I have been trying to connect two amplifier boards that I took from some mobile speakers. What I want to achieve is to be able to connect to only one via Bluetooth, and have it connect to the other as well.
Both boards have Bluetooth signals as input. Try to connect the antennas of the two boards, so if one of them received the Bluetooth signal, the other would also receive it.
In the photo you can see the idea I had. In the photo you can see everything already disconnected, but I tested everything well soldered, with the two boards on, with each one with its respective outputs, and connecting via Bluetooth to only one.
What I thought was that it made a lot of sense, and that it should work, but no, I only heard the output of the board to which it was connected via Bluetooth, and nothing from the output of the other board.
Does anyone know how this could be done?
Both boards have Bluetooth signals as input. Try to connect the antennas of the two boards, so if one of them received the Bluetooth signal, the other would also receive it.
In the photo you can see the idea I had. In the photo you can see everything already disconnected, but I tested everything well soldered, with the two boards on, with each one with its respective outputs, and connecting via Bluetooth to only one.
What I thought was that it made a lot of sense, and that it should work, but no, I only heard the output of the board to which it was connected via Bluetooth, and nothing from the output of the other board.
Does anyone know how this could be done?
I don't think this is possible. AFAIK when a couple of BT speakers can share a signal (playing stereo, or double mono) one speaker connects to the source and the other speaker connects to the first speaker. I don't think 2 speakers can listen to the same output stream. BT connections have security to prevent that sort of thing.
Bluetooth is a network protocol, packets go both ways to/from the antenna, you can't share an antenna between two device or they'd both drive the antenna simultaneously and likely blow each others RF RX and TX amplifiers...
I have always thought this was a major flaw with bluetooth speakers. Some (Sony) do something special to let you connect multiple but I wish it was just part of the standard.
There's all sorts of other bluetooth weirdness too... I had a car that could only do phone calls, not stream music over it. But you could trick it into streaming music with a special app that pretended it was a phone call.
There's all sorts of other bluetooth weirdness too... I had a car that could only do phone calls, not stream music over it. But you could trick it into streaming music with a special app that pretended it was a phone call.
I think what you need is a single Bluetooth receiver, with stereo outputs. Then each output is connected to an amplifier channel, and then to the speaker. To the best of my knowledge, and as confirmed by others above, Bluetooth can only work with a single pair of devices. One device to send, one device to receive. You cannot have one device sending to multiple receiving devices.
But I am looking to somehow use only one of the Bluetooth receivers, and connect that same signal in some way to the part of the board where the signal should enter to be amplified, and then go to the speakers. I don't know if I explain myself
So you look for the ic near the speaker terminals.
You find the data sheet for that ic.
You connect the inputs of that ic on each board together, using dc blocking capacitors as required and screened cable.
On the slave board you also ensure the input to the ic is not receiving signal from the bluetooth part of its board (by cutting traces).
You will probably find each speaker will be a different volume due to different gain from each board.
You find the data sheet for that ic.
You connect the inputs of that ic on each board together, using dc blocking capacitors as required and screened cable.
On the slave board you also ensure the input to the ic is not receiving signal from the bluetooth part of its board (by cutting traces).
You will probably find each speaker will be a different volume due to different gain from each board.