Berkeley Audio Design Alpha DAC Reference Series 2 MQA

Welcome Surprise

Equipment report
Digital-to-analog converters
Berkeley Audio Alpha Reference DAC Series 2
Berkeley Audio Design Alpha DAC Reference Series 2 MQA

“Inspiration exists, but it has to find you working.” Pablo Picasso surely wasn’t referring to designing digital-to-analog converters when he said this, but his insight is as true in engineering as it is in art. “Working” can set you on a path in which inspiration leads to a destination entirely unimaginable beforehand.

Inspiration appears to have found Michael “Pflash” Pflaumer, designer of the Berkeley Audio Design products, as he spent more than 400 hours writing new software that would make the Berkeley Alpha DAC Reference Series 2 compatible with MQA. Not only did he succeed in adding MQA rendering to the DAC, in the process he apparently discovered ways to greatly improve the sound of the Alpha DAC Reference Series 2 when decoding conventional PCM files. In fact, as exciting a development as it is to hear MQA decoded with a state-of-the-art DAC, what this software update does for PCM files is just as astounding. It’s all the more surprising because the Alpha DAC Reference Series 2 was already the best digital I’d heard; to improve its sound as much as this software update does was completely unexpected—and thrilling. (See my reviews in Issues 246 and 266.)

First the nuts and bolts. If you own an Alpha DAC Reference Series, you can update the $595 software for yourself. Berkeley sends you an information package and instructions via FedEx that includes a web address where you can download the new software. Included in the package is a sticker with a unique serial number that you affix to the rear panel. You’ll need this sticker and its serial number for any future warranty repairs. I downloaded the software (which is formatted as a WAV file) to my PC, transferred it to the Aurender W20 music server, and then followed the instructions for putting the Alpha DAC Reference into a special mode that allows the software to be updated. Once in that mode, I “played” the software file from the Aurender as though the software were an audio file, and seconds later the Alpha DAC Reference could render MQA. If you buy a new Alpha DAC Reference Series 2 MQA ($19,995), the latest software is already installed.

With the new software, the Alpha DAC Reference Series 2 MQA isn’t a full MQA decoder. Rather, it is an “MQA renderer” that performs the second stage of MQA decoding. This can be a confusing issue, so I’ve tried to clarify how this works in the accompanying sidebar. In a second sidebar, I explain why Berkeley chose this path, along with eschewing a USB input and network connections.

With about 5000 MQA-encoded albums on Tidal, there was no shortage of source material with which to evaluate the Berkeley. Note that if you select “Masters” on the Aurender Conductor app (“Masters” is how Tidal designates MQA files) you’ll see fewer than 500 of the 5000+ MQA-encoded albums. That’s unfortunate because listeners naturally think that’s the extent of the MQA library. MQA or Tidal should provide a continuously updated database of music available in the MQA format. The music-server company Lumin has created a searchable PDF populated with about 3500 titles, which is how I discovered much of the MQA-encoded music I’ve been enjoying lately. Who knew that Tidal offers in MQA 16 John Coltrane albums, 18 Aretha Franklin titles, 12 Herbie Hancock releases, and the entire catalogs of Led Zeppelin, The Doors, and ELP, to name a few?

One MQA-encoded album that told me volumes about the Berkeley’s sound quality (and about MQA in general) was Steely Dan’s Gaucho. I remember buying this LP the week it was released, and I’ve owned different vinyl pressings, several CD reissues, and an SACD version. Taking just the track “Glamour Profession” as an example, the sound quality of the Berkeley rendering this MQA file left me slack-jawed. As well as I know this album (I studied it as a model of engineering and production when I was an aspiring recording engineer, and have used it as a reviewing tool for decades), I’ve never heard it sound like this. For starters, the Berkeley deconstructed the arrangement into its meticulously crafted elements and presented each of them as individual lines. Don’t think for a second that the word “deconstructed” suggests an analytical character that is the antithesis of musical involvement. Rather than encouraging analytical abstraction, the Berkeley’s ability to separate each instrument or section revealed, with greater clarity and insight, the musical conception.

What specific characteristics of the sound led to this impression of hearing each instrument or section more clearly, and differentiated it from the others? There are three factors. First, the Berkeley rendering the MQA file had a wide timbral palette, portraying instrumental textures with more intense color, tonal saturation, and realism. I heard an increase in resolution of very fine inner detail, the kind of information that conveys the mechanisms by which the sound is created, the materials of the instrument making the sound, and the performer’s technique. This greater density of tone color helped to distinguish each instrument from the others.

Second, and undoubtedly a contributor to the timbral realism just mentioned, I heard a reduction in an artifact that in other digital (including, to some extent, the Alpha DAC Reference Series 2) tends to add to all instruments. This blanket artifact imposed on the sound tends to blur the distinction between tonal colors by adding a “sameness” to each instrument. Although exaggerated for clarity, you could characterize this artifact as a “whitening” of tone color, a glare in the upper-midrange and treble, a hardness of texture, and a congealing of space between instruments. Stripping away this form of distortion allows the harmonic tapestries of each instrument to be more fully expressed and thus differentiated from each other.