AY Crudentials: 8 Bit Samples
Posted: Sat Jan 21, 2006 2:19 pm
The hardware of the Ay-3-8912 can only handle up to 4 bit resolution but may handle up to 8 bit through the mixing of the 3 available channels.
A phenomenon exists that means that when the volume of channel A is set to one value, and the volume of channel B is set to another, the effective single output will not be one or the other, but a fraction higher.
Using this phenomenon it is possible to build up a virtual 8 bit resolution register using a combination of volumes accross the 3 available channels.
However, though 8 bit the speed is greatly reduced because all three volume registers must be sent information for every sample Value.
This reduces the quality of the sample and in my experience, 4 bit played at 10khz is better than 8 bit played at 5Khz.
A phenomenon exists that means that when the volume of channel A is set to one value, and the volume of channel B is set to another, the effective single output will not be one or the other, but a fraction higher.
Using this phenomenon it is possible to build up a virtual 8 bit resolution register using a combination of volumes accross the 3 available channels.
However, though 8 bit the speed is greatly reduced because all three volume registers must be sent information for every sample Value.
This reduces the quality of the sample and in my experience, 4 bit played at 10khz is better than 8 bit played at 5Khz.