All that glitters is not gold(en)

Recently a video/blog surfaced that claims to show defects in MQA. It does not. This video is based on a flawed test that delivered invalid results. Here we show you why it is wrong.

What follows is a summary response and commentary – backed up by technical analysis appendices.

Responses to Specific Claims

MQA did not delete his files; that accusation is false. MQA is not a rights holder nor distributor. We do not issue takedown notices to distributors or DSPs.
MQA has never made false claims about ‘losslessness’. MQA has been clear from the outset that our process operates in a wider frame of reference that includes the whole chain including A/D and D/A converters. [1]
Provenance: MQA files are delivered losslessly and reconstruct exactly the sound that an artist, studio or label approves.
The blogger’s test failed because he submitted signals that do not resemble music to an encoder that was configured only for music works. Nonsense comes out. This is like being disappointed when a F1 car struggles on an off-road race.
He submitted high-rate composite files containing unsafe levels of ultrasonic signals –in places 100 times higher than in music recordings – resulting in 10x encoder overload. (See Appendix 2)
System error messages generated by the MQA encoder were ignored. [2]
MQA provided detailed feedback to the blogger before publication. [3] He ignored it and later dismissed our detailed guidance as ‘marketing’.
MQA does not add distortion and by design, does not introduce detectable aliasing. (See Appendix 4)
MQA is different from regular PCM for important reasons to do with sound quality. Compared to regular PCM, MQA can deliver higher temporal resolution and lower blur while using less data in delivery.
An MQA encoder can encode any signal that fits in a PCM file, but it is highly optimised for files containing information that is meaningful to human listeners. (To understand the differences see Appendices 3 & 4)
Finally, the title of the video is illogical. [4]

General comment:

The blogger displayed a lack of integrity, violating agreements and Terms of Use with multiple parties within the chain. He claimed to be unbiased, yet from the outset, the narrative pursued an agenda – a libellous manifesto that was unscientific, illogical and inaccurate.

He hadn’t researched how MQA works and padded the video with a litany of alternative facts previously debunked many times by MQA and others.

This is not the first time that people have leveraged MQA to gain ‘clicks’, it won’t be the last.

What follows is an analysis: Appendix 1: A ‘Tarnished Test Signal’

Footnotes

[1] Read more about MQA and losslessness on AES Soundboard, in Stereophile Q&A , and in our AES Hierarchical paper.

[2] This simply does not happen in the normal professional supply chain where the MQA encoder analysis is monitored and highly valued for the forensic QA check.

[3] Our complete response can be found here https://bit.ly/3e3yYF3

[4] FLAC is a lossless file format, a container for audio data. MQA is an advanced method for coding audio contents. MQA is normally delivered (losslessly) in a FLAC container from the music label. PCM is another type of audio that can be delivered by FLAC. Suggesting FLAC is better than MQA is like saying ‘bottles are better than wine’!