Quote:
Originally Posted by buggs
Paula's capabilities wrt. actually achievable bit depth in the 14 Bit mode are in the ballpark of 10-11 bit with ECS Paula, depending on the Amiga model. Two major factors contribute to the observed limitations:
a) DAC output levels are not linear with respect to the intended 8 bit source amplitudes
b) the low volume channel is not synchronized in time and actual frequency to the high volume channel due to Paula's implicit resampling at volumes <64
[...]
I've updated my Paula writeup with Details to these measurements. The PDF can be found here
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Thank you for this extremely interesting and comprehensive paper! It never occurred to me that the mismatch between the sampling frequency and the PWM-period introduces noise.
Do you have an estimate what fraction of the total noise is due to that internal resampling? What SNR would be achievable at 55.4 kHz? It's rather pointless for practical purposes because it'S such an uncommon sampling frequency, and good quality resampling probably beyond the capabilities of an Amiga CPU.