Broadcast Audio To Multiple Receivers Via Bluetoot, pairing multiple Bluetooth devices

I want to be able to connect multiple Bluetooth devices to a Bluetooth transmitter, and then stream audio from a portable MP3 player, via Bluetooth, to all of the connected Bluetooth receivers.

1) Is this even possible?

2) I thought of using the A2DP profile to stream audio. But is it possible to stream audio to multiple receivers?

3) I was hoping I could use a Bluetooth module for this, something like Bluegiga WT32. But perhaps I should use a micro controller, maybe an Arduino, instead?

4) To be able to connect more than 7 units to this device, I thought of using three Bluetooth transmitters. But when I pair my Android phone to this device, I don’t want to have to select between the different Bluetooth units. I just want to be able to select the device and be paired with any of the available Bluetooth transmitter.
Any idea of how this is achieved?

5) Is it possible to stream an audio signal to multiple receivers via Bluetooth without pairing the Bluetooth units?

Any help would be of great use! /Johnny

This post has been edited by josabe on March 20, 2013 12:36 pm

Not a clue. Tried Google?

Tim

(Threads merged)

It would appear that it's possible. There is a broadcast mode. From the Bluetooth V2.1 spec:

3.1.1 Framed data traffic
The L2CAP layer services provide a frame-oriented transport for asynchronous
and isochronous user data. The application submits data to this service in variable-
sized frames (up to a negotiated maximum for the channel) and these
frames are delivered in the same form to the corresponding application on the
remote device. There is no requirement for the application to insert additional
framing information into the data, although it may do so if this is required (such
framing is invisible to the Bluetooth core system.)
Connection-oriented L2CAP channels may be created for transport of unicast
(point-to-point) data between two Bluetooth devices. A connectionless L2CAP
channel exists for broadcasting data. In the case of piconet topologies the master
device is always the source of broadcast data and the slave device(s) are
the recipients. Traffic on the broadcast L2CAP channel is uni-directional. Unicast
L2CAP channels may be uni-directional or bi-directional.

To Village Idiot:
Intersting! But is it possible to use both A2DP (which is used when streaming audio) and L2CAP? Or do you mean that I should use L2CAP instead of A2DP?

This post has been edited by josabe on March 20, 2013 12:41 pm

Easy - pair all the receivers with the Bluetooth transmitter.

I worked for The Source (what Canada calls Radio Shack) over Christmas and paired 1/2 dozen receivers to my cellphone. When I'd had enough Christmas carols, I'd have my phone play stripper music in the store and freaked the manager out

In answer to (5), no.

sounds good!

i think it's not possible, not yet..

you can simultaneously connect bluetooth devices. but bluetooth uses spread-spectrum frequency hopping. this makes it impossible, or rare, for more than one device to use the same frequency.

bluetooth have this frequency integrity to avoid the risk of interferences to other devices.

--regards

Soooo, how come I could pair my Sony-Ericsson j108 phone with my earpiece and the players?

*edit*
Here was the player I paired it with ... several of them!

http://www.thesource.ca/estore/product.asp...BDA86DDD7A36692

ooopps...pinned down..

i misread number 5...haha..

thanks for the correction Geek...