Arcam rBlink Bluetooth D/A processor JA on Sound Quality
Sam Tellig loved the rBlink when he listened to it: "If you're looking for a gift idea, and Mom and Dad have Bluetooth devices, put an Arcam rBlink under the tree. While you're at it, get another for yourself," he wrote. "Highly recommended," he concluded.
I streamed Bluetooth data to the rBlink from my iPad 2 and MacBook Pro. I did some listening to the rBlink's analog outputs. The sound was good rather than great, so for my primary auditioning sessions, the Arcam's coaxial digital output was connected to the ASUS Xonar Essence One Muses Edition (see review elsewhere in this issue); I also connected my MacBook Pro's TosLink digital output to the Xonar DAC so that I could compare the Bluetooth versions of the files with the original sent at full resolution to the same DAC via S/PDIF. I connected the Xonar's balanced outputs to the inputs of my HeadRoom BlockHead amplifier, which drove a pair of Audeze LCD-X headphones in balanced mode.
I began my critical listening with Vaughan Williams's Norfolk Rhapsody No.1, performed by Bryden Thomson conducting the LSO (ALAC file ripped from CD, Musical Heritage Society MHS 512595), streamed from my iPad via Bluetooth to the rBlink. The sound was surprisingly enjoyable when the music remained at moderate levels, though the sense of space on this ambient Chandos recording was diminished compared with the same file sent from my MacBook Pro via TosLink to the Xonar DAC. However, there was a feeling of congestion at orchestral climaxes, accompanied by a coarsening of the treble.
Streamed from the iPad, George Benson's cover of "Nature Boy" (a 256kbps AAC file) sounded somewhat brash and compressed, again compared with the same file sent via TosLink to the DAC. The bass guitar also sounded warmer yet better defined with the S/PDIF connection. On the other hand, Elton John and the late Leslie Duncan's "Love Song," from Elton's Chronicles album, also in a 256kbps AAC file, fared better than the Benson track when streamed from iPad to rBlink, sounding less coarse.
Changing to this song streamed from my MacBook Pro, which can use the aptX codec, brought a more natural tonality to the voices, an easier-on-the-ear quality when Elton and Leslie layer the multitracked harmonies, even though there were now two dissimilar codecs being cascaded. Benson's voice in "Nature Boy" also sounded more natural with aptX, though the sense of pace in this track seemed a bit diminished, the sound less vibrant, compared with the TosLink connection to the DAC. Overall, Norfolk Rhapsody 1 sounded closer to the S/PDIF connection from the MacBook Pro than from the iPad, though I couldn't escape the feeling that it was now a little uninvolving overall, sounding softened compared with both the iPad- and TosLink-sourced data.
These comparisons are very demanding, hence fatiguing, especially when using the very revealing Audeze headphones. They are also a great way to destroy any pleasure in listening to music you love. So once they were over, I used the rBlink for the rest of the day's music playback in my main system (see my review of the Xonar Essence One for details) while I got on with magazine work. I connected the Arcam's S/PDIF output to the Auralic Vega DAC I reviewed last month and asked the iPad, which was logged into our domestic WiFi network, to stream me some classical music from iTunes via Bluetooth.
Well, despite my philosophical reservations about lossy codecs in general, and despite my conclusions about the iPad codec in particular from the critical listening sessions, and despite the fact that I'd measured the rBlink before I listened to it, I enjoyed what I heard that afternoon and evening. A stream of Lorraine Hunt Lieberson singing an aria from Handel's Serse, "Ombra Mai Fu," sounded sweet. Nicola Benedetti and the Scottish Chamber Orchestra's recording of Vivaldi's Four Seasons didn't seem lacking in space or dynamics. Yo-Yo Ma's familiar performance of the first Bach Cello Suite sounded natural, though with perhaps a touch more rosin on his bow than I'm used to from the CD. Even Chris Thile's transcriptions of these Suites for mandolin sounded almost as convincing as they had in the hi-rez files I'd purchased from HDtracks. Almost.
Perhaps, because I was streaming classical music, there was more quality to begin with. Perhaps non-classical recordings would be more sensitive to the lossy compression. So I selected "iTunes Weekly Top 50Alternative" on the iPad. Simple, spacious mixes, such as "Royals," from Lorde's Pure Heroine, didn't seem to suffer too much, though "Team," from the same album, sounded grainy and uninvolving, and "Sail," from AWOL Nation's Megalithic Symphony, was simply unlistenable. But both Lorde tracks sounded cleaner via iTunes and the rBlink than they did streaming from YouTube via TosLink to the Xonar DAC.
Could I have been wrong about Bluetooth audio?
"Am I the only one who values content and convenience over sound quality?" asked Sam Tellig in last December's "Sam's Space." He continued, "I love Internet radio via Bluetooth. So much content. So convenient, via smartphone or laptop."
In the past, I've been skeptical about Bluetooth audio, feeling that the possible sonic compromises of the necessary lossy codec outweigh the convenience, other than when it made something possible that would otherwise be impossiblesuch as listening to a live concert from the UK's BBC 3 via the Internet. Arcam's inexpensive rBlink has forced me to reconsider that position. No, Bluetooth audio still doesn't reach CD quality. But it was surprisingly listenable for much of the music I heard while auditioning the rBlink.
Sam was right. Plug the Arcam's S/PDIF output into your high-end D/A processor and you have a convenient and legitimate source of music.John Atkinson