Make 8bit audio sound good?

Special Interest Groups Audio Processing
1

I need to encode music to 8bit mono wav files for playing over a phone system. Does anybody have suggestions that would make this sound as good as possible? I know it’s never going to sound hifi, but if I convert a 16bit file to 8bit with no processing, I get the following artifacts:

  1. A background hiss somewhat like tape hiss.
  2. Audio levels sound like they max out often making the audio sound muffled.
2

8bit audio is tricky. I’m assuming you get to use the 44.1KHz sample rate (lucky), so you shouldn’t have to worry about the frequency response.

To get the best sounding 8bit audio, you need to do two things:

  1. Make damn sure the audio is as clean as possible before and after converting. Use the Sound Removal tool liberally.

  2. Compress the hell out of the audio before converting. Use the compressor starting with a -30dB threshold and a ratio of 10:1. Experiment with these to your ear’s content. This will make the music sound like crap, but it’s the only way to get a halfway clean signal.

The problem with 8bit audio is that you’ve only got 48dB of dynamic range before you hit the noise floor, so you need to make sure all of the audio you want to hear is within that range. You’ve also got to deal with the distortion inherent in a low bit depth signal.

The best 8bit music comes out of an NES. Converting high quality music down to that level brings with it a whole mess of problems.

3

Newbie question folks,

"The best 8bit music comes out of an NES "; would you please explain what “NES” means?

Thank you

Goony :question:

4

If that’s a serious question, then I assume you weren’t a child in the 80’s like I was. :wink:

NES