As I stated in a previous post, I'm trying to use an embedded 10-bits DAC peripheral of a Cortex-M3 MCU to generate some good audio on a simple 8-ohm speaker.
In order to reduce the audio memory space (it must be saved in internal Flash of MCU), I tried to reduce the bit-depth to 8-bits and I had bad results.
I used sox application to make the conversion of poweron.ogg file (it's a simple audio installed in Samsung Android phones).
sox poweron.ogg -b8 -r 44100 poweron_b8.u8
Now I converted back to 16 bits:
sox -b 8 -r 44100 poweron_b8.u8 poweron.wav
There are a big difference in quality between the original file and the converted file. I can hear a clear background noise.
I think it's the quantization noise. So my conclusion is: 8-bits audio waveforms can't be used for medium-quality (not hi-fi) music. Do you agree with me?
Is there something I can do to improve the conversion from 16- to 8-bits?