I'm considering streaming music/voice over Bluetooth serial link (via HC05) from PC to Arduino. By doing this, there would be no need for a SD card. Here is the questions I have.
Any help is appreciated.

1- Arduino Uno doesn't have D2A. Is the tone.h library enough for this purpose? Can we use an external D2A instead? What about other Arduinos?

2- Maximum supported baud rate for ITead's HC05 is 460800 (datasheet here).
Based on searching the net, people suggest using a lower baud rate to increase Signal/Noise or even range. Does UART's baud rate(aka a logic layer) affect range/quality?

3- If we use 460800, we get 45 KByte/s data rate. If we use 115200, we get 11.25 KByte/s data rate. Are these rates enough for A- Voice and B- Music streaming?

Various audio quality samples are provided here (from 8Kbps to 192Kbps).
Here is a list within reach of HC05's maximum baud rate:
1 KByte/s -> voice, music
2 KByte/s -> voice, music
10 KByte/s -> voice, music

10 KByte/s or 80 Kbps corresponds to baud rate = 115200 and we can quite clearly hear the contents. So can we say baud rate is not the limiting factor here?


  • \$\begingroup\$ And C, why do you think an Arduino would be any kind of a match for this task? \$\endgroup\$ – JRE Nov 25 '16 at 22:13
  • 1
    \$\begingroup\$ Telephone voice (ISDN) is 64kbit per second. That's 8 bit samples, 8000 per second. CD quality is 44100 samples per second at 16 bits per sample - times 2 for stereo. Do the math, and consider how you plan to squeeze that much data through your bluetooth link, and how you expect the Arduino (with no DAC) to do anything useful with it. \$\endgroup\$ – JRE Nov 25 '16 at 22:37
  • \$\begingroup\$ Think about streaming MP3. Try searching "MP3 decoder IC" or "Arduino MP3 decode". \$\endgroup\$ – rioraxe Nov 25 '16 at 22:45
  • \$\begingroup\$ @JRE What is the technical reason that makes Arduino incapable of this task? I'm also considering an external DAC. And based on bitrates raw numbers, it seems at least a decent voice connection could be established @ 11KBps \$\endgroup\$ – Zeta.Investigator Nov 26 '16 at 3:43
  • \$\begingroup\$ Just for a test, download Audacity, and use it to resample a piece of music or voice to your estimated bit rates. Have a listen, then decide for yourself whether that is good enough. \$\endgroup\$ – JRE Nov 26 '16 at 13:21

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