Originally Posted By: The Soundsmith
... and is there a limit to the number of listeners - don't see why there should be, but...)

I don't know off-hand if there's a limit in the specification, but certainly many devices will only pair concurrently with a small number ... two or three isn't unusual.

OK, concurrently looking at the specs suggests there are unicast and broadcast modes available, so in principle I think you could get a broadcast device and multiple bluetooth devices can then receive the broadcast. The catch is that you probably need a broadcast-capable device to do it. I guess that most Bluetooth audio devices are capable of receiving such a broadcast.

Transmit power essentially affects range (distance) only, not the number of listeners. Obstructions will reduce the range, so a dense crowd may have some effect. Some Bluetooth systems can do 100 metres or more and I imagine a broadcast device would likely support that.

(Bluetooth Basic Audio Profile: "4.14 Broadcast Audio Streaming", bluetooth.com)

Jazz relative beginner, starting at a much older age than was helpful.
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