CD Player/Transport Reviews

In fact, I found the differences among the three filters greater in degree than with other DACs that offer a choice of filters. The Min filter gave the best balance between presentation of detail and listenability with "Whaling Stories," from Procol Harum's Live: In Concert with the Edmonton Symphony Orchestra (16/44.1 ALAC rip from CD, Mobile Fidelity/A&M). I always felt that drummer B.J. Wilson overplayed—I saw this lineup of the band in concert in England not long after this album was recorded—but the MBL DAC with Min filter prevented him from overpowering both the rest of the band and the orchestra. Alan Cartwright's bass guitar in this live recording has always sounded a bit "plummy," but the MBL DAC retained the leading edges of the instrument's sound.

What about intersample overs? Vince Gill and Paul Franklin's album Bakersfield (16/44.1 ALAC file, MCA Nashville) has been in constant rotation here since its release in 2013, but like so many recordings these days, it has a relentlessly loud quality. "The Fightin' Side of Me" has some intersample overs, but it didn't sound as in-my-face as I'm used to through the MBL's DAC. Was this a benefit of the N31's digital filter headroom? When I played "Gaslighting Abbie," from Steely Dan's Two Against Nature (CD, Giant), it lit up the red clipping LEDs on my 1993-vintage Dorrough digital-input level meter, which I'd hooked up to the N31's AES/EBU output. This happened with the wound-up-tight snare drum. Of course, a clipped snare drum doesn't sound very different from an unclipped snare drum; nevertheless, the N31 with its Min filter gracefully reproduced this overcooked track.

In fact, with older digital recordings, the N31 sounded simply magnificent. I was playing "Southern Cross," from Crosby, Stills & Nash's CSN (4 CDs, 16/44.1; 320kbps AAC file, Atlantic 82319-2). I love the chorus of this song, based as it is on the soul-satisfying 1-4-5, tonic-subdominant-dominant, departure-discovery, return-and-reaffirmation blues progression, but I felt the music wasn't quite matched by the sound quality of the lossy compressed file. But, as before, the N31 allowed sonic shortcomings to step to one side, letting the rock'n'roll magic flow forth. And again, the N31's presentation of detail was superb. The quiet solo guitar in the song's instrumental bridge, for example, stood clear of the multitracked guitars that accompany it in the refrain, but was presented well behind the loudspeakers.

The N31's USB 2 input will work with iDevices running iOS7 and up, using the Lightning-USB adapter from Apple's Camera Connection Kit. I connected both my iPad mini and iPhone 6S, using the CCK and a long Belkin Gold USB cable, and noted that their own volume controls were disabled, allowing full-resolution data to be sent to the N31. Apple's Music app will work for 44.1 and 48kHz files, while an app such as Onkyo's HF Player will allow the N31 to play 24-bit files with sample rates up to 192kHz as well as DSD files. The iPhone and iPad are not sources I routinely use in my listening room, but their sound quality with both the Music and Tidal apps was excellent driving the N31.

A recent discovery on Tidal was Daniel Barenboim and the Staatskapelle Berlin's 2016 performance of Elgar's Symphony 1 (16/44.1, Decca/Tidal HiFi). Facebook recently informed me that Sir Thomas Beecham regarded Elgar's music as "the musical equivalent of St. Pancras Station," but I love both Elgar's wonderful Victorian music and the equally wonderful Victorian architecture of London's St. Pancras, especially now that the station has been renovated. With the Tidal app on my iPad mini streaming this majestically scored symphony to the N31, I could hear no difference between this source and using Tidal on the NAD M50.2 server feeding the same data via S/PDIF to the N31, or using Roon/Tidal on my Mac mini via USB.

Comparisons
I first compared the N31 with the PS Audio PerfectWave DirectStream D/A converter ($6899 with Bridge II network adapter card), which I bought following the publication of Art Dudley's review, in 2014. The DirectStream DAC perhaps sacrifices ultimate resolution in favor of a "comfortable" sound. Compared with the PS Audio, and even after compensating for the PerfectWave's 3.3dB lower level, with the N31 the MBL had a sense of greater drive and impact, especially in the bass. (To make sure the playing field was level, all comparisons were performed with the NHT PVC used to match levels at 1kHz.) Not only was the MBL DAC rather more resolving of recorded detail, there was a feeling of drive in its low frequencies with Bob Silverman's Rachmaninoff recording that made the PS Audio sound too soft.

I then turned to the Ayre QX-5 Twenty ($8950), which I reviewed last August, again with levels matched at 1kHz. (The Ayre's maximum output is 0.7dB hotter than the MBL's.) The Ayre's Listen filter is similar in the time domain to the N31's Min filter, and Silverman's Rachmaninoff sonatas sounded very similar on the two DACs in both tonal quality and soundstage presentation. "Gaslighting Abbie" also sounded similar to how it had through the N31. I don't know how the Ayre's digital filter deals with intersample overs, but if I had to swear on it, that overcooked snare drum did sound slightly less natural through the QX-5 Twenty.

Finally, I compared the N31 with the AVM Ovation MP 8.2 ($10,995), which Art Dudley reviews elsewhere in this issue and which has a maximum output 4.6dB lower than the MBL's. Art called it correctly when he wrote that this German DAC did "an exceptional job of allowing the songs as much flow and momentum, and consequent emotional impact," as he'd heard from an XTC CD. With the Silverman Rachmaninoff CD-R, and with the MP 8.2's filter set to Smooth and 176.4kHz upsampling, the sound of the piano was a little more forward in the midrange, but there was a little less bottom-end weight. The forward midrange was also a factor with CSN's "Southern Cross," with the slight amount of congestion in the backing vocals more audible than it had been with the N31. "Gaslighting Abbie" also sounded more forward than it did through the N31, with a propulsive sense of drive and excellent definition of the bass guitar, but the snare drum did sound a touch more aggressive with the MP 8.2 than with either the MBL or the Ayre.

Overall, I preferred the MBL N31 to the PS Audio and AVM, though with the Ayre it was a close call.

Conclusions
The N31's absence of a volume control might be a problem for those who've sold their preamplifiers, as will be the lack of a network port for those who've banished their noisy NAS drives from the listening room. And I wish that MBL's filters could be selected with the remote. But, as I say in the "Measurements" sidebar, digital audio engineering doesn't get any better —nor, I feel, does digital sound quality. At $15,400 it may be expensive, but MBL's Noble Line N31 is beyond reproach.