The MQA Messaging: Questions

Master Quality Authenticated (MQA) is the latest darling of the audiophile press and (even mainstream) music industry. There are been a number of articles and web posts that go through the technology. Some months ago, I addressed the clever bandwidth reduction techniques that the developers devised to bring large data rates below those of CDs. That’s the core of MQA. It is a methodology of reducing the footprint and transmission pipeline requirements of PCM encoded audio files larger than a compact disc. And it does this without abandoning the legacy formats…it is backwards compatible. If you don’t have an MQA enabled piece of hardware, encoded discs will function at normal resolutions. Brilliant.

It doesn’t alter the fidelity of the original source, which is likely to be an older standard definition analog tape transferred to a high-resolution bit bucket. MQA will allow standard definition recordings that use too much bandwidth to be streamed in smaller packets. That’s a great move forward for getting real high-resolution audio into the streaming world. I’ll be talking about that in my keynote address today at the Newport Show.

Here’s the transcription of the presentation text I peeled from the Meridian video at the recent Munich Show. I think it’s important to parse this communication and do a reality check on some of the points.

“MQA stands for Master Quality Authenticated. It means that in the studio, the artist can be sitting there in the studio with the producer and they can say, “this is my final master, this is my art, this is what I want everyone to hear. In fact, I want them to hear this exact sound. So now you’ve got a master quality file in a convenient, easy to use format that it is authentic and everyone knows. It takes away the arguments that have been going on over and over about the provenance of the files. Where did it come from? Was it upsampled? Is this the one that they really worked on? It now guarantees that you as the music lover, the music fan, are getting the exact file.”

So you’re an artist or producer sitting in the studio (mixing or mastering?) expressing satisfaction at the sound coming from the expensive and tuned monitor speakers. That’s master quality. It is most likely not high-resolution audio because virtually all commercial productions are recorded at 48 kHz/24-bits…AND heavily processed so that the dynamics are almost completely flat. “This is my final master, this is my art, this is what I want everyone to hear.” OK, fine. I call that the “master source”…and so should those pushing the misleading definition of high-resolution audio.

The studio will prepare the final transfer to the formats required by the label…44.1 kHz/16-bit PCM for the CD and 96 kHz/24-bits for “Mastered for iTunes” (which requires a sample rate conversion step). Then the 96 kHz/24-bit master is encoded into MQA from the new PCM transfer…note the new file is full of zeros. There is no data above the Nyquist frequency of the original 48 kHz file.

You can have the PCM original file or the MQA file. Which would your prefer? Maybe you want the upconverted version.

Most new record productions are not being done in high-resolution audio.

The tracks that everyone wants in “high-resolution” are the older analog tapes that will be newly transferred from the analog tapes to new PCM high-res buckets. This should be done using the best analog tape machines, the best electronics, and without any modifications or remastering. This is the archive.

There are some frequencies above 22.050 kHz that can be captured from an analog tape but the dynamic range never rises above 10-12 bits…usually much less. Capturing these new transfers at 96/192 kHz/24-bit PCM with great converters is the right thing to do. If TIDAL or someone else wants to stream these “master quality” files, then MQA makes it possible. The 4000 kbps becomes 1000 kbps for a file that isn’t high-resolution but does sound exactly like the original master.

The arguments about provenance will continue because the master source production sequence is still unknown. There are still no guarantees that you’re getting something better than what we had previously or that the transfer was done from the right “master”. It simply means that you haven’t lost anything in the conversion…AD and DA.

Let’s not elevate the MQA technology to something that it’s not. I applaud Robert and Peter on a remarkable invention. But it’s not going to create “holograms of instrumental sound apart from the hiss and room ambiance”.