Wireless Audio Transmitter via Bluetooth

Hi everyone,

First off, I am a noobie. :slight_smile:

So I am working on a project that will digitize an audio signal from a standard RCA jack and transmit that signal using Bluetooth to a receiver and then convert it back to an analog signal which I will output to any speaker.

I know that I will need 2 microcontrollers that will handle Bluetooth as a receiver and transmitter. My question is: Should I use two Arduino BT's (for RX and TX) or should I use a different Arduino with the Bluetooth shield (slave). Can I even mix and match with the Arduino BT and Arduino BT SHIELD (slave)? Any suggestions will help. Thank you in advance!

Can I even mix and match with the Arduino BT and Arduino BT SHIELD (slave)?

The physical location of the bluetooth device does not matter.

What WILL matter is that the project is doomed to fail.

The Arduino's analog to digital converter is pretty slow. The sampling rate is too slow to allow even voice quality conversion.

Even if it were high enough, how would you use the digitized data on the other end? The Arduino does not have a digital to analog converter that you can connect a speaker to.

Thank you for your input! Do you have any suggestions for parts to you in this project (transmitter and receiver wise - BT). Which would give the best sampling rate/AD conversion? Thanks!

The point about Bluetooth is that it sends data in packets not continuously. You have your work cut out taking the samples, assembling them into packets transferring them via Bluetooth, taking the packets apart and then feeding them to an D/A at the right rate. You are hampered by the arduino's lack of memory and speed.

If you want to look for parts for the receive D/A end then look at the D/A chip used in the Lady Ada wave shield.
http://www.ladyada.net/make/waveshield/

Is the main problem the Arduino board's speed or simply the fact that Bluetooth data isn't a continuous stream?
What about an X-Bee, or a radio receiver?

Xbee is the same in that data is sent in packets and not continuously. For sound you have to buffer a frame and play it out aysynchronously at the right rate while the next frame comes in. So the arduino is a bit under powered and lacking in memory to do this.

Translate to english, because I talk portuguese.
Eu vou dar uma sugestão (I'll make a suggestion)
Você pode usar um celular para fazer isso.
Entrada de fone de ouvido pode receber um cabo RCA.
O celular pode enviar o sinal Bluetooth para um receptor Bluetooth compatível.
Exemplo: Fone de Ouvido Estéreo Receptor de Bluetooth.

You also might look into converting the signal externally so that you only have to worry about communication in your microcontroller code.

TI makes an 8 bit microcontroller IC which handles audio conversion: TLC7528 data sheet, product information and support | TI.com
I found an instructable about using them too: http://www.instructables.com/id/Stereo-Audio-with-Arduino/

Encode and decode externally, then use the microcontroller to handle the data transmission part, and send the digital signal to the analog converter.

What is the purpose of this project.

Is it just a technical exercise or college project

Why did you decide to use Bluetooth

Basically, if you don't have experience or skill sets in this area, its going to be an extremely steep and lengthy learning process.

If you have do it with Bluetooth, you probably need to use a Bluetooth system module e.g. By CSR but the cost of the development software is $$$$$$

Basically, if you don't have experience or skill sets in this area, its going to be an extremely steep and lengthy learning process.

That is true, especially as this thread was started in 2012.