Originally Posted by Mrs Beanbag
But Amiga has 4 of them, so combined you can get more than 8 bit. The easy trick is simply to play the least significant 6 bits on another channel at 1/64 volume, giving you 14 bit sound. I don't know how you would get 16 or 18 bit sound but maybe there are other ways.
No, this is not channel folding - this is noiseshaping - quantization noise s pushed to range out of human hearing threshold (or rather there when is less audible - when more than 40ksps is used energy can be shifted out of audible range - for ECS/AGA this related to current H frequency, on OCS perhaps line can be shorten by Copper/CPU or software driven - CPU/Copper mode) - higher sampling make this easier and more efficient but even with normal OCS maximum sampling rate for stereo 8 DMA sound (29073 samples per second) useable dynamics should be around 75 - 85dB which is roughly translated to 13 - 14 bits - even on PC such 8 bit audio sound reasonably nice.