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Sonoff 4CH Pro for speakers?

Hello! 

I'm new to home automation and currently trying to find solutions for my different challenges. 

One thing I'm trying to find is a good way of changing between different sets of speakers in different rooms. I have a normal reciever with an analogue switch today, and speakers in 4 different rooms with cables running to the receiver/switch. 

So my question is if it would be possible to use two Sonoff 4CH Pro (one for left and one for right channel), hook them up to a 5V input through the low voltage port, and then as input use the wire from the receiver, and as output, the four different speakers, all this times two (left right).

Will this work, or are there any doubts about my idea? Or is it better to use some other Sonoff device to fix my issue?  Thanks in advance! 


In theory yes, you can do it with one switch by switching the ground side of each room instead of the L&R channels.  BUT BE AWARE that those speaker switches have impedance matching networks inside to protect the amplifier and speakers.  If you intend to turn sound on in more than one room at a time you will need to duplicate the functions of the analog switch, including the impedance matching, with your IOT switch.  My 2 cents worth is to proceed only if you know what you are doing with the impedance matching.


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Thanks! I have an old analogue speaker switch today, that takes care of the impedance problems, so my idea now is to hook up the Sonoff after the Switch, to take care of that issue. I will open it today to see how it looks and if I can find any other ideas. :-) 

Yeah, it is an interesting application.  The existing switch expects a load to be on each circuit so while hooking  the sonoff up after the switch might protect the amp I suspect you are going to get some significant volume level changes depending on how many rooms you have turned on.   Let us know how it works out!


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Thanks, that is some very interesting input, that most likely I will get rid of the impedance problem no matter how many pairs of speakers I will start, but I will need to adjust the volume. Since my goal is to build scenes for different scenarios, I probably could tweek the volume to be pleasent that way, since I imagine quickly turning off three rooms and keep one on would give a bit of an unwanted "boost"... :) 

My idea now is to do something like this (sorry for the drawing skills...) In this case I have only added one Sonoff 4ch pro, but it should be two, either on per two pairs of  speakers, or one for left one for wright. What the idea is, is to just "cut" one of the two speaker cables, running it through the Sonoff, without using the Sonoff input power, powering it through the 5v input. 

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If it were me I would try it with just one 4ch pro.  The ground or shield wire should be common to both left and right channels on all 4 inputs and outputs.  You can confirm with a meter which should show near zero resistance between any two grounds.


In other words leave the left and right channels connected to the existing switch.  Disconnect the ground wires coming from each room and switch them individually.  If you have two ground wires coming from a room simply tie them together at the sonoff.


But hey, I am no audio expert so take it for what it is worth and do it at your own risk!

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