Rx bluetooth audio & overlay audio with voice commands before amplifying

How difficult would it be and what would be involved to design and build some hardware and software that:

  • Receives bluetooth audio from a MP3 player such as an Apple Nano
  • Intercept the audio with short voice commands stored in flash memory (preferably crossfaded)
  • Send the resulting audio to an amplifier to wired headphones

See the attached high level block diagram.

I have experience with writing low level software on the dsPIC33EP and have access to the fully licensed XC16 compiler. I also have experience in hardware design so I could design a schematic and PCB.

The device will need to be as small as possible, low power consumption and the headphones would be used in a fairly noisy environment (inside a helmet) so the amplifier would need to be powerful enough to compensate for that.

I’m really not sure how to implement hardware and software to receive bluetooth audio and then override the bluetooth audio with voice commands (cross faded) though. I’ve experience with SPI, CAN, RS232, ADC, DMA, DAC etc for use in embedded controllers. But I have little to no experience with bluetooth and playing pre-recorded audio stored in flash (internal or external). This is the area I need the most help with.

BTAudio.jpg

I'm really not sure how to implement hardware and software to receive bluetooth audio

None of the bluetooth shields that I am aware of can handle the volume of data required. The bluetooth device is normally connected to a serial port, which is far too slow to manage audio data.