I haven't heard the album in question. Assuming it is a white-glove mastering, I would expect most or all of the following to be in place on a 44k original recording:

1) compensation for the characteristics of the ADCs, which in this case would definitely be known.
2) upsampling (i.e. to 352kHz) using apodising to remove blurring.
3) encapsulating of the deblurred file as MQA (back down to 44kHz).
4) matching to the DAC as part of the MQA decoding process.

Note that no. 2 being done offline, doesn't have any of the processing limitations of hardware upsampling.

None of this is anything to do with MQA simply encoding high-res audio.

And if it sounds great what's the problem? wink

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