Qvortrup, who often zigs while others zag, helms Audio Note UK. It is a company focused on creating innately musical hi-fi hardware – like the CD4.1x integrated transport and DAC reviewed today – with an emphasis on sounding better rather than necessarily measuring better. A fact echoed in the 4.1x owner’s manual, which declares that it “has been specifically engineered for sonic performance rather than technical specification.” Looking at their product history, the company delivers designs with longevity built-in. Rejecting “upgrade-itis” and seemingly immune from rapid development cycles gripping many hi-fi companies, Audio Note UK constantly examines small refinements to products via materials or parts and new models tend to be an entirely higher-specification or “Level” upwards. The CD5.1x, for example, with output transformers borrowed from the DAC3.1x Balanced, only superseded the CD4.1x as the company’s top-tier one-box transport/DAC in late 2019 – 12 years after the 4.1x was brought to market. Many of the company’s designs are well into their third decade on the books.
Audio Note UK is based in West Sussex, England, a pastoral oil painting away from the southern coastline of Brighton. In reviewing the 4.1x it is difficult to separate the company from the man, because in many ways it is Qvortrup who is the company. He likes to reference Max Planck, Sir John Glubb or other notable, late 19th-century political or scientific figures as casually as others reference weather forecasts. Knowing Qvortrup, one would say he is a man of unparalleled depth, but when it comes to digital playback, his preference is 16-bits of it.
I bring this up because Qvortrup and his chief engineers are more than confident in the adequacy of audio information embedded in the micro-pitted surface beneath a compact disc’s reflective coating. What of DSD or 24-bit/192kHz recordings? Find another company’s DAC to process them because, like the CD4.1x, even the highest-specified, Level Five DAC built by Audio Note UK is designed around the NOS (new old stock) Analogue Devices AD1865N dual D/A converter which speaks in 18-bit word length.
While the Analogue Devices converter used could elicit wonder in this age of Sigma-Delta domination (be it known that multi-bit ladder DACs are known for their natural sound), the rest of the signal path is no less revelatory, highlighting Audio Note’s engineering expertise. Qvortrup and Co. apply a careful selection of materials, along with in-house designed and built components, to breathe life into the sound-first architecture of their circuit designs. Whether it is the transformers used in the current-to-voltage section, the analog output stage with twin dual-triode 6922 valves (which I replaced with mid-‘60s Amperex ‘Bugle Boy’ ECC88s – more on that later), the separate power supplies and mains transformers (one each for the DAC and transport boards), or the fastidious point-to-point wiring and solder joins, the attention to detail involved in the composition and layout of the internal circuitry of the 4.1x is impressive.
The player’s enclosure features either a solid aluminum alloy or black acrylic fascia fronting an internally-sectioned, cold-rolled alloy chassis. It is classified as fulfilling “Audio Note Level Three” criteria for circuit design, quality of components and materials. It houses the foundational elements of the company’s half-width chassis CDT Two/II transport and DAC2.1x, but is upwardly mobile from there with higher-specified components and signal-path ancillaries. These include the broadcast quality, top-loading, Philips CD-Pro2LF transport with magnetic puck clamp and integral four-spring suspension, the liberal use of Audio Note Tantalum resistors and NOS Black Gate signal capacitors, Audio Note copper-foil-in-oil output capacitors, and Audio Note AN-Vx silver interconnect cable for the digital out.
"... we simply do not care about the commercial aspects of what the market “wants” or what other manufacturers say ..."
–Peter Qvortrup, Audio Note UK
The 4.1x utilises no over sampling, no jitter reduction, no noise shaping and no re-clocking. According to the company, “having removed all of the digital filtering that is required for over sampling, all filtering is done in the analogue domain where it is easier to retain good, wide band phase-frequency and dynamically coherent behaviour.” It is in those previously mentioned analogue-domain approaches to performance enhancement that one feels contribute to the astonishingly vinyl-like output of the 4.1x. A vinyl-like output committed, paradoxically, to the medium that caused so many to abandon vinyl to begin with. And the medium which has been abandoned of late by high fidelity manufacturers in favour of dematerialised music. While vinyl has dramatically increased in value after being left behind, the value of the CD has fortunately not. Used CDs can be had for as little as $2~$5 at most record shops. A far cry from Ludwig-mastered Zeppelin pressings and a boon to any growing silver disc collection. While it still remains unclear if one can recoup the $40 paid for 24-bit/96kHz downloads of Mahler, many are backing up their hard drives in hope.
On this subject, Audio Note UK nomenclature is explicit: “Whilst the rest of the audiophile world continues it delusional and ultimately doomed love affair with the currently fashionable crop of what are claimed to be 'high resolution' computer sources, we at Audio Note (UK) continue to extract even greater degrees of information and quality from Red Book CD, which is still the best, currently available digital music format.”
Like the mass exodus from vinyl to polycarbonate in the ’80s with the introduction of the compact disc, the irony of a new generation eschewing CDs for streaming music cannot be lost on cloud-based music skeptics. The difference this time is there’s nothing on the shelf if the Internet music stops. With the growing migration to Spotify, TIDAL, Qobuz, etc., the bulk of the industry has followed with hardware and software solutions. In high-fidelity comparisons Audio Note is in limited company, this is doubly true when it comes to brands, like it, which have not produced a digital-music player or streamer. Audio Note UK continues to only build stepped levels of the one-box CD transport/DAC along with standalone CD transports and DACs. It is only with the company’s new integrated amplifier/DAC – Cobra – that it has deigned to even include an USB input.
I reached out to Qvortrup about his lack of interest in players/streamers, about Red Book as a viable format and why corporeal collections matter in a world obsessed with the dematerialized.
His reply: “Streamers? Here is the short version: In order for us to market a source like a streamer it would have to represent an improvement, or at the very least be comparable sonically, to a decent CD transport (read here one of ours). It is entirely possible to make a streamer that is as good as a lot of the CD-ROM based CD transports from other manufacturers. So far no streamer, regardless of price, that we have compared comes anywhere close to even the lower level CD transports we make. So, as far as we are concerned there is no point in offering a product or group of products that are not an improvement to a similarly priced alternative.
“As you know only too well, we simply do not care about the commercial aspects of what the market “wants” or what other manufacturers say (who all talk rubbish in support of their endless attempts to convince their customers that new is always better). More convenient just does not cut the grade in our world.
“Red Book? Well, first of all there are several trillion CDs already in circulation, so this idea that the compact disc is “finished” is just a load of BS. This whole argument between new and old formats misses this point completely. Just look at the resurgence of vinyl and the increase in value of much of the vinyl catalogue, even third or fourth generation re-releases. There is a lot of wishful thinking here made by people and companies who really have no other ideas than chasing the market with new technology “products.” Regardless of whether these offer consumers something better and more worthwhile or not. All in the vain belief that there lies the next source of riches, much like the home theatre “revolution” 30 years ago. Compact discs will continue to sell in large numbers no matter what the hi-fi industry and its courtiers in the press espouse.”
In everyday use the 4.1x is an attractive top-loading, one-box CD transport/DAC housed in a full-sized Audio Note chassis. The fascia has a large, easy-to-read LED screen below which reside five small buttons to control the transport or dim/shutoff the readout (a plastic remote control is also included). The rear of the unit contains only an IEC mains socket, single-ended outputs and a SPDif digital out for an external DAC. The 4.1x excels at translating sonic tangibles like timbral and tonal delicacy, pitch accuracy and lifelike scale fitting hand-in-glove with dynamic impact and an enormous, rock solid sound stage. In this output the company also commits to less quantifiable sonic properties like emotional heft and living presence resulting in startling amounts of realism from Red Book playback. When directly contrasted against 24-bit/96kHz files played through a Linn Klimax DSM on hand, the 4.1x provided, among its many other sonic attributes, highly-competitive resolution.
The CD4.1x was routed through an Audio Note Oto Phono SE Signature integrated amplifier (10 watts, EL84 output tubes, ECC82/ECC83 line stage) driving Audio Note AN-E SPe/HE loudspeakers (97.5 dB). Cabling consisted of Audio Note Lexus RCA (copper wired, AN-P terminated), Audio Note Lexus bi-wired copper speaker cables, and Audio Note ISIS copper AC/mains cables. The 4.1x was plugged into a Shindo Mr. T power conditioner. As mentioned earlier, the 4.1x features two dual-triode 6922 valves in its analog output. Rolling-in a pair of mid-‘60s Amperex Heerlen factory ‘Bugle Boy’ ECC88s to gauge their impact on performance vs. the stock Russian-branded Electro Harmonix valves was unavoidable. The Amperex revealed more nuanced timbral and tonal shadings to wood-bodied instruments like cello, violin, bass and guitar, as well as more space and tensile purity of bloom on high hat/cymbal shimmer and decay. Ditto, extended reach of percussive slam between the lower octaves. After several weeks of becoming acquainted with this output, Audio Note AN-V RCA (silver wired, AN GP-AG terminated) replaced the Lexus. This final change delivered unsubtle improvements across-the-board in everything previously mentioned with a truly impressive increase in transparency to the upper treble region, along with further bass extension, weight and impact, making the AN-V a logical upgrade for those inclined to wrest the best performance from a source. On this subject, Qvortrup emailed to say the company is “doing a general sweep of much of the product range at the moment to incorporate the latest parts, mainly the new Niobium resistors, which if used carefully in combination with Tantalum and the KAISEI electrolytic caps raise the performance enormously.”
Every bristle of Philly Joe Jones languid brush work on the skins of “I’m Old Fashioned” off Chet Baker Sings – It Could Happen to You (Riverside RLP-1120, Original Jazz Classics, OJCCD-303-2, CD-reissue, 1987) eases in with micro-dynamic detail and organic texture just as George Morrow drops the first bass note on top of Kenny Drew’s halting piano at the 40-second mark and puts all the players on the rug in front of you. Either this track is pitch-perfect, sounding exactly as it should – gripping the listener, leaving one leaning forward and hanging on every note as Baker breathily emotes just behind the beat – or it’s off in timbre, tone and timing and the illusion remains just that. It all depends on your source and the recording, as other releases have disappointed. The 2010 CD reissue, for example, is not nearly as present as the ’87 disc, which the CD4.1x nails with rhythmic drive, projection and spatial sense of the recorded space of this August, 1958 session at Reeves Sound Studios in New York City. The distance from the main mic to Drew on piano is easily defined to the left and back about 10 feet from Baker’s voice and trumpet which projects centre and foreground to Jones’ drum kit. Morrow is slightly back and right in the mix and the whole affair punches with the weight of a roll of quarters tucked into a swinging fist from between the speakers.
One microphone, one guitar, and mistakes. This is how Pat Metheny describes his solo outing One Quiet Night (Warner Bros. Records, CDW 48473, 2003). Most of which, almost unbelievably, was recorded at his home studio over the course of just one day in 2001. From the start of the album there is a sense of communicative struggle from Metheny. Struggle to seemingly bend the guitar to his will, struggle in said guitar’s unwillingness to be bent. Ultimately, the listener comes away sensing both meet halfway, each acknowledging the other’s part in the musical relationship. Deftly stitching together jazz, folk and pop balladry, the tracks segue seamlessly and the entire recording generates a sense of forceful human touch to its presence. In this reviewer's experience, it is this ability to immediately engage the listener emotionally, with corporeal intonation, that sets the best source components apart, and this the CD4.1x did with seeming nonchalance. A guitar laid bare, one's eyes closed, the 4.1x navigates the textural terrain of songs leading to, in some moments, a suspension of disbelief that Metheny is not in the room. Not only is the Audio Note player exceptional at reproducing subtleties of harmonic bloom and decay off guitar strings (along with a convincing portrait of the guitar body's physical mass), but the natural, unforced dynamics of Metheny's chord progressions and harmonies convey an inexorable momentum that carries along the entire album. There is a sense of fine – almost temporal – shading to the spectrum of timbral and tonal colour that Metheny’s haptic playing is capable of producing – with tremendous speed of attack on leading edges of notes – which make hearing One Quiet Night less s a passive listening experience and more an out of body one.
Deep, throaty-rumbling and bouncy electronic bass, taut pizzicato acoustic-plucked bass, driver excursion sub-bass… these are some of the many bass expressions which best showcase a digital source’s ability to impress amongst the lowest octaves. Vienna-based electronica and trip hop downtempo jazz-rockers Peter Kruder & Richard Dorfmeister deliver many bass goods on thier 1998 two-disc set The K&D Sessions (!K7/G-Stone Recordings, !K7073CD, 1998, 2xCD compilation). The albums contain enough j-blunted basslines to keep diehard dub worshippers seated for hours. With 21 tracks of mixes (and two original cuts) containing reworks of artists from Bomb the Bass, Count Basic, and Depeche Mode to Lamb and Roni Size, both Kruder and Dorfmeister brought gifted hands to the muscular and atmospheric mastering of the album which the duo said required two weeks per track. Being aware of the way Audio Note AN-E loudspeakers (based on Peter Snell’s designs) load a room is key to appreciating just how realistically the 4.1x plumbs bass depths. AN-E placement – jammed into corners – creates natural and realistic bass reproduction because it is not exclusively relying on the pistonic air movement of a driver in conjunction with cabinet volume. It’s utilizing the room boundaries themselves for reinforcement – just as a cello, drum kit or piano would. In leveraging this harmonic assistance they provide the 4.1x with ample surface area to fortify lower-bandwidth signal transference. Not only does acoustic, or electronically-augmented/created bass of the K&D Sessions sound startlingly powerful, it pressurizes the room so efficiently that much like a live venue, bass is felt throughout the body as well as via the inner ear. Don’t let the electronic/dub genre-slot fool you, these two discs contain audiophile-exquisite tone and timbre to instruments and vocals with sublime production/sound-staging throughout.
Measurements, like specifications, can only be chapters in the book of how a high-fidelity component’s playback is shaped. Understanding this makes it easy to accept the “…specifically engineered for sonic performance rather than technical specification…” approach Audio Note UK has chosen in designing and building the CD4.1x. Pursuing an ever more realistic reproduction of a resined horsehair bow sliding over catgut strings is, to this reviewer, a more noble pursuit than pursuing ever more vanishing levels of distortion. In the final analysis, a design which satisfies criteria deemed important by the listener must be considered successful. If consistently delivering living presence from recordings, unravelling complex musical structures effortlessly, an ability to evince deep soundstage projection of vocals and instruments with life-size scale, physical, textural heft to notes, emotional and intellectual provocation, unwavering pitch control and authentic colour reproduction to tone and timbre are yardsticks used to measure satisfaction in a compact disc player, then the Audio Note CD4.1x is an incontrovertible success. Whether it was Southern-tinged echoes of pedal steel guitar off "Long Lonely Road" by Valerie June, or the dark speed and power of Crystal Castles' "XXZXCUZX ME," the CD4.1x adapted without pause, shrift or question to whatever was played through it. Other metrics for CD players? There certainly are a lot, but if one’s pursuit is to enjoy music first, and worry about how that is achieved second, then arrange a listening session post haste.