English Amiga Board - View Single Post - Amiga "14-bit audio" refuted

ross · 14 January 2021, 17:30

Problem here is that Paula is a strange beast, it's not like the usual PCM or PDM emitter of today. It' a mixed PCM/PWM state machine, prone to distortions due to her inner working. Add to this: specific period granularity, different phase for the channels, different filters, different components, different D/A separations, home made 'software' linear calibration (that any technician would shiver to conceive such 'unreliable' thing

)... Many of these properties are not bad per se (far from it!) but they make it difficult to compare it with the existing.

Yes, you can measure the 'math quality' of the sound and decide that Paula is 10, 11, 12 bit or alike (I am not among those who think it is even remotely similar to 14 or 16bit).
But the 'reconstruction' that Paula do from the discrete quantized bits is pretty unique and not so simply comparable with the existing.
What are the conditions that allow it to perform at its best in the 'emulation' of the original signal? I don't think there is anyone here with a precise answer..

So blind test is probably a path to try (as mentioned in a previous message)

.
But under the conditions of the first post Thomas is right.

14 January 2021, 17:30	#78
ross Defendit numerus Join Date: Mar 2017 Location: Crossing the Rubicon Age: 53 Posts: 4,479	Problem here is that Paula is a strange beast, it's not like the usual PCM or PDM emitter of today. It' a mixed PCM/PWM state machine, prone to distortions due to her inner working. Add to this: specific period granularity, different phase for the channels, different filters, different components, different D/A separations, home made 'software' linear calibration (that any technician would shiver to conceive such 'unreliable' thing )... Many of these properties are not bad per se (far from it!) but they make it difficult to compare it with the existing. Yes, you can measure the 'math quality' of the sound and decide that Paula is 10, 11, 12 bit or alike (I am not among those who think it is even remotely similar to 14 or 16bit). But the 'reconstruction' that Paula do from the discrete quantized bits is pretty unique and not so simply comparable with the existing. What are the conditions that allow it to perform at its best in the 'emulation' of the original signal? I don't think there is anyone here with a precise answer.. So blind test is probably a path to try (as mentioned in a previous message) . But under the conditions of the first post Thomas is right.