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Old 12-20-2014, 04:32 PM
Crion Crion is offline
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Quote:
Originally Posted by Bob Stuart (with permission)
The graph in the background is an information plot (Shannon diagram). One thing it shows is that the peak information content of the music is about 1/6 of the 4.6Mbps single channel capacity at 192/24.

That fact speaks to efficiency, not to quality improvement. It illustrates that the channel moves much more 'data' than '(relevant) information'. Resolving that conundrum is a matter of lossless compression, which MQA achieves between encoder and decoder.

The headline to emphasise the result is not about efficiency, it's about the system end-to-end (i.e. analogue-through-digital-through-analogue) temporal blur or time-smear.

The inset upper right shows the impulse response of the entire chain (not just a converter), comparing MQA to a high-performance studio ADC/DAC at 192/24 delivering the output of a microphone feed. We can quantify this in a number of ways:
  • Uncertainty of leading edge: MQA = 4us compared to 250us
  • Total impulse duration: MQA = 50us compared to 500us
  • MQA has no post-ring
  • Perceptual smear (relating to the perceived envelope and loudness) MQA at under 10us is at least 10x better.
This is a quality improvement in temporal resolution; the headline of 10x is conservative and we hear the result.

And it can be transmitted at a lower data rate, but that's efficiency gain in part from the end-end nature of the coding and the other innovations.

The problem comes if the graph is taken out of context without the words I was using the the time.

Bob
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