not want to replace and sure i can do this with some sort of relay setup.

 

[hdi man]

http://russound.com/product_detail.php?i=1769

Russound ab3.2 should do.