Tag Archives: mqa

audio, gadgets, hifi

Audirvana Plus for Windows review: a music player which combines convenience and no-compromise audio

Audirvana Plus, an audiophile music player for the Mac, has now been released for Windows.

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Audirvana was developed in France by Damien Plisson, originally as an open source project (you can still get this here but it has not been updated since 2012). The description there still applies: “No equalizer, no trendy special effects, just the music”.  Both Mac and Windows come with music players bundled with the operating system – in Apple’s case the mighty iTunes – but the issue which Audirvana addresses is that these players are about convenience and features as well as sound quality.

Another problem is that the sound system in a modern operating system is complex and needs to support every kind of application while from the user’s perspective it should “just work”; and this can mean compromises, such as resampling or normalizing the audio. This does not matter in most circumstances, but if you want the best possible sound and spend money on high-res downloads or streaming, for example, you want bit-perfect sound.

This perhaps is a good reason not to play music directly from a PC or Mac; but the counter-argument is that using your existing computer reduces the box-count (and expense) of streaming, and that the flexibility and processing power of desktop computer is handy too.

So what does Audirvana offer? The Windows version is still to some extent work in progress and not yet as full-featured as the Mac version; however the developers are promising to add the missing pieces later. However the product is already a capable player with the following key features:

1. Wide range of supported formats including AIFF, WAVE, AAC, MP3, FLAC, Monkey Audio APE, WavPack, Apple Lossless, DSD (DSDIFF including DST compressed, DSF, and SACD ISO images).

DSD support works whether or not you have a DSD DAC. If you have a DSD DAC, you get full native DSD. If you do not, Audirvana will convert to hi-res PCM and it still sounds good. You can control how the DSD is converted in settings, such as the amount of gain to apply (without it, DSD files will sound quiet).

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Here is a DSD file playing on a non-DSD DAC:

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2. MQA unfolding whether or not you have an MQA DAC. The way this works is similar to DSD. If you have an MQA DAC, the decoding will take place in hardware. If you do not, Audirvana will process the MQA track in software. For example, I have a 16-bit, 44.1 kHz MQA-encoded FLAC that plays in Foobar 2000 as a 16/44 file, downloaded from here. In Audirvana though, the same file claims to be 24-bit/352.8 kHz track.

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That resolution is not  genuine; but what matters is that MQA decoding is taking place. If the file is played through an MQA-capable DAC like the Meridian Explorer 2, I get a green light indicating MQA decoding on the DAC. If I play the “original resolution” version, I get a blue light indicating “MQA Studio”. WASAPI and ASIO support. WASAPI is the native Windows standard which enables bit-perfect output and is aimed at professional audio engineers. ASIO is a standard with similar features developed by Steinberg.

3. A library manager which performs well with large numbers of tracks. I tried it with over 50,000 tracks and it was perfectly responsive. It uses the open source SQLITE database manager.

4. Hi-res streaming via Qobuz, HIRESAUDIO or Tidal. There is no support for the likes of Spotify or Apple Music; I guess these are not the target market because they use lossy compression.

Not available yet, but coming, is a remote app for iOS (iPhone, iPad and iPod Touch), audio effects via VST plugins, and kernel streaming output.

The Audirvana User Interface

Audirvana is delivered as a download though it is a click-once application which means it updates semi-automatically, prompting you to update if an update is available. The user interface is, from the point of view of a Windows user, rather quirky. There is no menu or ribbon, but by clicking around you can find what you need. Some of the settings are accessed by clicking a gearwheel icon, others (such as the per-device options shown in the illustration above) by clicking an arrow to the right of the device name. There is also a compact view, obtained by clicking a symbol at top left, designed for playback once you have lined up the tracks you want.

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The current version seems unreliable when it comes to showing cover art in the library. Sometimes cover art shows up in the mini view, but not the full view.

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Searching the library is quick, but because the user interface is fairly blocky, you do not see many results on a page. An option just to show details in a list would be good (or perhaps it exists but I have not clicked in the right place yet).

I can forgive all this since despite a few annoyances the user interface is responsive, the search fast, and playback itself works well.

Sound quality

How much impact does the music player have on sound quality? This is difficult to answer definitively. On the one hand, the amount of distortion introduced by a sub-optimal player should be negligible compared to other sources of distortion. On the other hand, if you have gone to the trouble and expense of investing in hi-res downloads, streaming or DSD, it must be worth ensuring that every link in the chain does justice to those sources.

It is true that on Windows, with its enthusiastic technical audiophile community, most of what Audirvana does can be achieved with free players such as Foobar 2000 or VLC. There is also the excellent JRiver as an alternative paid-for player, though this lacks software MQA decoding (appreciating that not everyone likes or needs this).

That said, the uncomplicated user interface of Audirvana Plus is great for audio enthusiasts who would rather not spend too much time fiddling with settings or plugins. Support for the iOS remote app is an unfortunate missing piece at present, and Android users miss out too.

The Windows version needs a bit more work then (I also encounted some unpleasant noises when trying to adjust the volume within the application), but it does enough right to justify its relatively modest cost, and the bugs will fixed. Head over to the Audirvana site for a free trial.

audio, hifi

More on MQA and Tidal: a few observations

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I have signed up for a trial of the Tidal subscription service and have been listening to a few of the MQA-encoded albums that are available. You can find a list here. Most of the albums are from Warner, which is in the process of MQA-encoding all of its catalogue.

From my point of view, having familiar material available to test is a huge advantage. Previous MQA samples have all sounded good, but with no point of reference it is hard to draw conclusions about the value of the technology.

I have used both the software decoding available in the Tidal desktop app (running on Windows), and the external Meridian Explorer 2 DAC which is an affordable solution if you want something approaching the full MQA experience.

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Note that on Windows you have to set Exclusive mode for MQA to work correctly. When using an MQA-capable DAC, you should also set Passthrough MQA. The Explorer 2 has a blue light which shows when MQA is on and working.

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For these tests, I used the Talking Heads album Remain in Light, which I know well.

The Tidal master is different from any of my CDs. Here is the song Born under Punches in Adobe Audition (after analogue capture):

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Here is my remastered CD:

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This is pretty ugly; it’s compressed for extra loudness at the expense of dynamic range.

Here is my older CD:

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This is nicely done in terms of dynamic range, which is why some seek out older masterings, despite perhaps using inferior source tapes or ADC.

This image shows three variants of the track streamed by Tidal and captured via ADC into a digital recorder at 24-bit/96 kHz.

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The first is the track with full MQA enabled and decoded by the Explorer 2. The second is the “Hi-Fi” version as delivered by Tidal, essentially CD quality. The third is the “Master” version, in other words the same source as the first, but with Exclusive mode turned off in Tidal, which prevents MQA from working.

You can see at a glance that MQA is doing what it says it does and extending the frequency response. The CD quality output has a maximum frequency response of 22 kHz whereas the MQA output extends this to 48 kHz at least as captured by my 24-bit / 96 kHz (the theoretical maximum frequency response is half the sampling rate).

Do they sound different though, bearing in mind that we cannot hear much above 20 kHz at best, and less than that as we age? I have been round this hi-res loop many times and concluded that for most of us there is not much benefit to hi-res as a delivery format. See here for some tests, for example.

MQA is not just extended frequency response though; it also claims to fix timing issues. However my captured samples are not really MQA; they are the output from MQA after a further ADC step. Of course this is not optimal but the alternative is to capture the digital output, which I am not set up to do.

An interesting question is whether the captured MQA output, after a second ADC/DAC conversion, can easily be distinguished from the direct MQA output. My subjective impression is, maybe. The first 30 seconds of Born Under Punches is a sort of collage of sounds including some vocal whoops, before David Byrne starts singing. What I notice listening to the Tidal stream with MQA enabled is that the different instruments sound more distinct from each other making the music more three-dimensional and dramatic. The vocals sound more natural. It is the best I have heard this track.

That said, I have not yet been able to set up any sort of blind test between the true MQA stream and my copy, which would be interesting, since what I have captured is plain old PCM.

There is a key point to note though, which is that mastering offered by Tidal is better than any of the CD versions I have heard; the old Eighties mastering is more dynamic but sounds harsher to my ears.

With or without MQA; you might want to subscribe to Tidal just to get these superior digital transfers.

Update: it seems that the Tidal stream for Remain in Light (both MQA and Hi-Fi) is a different mix, possibly a fold-down from the 5.1 release. So it is not surprising that it sounds different from the CD. The question of whether the MQA decoded version sounds different still applies though.

audio, hifi, music industry

The MQA enigma: audio breakthrough or another false dawn?

The big news in the audio world currently, announced at CES in Las Vegas, is that music streaming service Tidal has signed up to use MQA (Master Quality Authenticated), under the brand name Tidal Masters. MQA is a technology developed by Bob Stuart of Meridian Audio, based in Cambridge in the UK, though MQA seems to have its own identity despite sharing the same address as Meridian.

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What is MQA? The question is easy but the answer is not. Here is the official short description:

Conventional audio formats discard parts of the sound to keep file size down, but part of this lost detail is the subtle timing information that allows us to build a realistic 3D soundscape in our minds. … With MQA, we go all the way back to the original master recording and capture the missing timing detail. We then use advanced digital processing to deliver it in a form that’s small enough to download or stream.

At first sight it looks like another format for lossless audio, and the description on MQA’s site confuses matters by making a comparison with MP3:

MP3 brings you just 10% of what was recorded in the studio. Everything else is lost to fit the music into a conveniently small file. MQA brings you the missing 90%.

There are two problems with this statement. One is that MP3 (or its successor AAC) actually sounds very close to the original, such that in tests most cannot tell the difference; and the other is that audiophiles tend not to use MP3 anyway, preferring formats like FLAC or ALAC (Apple’s version) which are lossless.

There is more to it than that though. There are three core aspects to MQA:

1. “Audio origami”: MQA achieves higher resolution than CD (16-bit/44.1MHz) by storing extra information in audio files that is otherwise wasted, as it stores audio that is below the noise floor (ie normally inaudible). There is a bit of double-think here as removing unnecessary parts of audio files is the sort of thing that MP3 and AAC do, which the MQA folk have told us is bad because we are not getting 100%.

This is also similar in concept to HDCD (High Definition Compatible Digital), a technology developed by Pacific Microsonics in the Eighties and acquired by Microsoft. Of course MQA says its technology is quite different!

Note that you need an MQA decoder to benefit from this extra resolution, and there is a nagging worry that without it the music will actually sound worse (HDCD has the same issue).

2. Authentication. MQA verifies that the digital stream is not tampered with, for example by audio features that convert or enhance the sound with digital processing. This can be an issue particularly with PCs or Macs where the built-in audio processing will do this by default, unless configured otherwise.

3. Audio “de-blurring”. According to MQA’s team:

There’s a problem with digital – it’s called blurring. Unlike analogue transmission, digital is non-degrading. So we don’t have pops and crackles, but we do have another problem – pre- and post-ringing. When a sound is processed back and forth through a digital converter the time resolution is impaired – causing ‘ringing’ before and after the event. This blurs the sound so we can’t tell exactly where it is in 3D space. MQA reduces this ringing by over 10 times compared to a 24/192 recording.

If this is an issue, it is not a well-known one, at least, not outside the niche of audiophiles and hi-fi vendors who historically have come up with all sorts of theories about improving audio which do not always stand up to scientific scrutiny.

So is MQA solving a non-problem? That’s certainly possible; but I do find it interesting that MQA has received a generally warm reception from listeners.

Here’s one audiophile’s reaction:

Have never really “done” digital before. 16/44 has always sounded ghastly to my ears right from the start and still now. MQA did indeed “fix” the various forms of distortion that I could hear present in everything where the sampling rate was taken down to just 44. … My findings – those of an improved sense of solidity in the stereo image and the lack of that horrendous crystalline glassy edge to things, especially on the fade, seem to be being mirrored in what people are hearing. It doesn’t have that thing I describe as a “choppy sense of truncation” which I suspect others mean by “transients”.
Basically, per the post above, it’s a bit like “good analogue”. Digital can finally hold its head up high against an analog from master-to vinyl performance. And not only that, hopefully, walk all over it and give us something genuinely new.

If this history of audio has shown us anything, it is that subjective judgements about what makes something sound better (and whether it is better) are desperately unreliable. Further, it is often hard to make true comparisons because to do requires so much careful preparation: identical source material, exactly matched volume, and the ability to switch between sources without knowing which is which, to avoid our clever brains from intervening and telling us we are hearing differences which our ears alone cannot detect.

We should be sceptical then; and even possibly depressed at the prospect of a proprietary format spoiling the freedom we have enjoyed since the removal of DRM from most downloadable audio files.

Still … is it possible that MQA has come up with a technology that really does make digital audio better? Of course we should allow for that possibility too.

I have signed up for Tidal’s trial and will report back shortly.