Audio Note CD-4.1x CD player

For a manufacturer to squeeze money from the stone that is my CD-player budget, his products would have to be both exceptional and affordable. And as long as I'm reporting from Fantasyland, I'll ask that they also be obsolescence-proof.

That last goal, especially, is one most designers try to reach by adopting ever-new technologies: new digital-to-analog converters, new filters, new numbers. But there remain a handful of manufacturers who would win the numbers game by not playing it at all, Audio Note UK among them. Not that the British firm is against progress per se—but as far as their digital playback gear is concerned, theirs is a decidedly different approach. Their digital credo might best be summed up as: The key to making products that sound more analog is not to be found in the world of digital. Or, putting it another way: Don't bring a chip to a transformer fight.

The latest embodiment of this policy is Audio Note's new flagship CD player, the CD-4.1x ($12,000), a top-loading, single-box product that the company says combines its CDT-Two/II transport ($7450) with a slightly upgraded version of its DAC 2.1x ($4200).

Among the many keen descriptions in Terry Pratchett and Neil Gaiman's comic novel Good Omens, one stands out. Writing about a character's odd choice of automobile, the authors observe that "It was state of the art, [but] the art in this case was probably pottery." That quote came to mind more than once while living with the CD-4.1x, but not in a pejorative sense—not at all, in fact.

Famously—in audiophile circles, at least—Audio Note rejects the use of oversampling digital filters, and promotes their CD players and D/A converters as "1x oversampling" products. According to managing director Peter Qvortrup, "Oversampling is the digital equivalent of feedback, and it causes a colossal amount of damage. All we can really do is to minimize the damage being done in the digital domain." He added that products without digital filtering "will have more of the qualities you associate with analog. Not all of them, mind you—but more."

The Audio Note CD-4.1x uses no filtering at all, digital or analog: Instead, the player takes advantage of the natural rolloff provided by the transformer coupling in its current-to-voltage section, a design for which AN has received patents in the US, UK, and Australia.

The new player's I/V section is driven by the Analog Devices AD1865N chip: a dual D/A converter with an 18-bit word length. "We've done comparisons," Qvortrup said, "and I consider the AD to be the best-sounding converter, by far." The AD1865N is also used in other of Audio Note's upmarket digital products, and Qvortrup says the company recently bought 1000 of the chips: a wise investment, as Analog Devices no longer manufactures it.

The transport mechanism selected for the CD-4.1x is more current: the Philips CD-Pro2LF, a decidedly robust drive that's engineered specifically for the broadcast and perfectionist-audio markets. The Philips uses a magnetic disc clamp—in the CD-4.1x's case supplied as a removable puck—and an integral four-spring suspension. With regard to product longevity, Audio Note has yet to buy-in as many spare samples of the CD-Pro2LF as they have the AD1865N chip, but, Qvortrup said, "I've gotten Philips to guarantee me that they will give me a minimum three years' notice when they plan to discontinue the Pro." (He pointed out that, with regard to the Philips L1210 transport used in Audio Note's less expensive players and transports, AN purchased the company's last stock: some 4000 units.)

All of the above are implemented in ways that will be familiar to longtime Audio Note enthusiasts. The analog output section is built around a stereo pair of 6H23N dual-triode tubes—a Russian substitute for the more common 6922—configured as anode followers. The nicely made can-style transformers used in the I/V section appear similar to the ones Audio Note makes for their phono transformers. Expensive tantalum resistors are used throughout—more so in this integrated player than in the standalone version of its D/A converter, I'm told—while most of the capacitors are Cerafine granulated ceramic types. Output capacitors are Audio Note copper-foil-in-oil types, while the digital-out cable is a length of the company's own AN-Vx shielded silver interconnect. Separate power supplies, with separate mains transformers, are used for the transport and DAC boards.

The casework, while not aiming terribly far beyond the basic cosmetics for which the brand is known, is better finished than in other recent Audio Note products, while the execution of the top-loading bay is impressive: Its manually operated sliding door feels solid and smooth, so much so that I was surprised when I disassembled the CD-4.1x and saw how simple it actually is. Build quality is fine inside and out, with neatly laid-out PCBs and very clean solder joins.

Installation and setup
There are few things in life more simple than installing a one-box CD player in an existing music-playback system—which is, I suppose, one of the great reasons for the medium's success. So it was with the Audio Note CD-4.1x: I plugged its AC cord into the same power strip as everything else in my system, ran a long pair of Nordost Blue Heaven interconnects (see below) between its analog output jacks and a pair of line-level input jacks on my Shindo Masseto preamp, toggled its cannily hidden rear-mounted power switch to On, and all was revealed. The front-panel display, which glows an attractive blue, was about as basic as these things get, although a dimming switch on the CD-4.1x's front panel is a welcome inclusion.

Playing a CD was a simple matter of sliding open the bay's lid, placing a CD on the transport hub, securing it in place with Audio Note's chunky little magnetic puck, and closing the lid. At that point the CD-4.1x reads and displays the contents of the disc—all a bit more slowly than most other modern machines, but a great deal faster than my Sony SCD-777ES SACD/CD player—and awaits the pressing of Play. No surprises here.

At the very first, the CD-4.1x sounded a little too soft on top. Bearing in mind that the player had been shipped to me direct from the Audio Note factory, without benefit of running-in, I didn't expect it to achieve peak performance with the first CD, but excessively rolled-off trebles aren't among the qualities I associate with an untamed digital source. Thus it was I decided to exchange that 5m pair of Blue Heaven interconnects, on loan from Nordost, for a 1m pair I had on hand. The treble extension noticeably improved. It improved yet again, to a subtler extent, when I replaced the Nordost cable with my own 16-year-old, 1.5m pair of Audio Note AN-Vx silver (which, as ideas go, seemed righter, anyway). I'm not sure what, if any, output-impedance irregularities John Atkinson's measurements will reveal, but the prospective owner should consider herself forewarned.

Audio Note UK, Ltd.
25 Montefiore Road
Hove, East Sussex BN3 1RD
England, UK
(44) (0)1273-220-511

JItterjaber's picture

They still make CD players? 

Thanks for the review, but I would be really curious how a RAM based CD playback (i.e. pure music) on a laptop compares to expensive CD players. I have a feeling this could enlighten people!


mrhyfy's picture

Looking under the cover,,I don't see 12 grand worth!  Sorta looks like chi-fi.

mrhyfy's picture


Archimago's picture

Good review and I'm glad to see equipment like this getting on the test bench and put through its paces.

Obviously, the measurement results are laughable...  No worry however, since I'm sure Peter Qvortrup will happily conjure up some philosophical musings about how frequency respose, accurate waveform reproduction, noise level, jitter are all irrelevant and how these results are those of superior sound reproduction at a mere $12K :-).