Home Digital Drive

Upsamplers, DACs, jitter, shakes and analogue withdrawals, this is it.

There's no free lunch

The fundamental premise of MQA is to reduce the file size of a high-res file. To date the very best *lossless* way to do this was developed by Michael Gerzon in the 1990s, and his predictive algorithms forms the basis for all lossless compression schemes (eg, FLAC, ALAC, Dolby True-HD, MLP, Shorten, et cetera). Of these FLAC is the most commonly used and is considered the best overall optimization of these. None of them have a distinct advantage in terms of the overall file size after compression.

MQA reduces the files size by using lossy techniques. Specifically the least significant bits in the audio band of a PCM file are replaced by a compressed version of the ultrasonic audio data, resulting in a trade-off between bandwidth and resolution (no free lunch).

When starting with a 24-bit container, this may make sense in some circumstances. For example an original 96/24 file can be "folded" into a 48/24 container. Undecoded playback is at 48/17, while decoded playback is "unfolded" as a 96/17 file. It is up to the customer to decide if this is a step forward or a step backward.

However Redbook CD is limited to 16-bit containers. My understanding is that a decoded MQA CD would yield 88/13 playback, and undecoded would yield 44/13 playback. Again, it is up to the customer to decide if this is a step forward or a step backward.

As always, my posts reflect my personal opinions and not necessarily those of my employer or friends.

This post is made possible by the generous support of people like you and our sponsors:
  Parts Connexion  

Follow Ups Full Thread
Follow Ups


Post a Message!

Forgot Password?
Moniker (Username):
Password (Optional):
  Remember my Moniker & Password  (What's this?)    Eat Me
E-Mail (Optional):
Message:   (Posts are subject to Content Rules)
Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:  Automagically notify you when someone responds.