What is MQA? Meridian’s digital audio format explained

MQA is a solution to a very ‘now’ problem: in this era of Hi-Res Audio, how can you deliver top-quality lossless sound without zapping everyone’s data allowance or having to buffer constantly on anything but the best connection?

MQA has the potential to become the lead format for the streaming side of the audio revolution that the marketeers hope is about to take place.

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If it's to bring hi-res audio to the masses, where will we able to get MQA? Well the big deal is that Meridian Audio has partnered with 7Digital.

Some of you will have heard of this company, some will not, but it's what provides several of the smaller streaming services with audio. These include Tidal, Pure, HMV Digital and Technics Tracks. No, not Spotify or Deezer. But we're expecting more partnerships to be announced this year.

However, don’t expect all your future streams from Tidal and the like to use MQA. It’s only really designed to transmit very high-quality streams, with standard FLAC or ALAC (its Apple equivalent) still very much relevant for lossless CD-quality audio.

It’s when we leap from 44.1KHz, 16-bit to 192KHz, 24-bit-grade audio that MQA comes into its own. “There is no fixed date to start MQA streaming by Tidal,” we were told by a spokesperson, but it is certainly on the way.

If your setup can handle those sorts of streams you should also not (in theory) need any new hardware. MQA isn't a brand-new way of encoding audio data, but rather a novel way of packing up music files.

How does MQA work?

It doesn’t demand a whole new order of audio hardware.

Instead, MQA is a way to pack up raw PCM audio data before it reaches that stage. To really understand it, we have to start at the basics.

Going from analogue music to digital is basically a process of reducing sound to a number of snapshots per second, a bit like the frames that make up a film. With ‘CD quality’ 44.1KHz, you get 44,100 of these snapshots per second, and with Hi-Res audio you get significantly more, often with 96,000 or even 192,000.

One of the core ideas behind MQA is that more than one snaphot’s worth of data can actually be crammed into each snapshot, because of how little of the thing is actually used up by data relevant to the music being represented. Think of it as a notepad page with excessively large margins, if that helps. Stereophile editor John Atkinson uses an origami metaphor, the idea of folding a sampling rate in on itself: whatever works.

This allows MQA to represent the data from a 192KHz stream folded into a 96KHz file, radically reducing the size of Hi-Res audio.

At present there are two quality rates of MQA talked about, a ‘download’ quality that uses about 3Mbps for a stereo feed and a ‘stream’ quality that requires uses 2Mbps, each representing a different sampling rate. ‘True’ high-res uncompressed 24-bit, 192KHz audio uses up just over 9Mbps. There’s a huge difference, and streaming raw lossless audio over a mobile internet connection just isn’t feasible at present.

One very neat element of MQA is that even hardware that does not specifically support it will be able to 'decode' 44.1KHz, 16-bit audio from it.

Here’s the biggie: should you care? Does it matter? From a technical perspective MQA is very interesting, but as with anything to do with the current Hi-Res Audio, needs to be viewed in the right context. And that is not something Meridian Audio currently supplies.

Is streaming really the nadir of audio quality? Absolutely not. Even Spotify, which doesn’t bang on about how high-quality its streams are, offers a quality option that, for most equipment and ears, will be indistinguishable from lossless audio.

It’s easy for some people to get audio OCD over bit depths and sampling rates, but remember: it’s all pointless if your ears can’t tell the difference. So make sure you put them to the test with some demos before spending too much money, or time, on getting your home setup MQA-ready.

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