CH Precision • C1 Digital-to-Analog Converter/Controller and D1 CD/SACD Player

by Roy Gregory | September 22, 2016


The digital revolution means different things to different markets and people, but in the small corner of the world that is high-end audio, its real impact isn’t to be understood in terms of quality of recordings or longevity of software. Instead, digital’s influence has been felt in two ways: its effect on product tempo and system architecture. The deeper the association between audio equipment and the computer industry, the more the latter dictates terms and the more hi-fi ends up dancing to the computer-industry’s tune. That change can be mapped in many different ways, but for electronics manufacturers, the key indicator is product lifecycle.

If we look at analog technology, the working life of the microgroove record is already approaching six decades (in stereo form; it's considerably more if you include mono). That stability is mirrored in turn in the replay hardware that goes with it. Turntables from the likes of Thorens, Linn and Rega, to name just a few, have had shelf lives that exceed 30 years, and working lives that extend beyond that. There’s no reason why an original Rega Planar 2 built and bought in 1975 shouldn’t still be going strong today, while, outwardly at least, current Rega products are still recognizably the product of the same DNA.

Now compare that to a CD player. Few if any CD players remain competitive (or in many cases even useable) into their second decade. Why? Because key components like DAC chips or transports are no longer available. That’s because we increasingly depend on manufacturers that supply the computer industry to produce those components -- and if the computer industry isn’t buying, those manufacturers aren’t building. Possibly the most obvious example of this is the number of stillborn CD players -- projects that, each time they approached readiness for market, had to be reengineered to accept a different transport as the existing one was discontinued. The life span of DAC chips is nearly as short, and look at the shelf life of the digital-to-analog converters that are built around them. With data rates constantly ramping up and high-res downloads embarking on a new numbers-driven arms race, the digital landscape is now changing so quickly that many traditional manufacturers are struggling to keep up. It’s instructive to look at what happened to the camera industry, where brands like Hasselblad and Leica are now just vanity badges for digital-imaging companies, technological specialists adding a bit of old-school luster to the corporate masthead and tapping into the installed customer base.

The other major impact that digital has had on audio is a seismic shift in system architecture. Analog systems could reliably be expected to consist of a front-end (record player, tuner and/or tape deck), amplification and speakers. Beyond that, the electronics might well divide into a preamp and separate power amp(s) -- and you might even find the latter situated beyond the speaker crossover in an active configuration -- but the basic building blocks and the junctions between them were incredibly well defined.

Then CD happened. First, the phono stage was ousted from the preamp, which transmogrified into a new product category, the line stage. Meanwhile, the CD player was dividing like a cell growing, splitting first into transport and DAC and then sprouting external power supplies, clocks and, more recently, streaming functionality. Soon the line stage’s system-control functionality was under threat as digital engineers looked to incorporate it into the DAC chassis or do away with it entirely and move toward digital signal transfer.

Suddenly the old functional delineations had broken down, and it’s now no longer clear which boxes or how many boxes you need, or what those boxes do. On the one hand you can have an all-source, all-singing and all-dancing one-box solution like the Devialet, a single compact chassis that purports to do everything you might ever want it to. On the other, there are multi-box systems from single manufacturers like dCS or Esoteric, or systems cobbled together from various individual specialists, that subdivide reading, conversion and control functionality.

All of which leaves the end user in a quandary: buy into a one-box solution and you are relying on the manufacturer to keep it up to date and upgradable -- and there’s no guarantee that the system infrastructure will be able to accommodate some new, revolutionary change in format, processing or hardware; work with a bunch of separate boxes and accept that you are paying extra for all those expensive chassis and power-supply components as well as potentially compromising performance when it comes to interfacing them. Contrary to popular opinion in certain circles, it’s actually easier to understand why digital cables have a potentially profound impact on audio performance than their analog equivalents. Throw in the range and inconsistency of the interface terminations and you have a deep well of sonic poison just waiting to wreak musical havoc.

This lengthy preamble brings us to the subject of this review, CH Precision’s digital-replay system and one possible (albeit expensive) solution to the dilemma facing modern digital audiophiles. On its face, it's a simple two-box transport-and-DAC setup with a few extra digital inputs and a variable analog output. But there’s more to this Swiss pairing than meets the eye, which is probably just as well, as few if any products in my experience have been quite as aesthetically enigmatic or functionally impenetrable as these -- at least on first acquaintance. For a while now, a favorite source of amusement chez Gregory has been inviting industry visitors to "play a disc," handing them the CD in question and then standing back while they try to figure out which box it goes in -- and then, having finally gotten that far, how to get it open.

Let’s look a little closer at CH Precision and the products they’ve produced, starting with the D1 disc player. Hailing as it does from Switzerland, the CH moniker seems like a pretty obvious pointer. If so, then it’s also a convenient coincidence. The "C" and "H" in this instance stand for Florian Cossy and Thierry Heeb, company principals with a shared background at Goldmund (not to mention Anagram and Orpheus Labs), where they specialized in amplifier and digital design, respectively. It’s an interesting and pertinent history, as anybody who has experienced a Goldmund system will attest. Anybody who has experienced Goldmund the company might also describe that experience as sonically amazing, fascinating, groundbreaking, technologically provocative, unreliable, flaky and ultimately frustrating (my view, I hasten to add, not that of C or H). Rarely has a company seemed so blessed with vision, startlingly innovative products and technology -- yet so incapable of delivering it to market or servicing it once it has gotten there. These things are certainly cyclical (and currently Goldmund certainly seems to be on the up), but one thing’s for sure: it’s fair to say that over the years the company has burnt a lot of bridges, which isn’t exactly an encouraging environment for their designers, so perhaps it’s hardly surprising that Cossy and Heeb (as well as others) have ultimately struck out on their own.

Nor should one overdo the Goldmund connection. Whilst there are certainly some common DNA strands apparent here (the primacy of speed and bandwidth coupled to serious mechanical grounding) the CH Precision components don’t sound like Goldmund or share that company’s system concept, with its reliance on digital signal transfer, distributed decoding and active speakers/DSP crossovers. In fact, in many ways the CH components follow conventional analog system architecture -- at least they appear to. But then, by now, you’ll have realized that when it comes to CH Precision, nothing is quite what it seems and appearances are most certainly deceptive.

From the outside, the D1 looks like a large, if otherwise conventional, preamp. The one thing it really doesn’t look like is a CD player: no obvious drawer and no row of transport control buttons. Instead, you just get a large central display and a single circular, concentric control. The chassis has a deep, square footprint but is otherwise largely featureless, apart from four discs set flush in its top, an overall aesthetic that sits somewhere between serious and seriously bland.

The first surprise (shock might be nearer the mark) comes when you try to pick it up. The D1 -- a mere CD player -- weighs in at 32 kilos, or just a touch over 70 of your old-world pounds. The second surprise greets you once you take a look at the rear panel. The various inputs and outputs are arranged on small, separate back plates, each section dedicated to a given purpose. The review unit was fitted with a digital-output board (four options: AES/EBU on balanced XLR, TosLink optical, S/PDIF (inexplicably) on RCA, or proprietary CH-Link, of which more later), analog-output board (balanced XLR or single-ended RCA for both channels) and a Sync I/O board with BNC input and output for external clocking. It also had two blanking plates, which is when the penny drops. As a quick glance at the manual confirms, the D1 is an honest-to-goodness, modular card-cage design.

With one slot dedicated to the Sync I/O board, that leaves four free slots to work with, allowing you to configure the D1 in a number of different ways according to your specific requirements: by selecting the appropriate cards, you can create a dedicated digital transport, or an analog output device, with dual-mono, stereo or 5.1 surround-sound output options. If you set it up with standard analog stereo outputs, you can always upgrade those later to dual-mono cards, add a digital output card, or extra channels to the system. The D1 is supplied with a single output card as standard, although the review unit was configured so that I could use it both as a standalone player and as a transport. This versatility is particularly interesting, because it means you don’t have to pay for facilities you are not going to use, or change out the machine because your overall system topology/architecture changes. Score one for sound engineering and common sense. (I’m not sure the value-for-money tick applies at these prices, but it’s nice to know that you're not spending even more than absolutely necessary).

That modular theme carries over to the inside, where the player’s construction is subdivided into discrete elements. There are separate, independent sections for the (heavily isolated) main power supply, transport and control hardware, the display, core processor and the card-cage architecture. It’s an arrangement that should both ease servicing and facilitate any future upgrades. Now, we’ve all been here before, and theory and reality seldom seem to align quite the way you hope, but as well as the promise of extended life span, the modular construction also helps significantly with the mechanical grounding of the player as a whole. Lift the lid and you can’t miss the Esoteric VMK-5 CD/SACD mechanism, the go-to audio-specific transport for serious high-end disc players. The mechanism provides mechanical clamping across the entire width of the disc, but CH takes that a whole stage further, mounting the whole assembly to a 15 kilos (33 pounds) steel base plate to ensure a stable ground path for any spurious mechanical energy. The four feet contain integral spikes that can be adjusted from above by removing the discs in the top plate, while the discs themselves can be replaced with steel cups designed to accept the spikes of a CH unit stacked on top, thus providing a continuous mechanical ground path. It’s a nice idea in theory, but I question whether anybody spending the sort of money that a complete CH system costs would risk compromising performance by stacking the electronics. As with many of the (almost countless) facilities and options built into the CH products, I wonder whether this is a case of something that looks good on paper but seldom actually gets used.

The power supply receives special attention. Two electrostatically shielded transformers are used, the main unit supplemented by a much smaller one to provide a genuine low-power standby mode. Both transformers are mounted on a separate steel plate spaced on elastomer isolators from the main chassis itself and housed in their own separate internal enclosure. The DC supplies for each section are heavily regulated using discrete components to ensure thermal stability and avoid cross contamination between audio and control/display circuitry. CH is tight-lipped about the DAC chips employed in the D1, stating simply that there is one Delta/Sigma chip per channel, but it is interesting to note that the CH-Link allows coded transmission of raw SACD data in its native 1-bit/2.8224MHz format (rather than via conversion to PCM).

So, despite the virtual absence of external controls, the D1 is actually a surprisingly versatile unit. Not only will it will play CDs and SACDs, it can be configured for stereo or multichannel applications and it can act as a player or a transport. It is upgradable within that functionality and within its own architecture, so that if technology offers or imposes a change in hardware, it can be instituted with minimum loss of existing investment -- and where digital components are concerned, that’s a rare situation indeed. Just be aware that the USB and Ethernet connections that you can see in the picture of the D1’s rear panel are for system-management and network-control purposes, not connecting external sources.

Still, that’s a pretty fair range of functionality for one box with only two controls. Ah, yes, those controls. CH Precision has opted for a clean, minimalist aesthetic, with sharply defined contours and no instructional labeling to clutter the fascia. Instead they rely on that large, central display to keep you abreast of proceedings. All functionality is accessed through the dual-concentric "rockers" with successive twists and prods producing the desired results (see sidebar), but even once you are familiar with the unit, its operation never quite reaches the level of intuitive, and even after several months with the CH Precision pieces, I still have to think each time I enter a command -- and each time I don’t, I end up with the machine performing some entirely unintended function. Now, ergonomics, style and operational elegance are very individual things. On balance I’ll put up with quite a bit of functional clunkiness to achieve superior looks or performance -- after all, I still play records -- but the D1’s control interface is a step too far for me.

Of course, it wouldn’t matter if all the functionality were duplicated on the remote control. It isn’t. The D1's remote is a five-button affair that allows you to access the basic functions (mute, play or stop discs and skip tracks in either direction). Longer pushes on each button allow you to power the unit up or down, search forward or backward, or reverse signal polarity -- but that’s your lot. The C1's remote is just as basic, and while the company does offer a control app, this will only run on Android phones or tablets, so if you are seriously contemplating the CH route to audio nirvana, first make sure that your upward path won’t be derailed by operational frustrations. Given the sheer complexity of these products and the plethora of options they offer, this is something that CH could and certainly should improve. Fortunately, by its very nature, extending the control app to Apple devices and evolving the user interface shouldn’t be too testing.

Other than its sheer mass, setting up the D1 is perfectly straightforward. One thing was immediately apparent in all the situations and systems that I experienced. The unit sounds much better when solidly coupled to its support. The round feet include O-ring decoupling/surface protectors. Wind the spikes down and you bypass them, as well as being able to level the machine if necessary. The result is crisper definition, greater transparency and quicker, wider dynamics. Move to Nordost Sort Kone TCs and you’ll extend performance even further, as well as add greater weight and color to the mix too. Just remember that if the D1 is standing on its spikes, any attempt to slide it to adjust positioning will dig substantial trenches in all but the hardest supporting surfaces. The C1 is a relative lightweight in comparison, but even it managed to scar one of my Hutter shelves for life.

Once you have the D1 up, running and playing the disc/track you want, how does it sound? Like any modern, configurable digital product that depends on your choice of filter: after extensive listening I opted for the Minimum Phase-Low Ringing option for PCM and Minimum Phase for DSD, which gave the greatest sense of natural flow and musical momentum. The Apodizing and Sharp alternatives sounded progressively higher definition but also more sterile. The differences are subtle, but hear the changes a few times and you’ll soon fix your own preferences.

With that attended to, you can actually get to enjoy some music, so, once again, just how does the D1 sound? In a word, composed. Unflustered and unhurried, the D1 produces music with a sense of stability and contained control -- neat, detailed but a little bland. You never get the feeling that the signal is going to get the system into trouble, but then you never quite get that edge-of-the-seat drama that comes from live events either. The soundstage is pushed back behind the plane of the speakers, with depth, separation, tonality and both dynamic range and resolution compressed. Overall, the performers lack individuality, the performance immediacy. On Arturo Benedetti Michelangeli’s superb concert performance of the Beethoven First Piano Concerto (with Giulini and the Vienna Symphony [Deutsche Grammophon Gesellschaft UCGG-9044]) the performance lacks its normal drama and impressively emphatic orchestral dynamics, the delicacy, poise, flow and phrasing that characterize the piano part, normally such features of the SHM-SACD.

At the other end of the technological (and musical) scale, the wonderfully uncomplicated, driven R&B of Wilko Johnson and Roger Daltrey on Going Back Home [Chess CRCD2014] sounds compact and solid but without the sheer unstoppable energy that makes this such a great outing. For a disc that marks Daltery’s return to form and might well have marked the great Wilko’s final gig, it sounds flat, lacking urgency, vitality and that slightly abrasive, just inside your personal space immediacy so reminiscent of the Feelgoods at their best. Daltrey might not curl a lip quite as convincingly as Lee Brilleaux, but he’s way better when it comes to holding a tune.

Which leaves the D1 as a stolid, reasonably capable but ultimately unexciting performer. Its shortcomings are far less apparent compared to the run of the digital mill, where it comes across as a stable and controlled player, a safe pair of hands that won’t let you down, but ultimately won’t really excite you either -- which at a touch over £24,000 (including an analog output board) is more than a little disappointing.

Now, under normal circumstances you might wonder why I’d be wasting my time on an expensive but ultimately musically unrewarding product. The answer is simple: although the D1 might not impress as a standalone solution, connect it to the C1 DAC/controller and suddenly it’s all change. Michelangeli recovers that remarkable poise as his hands, almost dancing across the keys, bringing Beethoven’s phrases to vivid life. The Vienna don’t just wake up, they nail it, while you can hear the part that Giulini’s deft direction plays in conjuring the overall drama, creating a performance that fully justifies the explosive applause that greets its conclusion. Meanwhile, the Daltrey/Wilko show finally gets into gear, not just rolling along but propulsively insistent, just up front enough to get right in your face -- right where this music belongs.

How come the dramatic (and believe me, it is dramatic) transformation? To appreciate not just why the differences are so great but why the scale of those differences makes sense, we need to look in detail at not just the C1, but the way it interfaces with the D1. Built into exactly the same chassis as the player and with a central display window that’s the same size, the C1 is virtually identical in appearance to the D1. The only giveaway, when you get up really close, is the outline of the disc drawer in the D1’s display window. Otherwise, the units might as well be identical twins, with only the content of the display to separate them -- assuming that you haven’t defeated it. Internally they’re twins too, with the C1 mimicking the D1’s modular architecture and card-cage construction, with each major circuit block independently realized, in this case including the sophisticated clocking circuit.

Just like the D1, the C1 chassis accepts five slot-in boards, although in this case two slots are pre-designated for the Sync I/O and control boards. The latter is actually used to access the C1 for service and software upgrade purposes, although it can be upgraded to include LAN functionality so that the unit can become a network player. The remaining three slots can each house a digital, asynchronous-USB or analog-input board as required. Each digital board offers four inputs (AES/EBU, TosLink optical, S/PDIF on RCA and CH-Link). The analog board offers a pair each of balanced and single-end inputs. With the three available slots, in most systems it’s tight but doable, especially as the network option effectively duplicates the USB input for file replay -- and is certainly considered the preferable option by CH Precision. When it comes to outputs, you get one pair of single-ended RCAs and one pair of balanced XLRs, spread across two cards and equivalent to the D1’s dual-mono analog output option.

Internally, you’ll find a few more significant differences, mainly in the type and configuration of the DAC. Where the D1 uses a pair of Delta-Sigma chips, the C1 uses two pairs of Burr-Brown PCM1704s in a fully differential array. This in turn feeds a high-current, fully differential output stage, via a wide-bandwidth current-to-voltage stage and a fully discrete, feedback-free low-pass filter. The defeatable volume control (should you want to use the C1 as a standalone DAC) is a sophisticated hybrid digital/analog design. The dual-mono DSP chips used for the digital-volume scaling are also responsible for the conversion of incoming DSD to PCM for subsequent decoding and synchronous upsampling of signals to 705.6 or 768kHz. The two clocks (22.5792MHz for 44.1kHz and multiples, 24.576MHz for 48kHz and multiples) are located immediately adjacent to the DAC chips and run from their own dedicated and galvanically isolated supply. The analog inputs are passed through their own A-to-D chip slaved to the DAC’s master clock, which passes a DSD2x-resolution signal through dual-mono DSP chips into the DAC. This allows the C1 to process analog signals using the same switching, volume control and output stage it employs for digital sources. Converting analog inputs to digital and back again might seem perverse, but let’s not forget that it’s exactly what happens in the remarkably impressive Wadax Pre 1 Mk 2. CH Precision is not alone in treading this path, or in making it work.

Viewed overall, the C1’s internal architecture is a massively more sophisticated and heavily engineered solution than the onboard decoding and analog output installed in the D1, which goes a long way to explain the sonic differences -- but doesn’t quite tell the whole story. Connecting the D1 to the C1 creates two additional options. The first is the proprietary CH-Link connection, an £800 umbilical with multipin edge connectors at each end that passes the digital signals (including DSD) directly from the D1 to the DAC in the C1 as well as control data between the two. The second is the Sync I/O clocking board that allows you to slave the D1 to the master clock in the C1, theoretically eliminating jitter from the data transfer. Both have a profound impact on musical performance. CH makes considerable claims for the overall linearity and temporal accuracy of the PCM-based decoding and output stage of the C1, along with its lack of high-frequency overshoot or ringing and its wide dynamic range. When listening to the D1/C1 pairing, those are claims you have to take seriously.

If you want proof of this particular pudding, look no further than the strident, off-key interjections that punctuate the open piano passage of the Beethoven. The D1/C1 pairing deliver a stark, musically effective contrast, itself a stark musical contrast to the clanging discord that I’ve heard set off the Wilson Alexia tweeters driven by the dCS Vivaldi stack. One of the key indicators that I listen for when assessing any piece of equipment is its ability to separate different performances or discs of the same work. It’s a little like asking an actor to run through different characters or accents: can he take on a different persona, a different voice, or is he simply himself -- is he an Andy Serkis or Timothy Spall, or is he Harrison Ford or (Lord help us) Sly Stallone. When it comes to digital source components, few have made the differences as obviously apparent as the CH Precision combination (or system). If you want musical vocabulary, diction, accent and grammar, then look no further.

Let’s use the Dvorak Cello Concerto as an example. Start by comparing the JVC XRCD version of Piatigorsky’s reading with Munch and the BSO [JVC JMCXR-0014] to the RCA SACD issue of the same recording [RCA 82876 66375 2]. The XRCD offers a nice sense of easy flow and musical momentum, but it is also distant, warm and wooly, with a flattened soundstage that lacks air and immediacy -- especially when compared to the Living Stereo LP. Switch to the SACD and the superiority is brutally apparent. From the first notes the expansive soundstage is closer and far more clearly defined, with a sense of dimensional coherence that simply escapes the XRCD. Instrumental placement and separation are far better and more natural, as are tonality, texture, dynamics and tempo. The combination of transparency and immediacy generates a real sense of presence, that elusive quality that makes recorded performances convince.

If you ever wanted a slam-dunk case for SACD’s superiority here it is in a two-disc nutshell. Except that things aren’t quite that simple. There’s no question about the sonic superiority of the SACD, but what about Piatigorsky’s performance? Time to reach for a few alternatives.

First up, Jean-Guihen Queyras recorded in 2005 by Harmonia Mundi with Jirí Belohlávek and the Prague Philharmonia [HM SACD HMC 901867]. On first hearing, it’s easy to dismiss the Queyras performance as lacking the body, power and drama of the vintage RCA, but it’s worth persevering. Harmonia Mundi’s recording reflects modern techniques and style, with a tighter focus on and separation of instruments, a leaner, less sumptuous overall balance. It might rob the opening bars of some of their dramatic bombast, but by the time you reach the second movement, which requires greater delicacy and sensitivity in its playing, the fineness and poise of Queyras’s line becomes a thing of beauty. Overall, the orchestral coherence and Piatigorsky’s phrasing carry the day, but the HM disc certainly shows another side to this work: more intellectual, less romantic and certainly worthwhile.

Which brings us to that other audiophile contender, Starker and Dorati on Mercury. This time let’s limit the options to the original CD issue [Mercury 432 001-2], the subsequent SACD [Mercury 475 6608] and the LPCD [Hugo 480 613-9] -- there are others, but these are the ones that matter. With the original CD issue, the presentation and performance are immediately recognizable to anybody familiar with the record. It’s bigger, bolder, more driven and far more dramatic than the RCA offering, with a presentation that favors body and impact over spatial coherence. The result can be a bit clumsy in places, lacking the grace, inner detail and dynamic shadings that characterize the LP, but it’s undeniably impressive and musically engaging. In comparison, the SACD is leaner, cooler and almost stilted, lacking the coherence that comes with the RCA SACD and the sheer weight and momentum that you get from the Mercury CD. It’s a pared-away, almost skeletal presentation that suffers in temporal terms too, sounding angular and mechanical -- definitely a poor second to the standard CD.

By the time you reach the second movement you’ve lost interest in the SACD, but the standard CD makes a fascinating contrast with the RCA SACD and also the LPCD. The Mercury CD sounds more muscular and less lyrical than Piatigorsky on the RCA SACD, almost as if illuminated in the thinner, brighter light of morning, rather than the softer shades of evening. On this basis, you’d have to conclude that Piatigorsky is more in sync with the music than Starker, whose reading is more literal and far less evocative. That is, until you play the LPCD. Not only does this match the body, drama and energy of the CD, it brings all the dynamic resolution and spatial coherence of the LP. The Mercury recording has never had the same sense of an overarching acoustic space as captured by RCA, but the space and relationships within the orchestra are vividly captured -- and they’re present here on the LPCD. The improvements in separation, tonality and texture are the result of more accurate harmonic resolution and lead in turn to greater temporal sophistication. The performance now has swagger and bravado rather than clumsiness, a sense of restraint to match its more gung-ho moments.

Once again it is the second movement that is truly telling. Starker’s playing never reaches the lyrical heights of Piatigorsky's, but the LPCD makes greater sense of his phrasing and more of his dynamic contrasts. It also gives a real sense of the intensity in his playing, which really ratchets up the drama and presence. Which do you prefer, Starker’s poise, control and lucid lines or Piatigorsky’s more romantic and lyrical style? That’s the whole point: with the best discs of either recording the preferences become purely musical, the recordings a means to that end.

Great, but what does this tell you about the CH Precision duo? First and most important, it underlines the combination’s essential honesty and evenhandedness across formats. Its insight into the quality of discs is explicit, yet it is also perfectly balanced. These various Dvorak recordings demonstrate a number of truths: that different labels have house sounds and that the style of performance and recording evolves over time; that great performers and great performances can sound very different and tell very different stories; that higher resolution is no guarantee of higher quality; and that there’s considerable life in the CD yet. None of this is news, but the CH Precision units make the various cases with an emphatic clarity that banishes doubt and skepticism. They demonstrate just how good a job Mercury did with those early CD issues -- and just how poorly Emil Berliner did with the SACD transfers compared to the work that Soundmirror did on the Living Stereo back catalogue.

What this also suggests is that when it comes to the limits of performance, the recordings are going to be the dominant factor. Where does the D1/C1 pairing fall short compared to the best of the rest? If the large-scale dynamic swings of the Beethoven and Dvorak discs play to its strengths of stability and secure timing, the driving R&B of Wilko to its rhythmic integrity and sense of dynamic purpose, then let’s look at the opposite end of the musical spectrum to see how it fares presented with smaller-scale and more intimate material.

The double, gold CD reissue of Ella Fitzgerald Sings The Cole Porter Song Book [DCC GZS-(2) 1079] offers the perfect window onto the CH Precisions’ way with smaller works. The straight-ahead, up-tempo rhythm of "Too Darn Hot" or simple, sparse progressions of "I Get a Kick Out of You" are handled well enough, but switch to the more complex phrasing of "Anything Goes," "Miss Otis Regrets" or "Let’s Do It" and the sinuous, rhythmic flexibility and natural sophistication that Ella brings to her vocals are diminished, reducing the songs’ sense of natural pace and progression, when compared to the performance of the Wadax Pre 1 Mk 2 or Neodio Origine, which manage a greater sense of communication and intimacy. The CH Precision pieces slow the undulating smooch that underpins "Let’s Do It," diminishing its suggestive sway and the equally suggestive hesitations that Ella introduces into the lyric.

This level of rhythmic subtlety is where the D1/C1 pull up short of the fluid ease of the very best performers in this regard. Likewise the dirty groove that anchors the Art Pepper track "Las Cuevas De Mario" (Smack Up [Analogue Productions CAPJ 012]) loses its smut and all gets cleaned up; your mother might approve, but if this is your staple musical diet, I’m not sure you will. This isn’t about pace, fast or slow; it’s about variation. It’s almost as if the CH units’ adherence to strict meter inhibits rhythmic expression. You’ll not notice it on Beethoven or Bach, indeed quite the opposite. They thrive on the clarity of structure and pattern that results. Likewise, the vast majority of rock and pop is played with aplomb, but where it’s more of a problem is inevitably on more free-form material, with jazz being the obvious case in point.

How big a deal is this? That depends on your musical tastes and susceptibility to the issue. In other words, it’s something to address by listening to your favorite music. For many it will be perceived as a welcome degree of control compared to more-enthusiastic competition; for others, a necessary and acceptable adjunct to achieving the player’s exceptional degree of tonal and harmonic development. Either way there’s no escaping the slightly studied and cerebral presentation that goes with the CH products. It’s not that they’re slow and it’s certainly not that they're dynamically challenged. It’s more a case that they never let go -- which is exactly why one listener will love what the D1/C1 does and another will find himself admiring it, rather than falling in love. Welcome to the ever-shifting reality that is high-end audio.

How best to sum up the CH Precisions’ balance of virtues? Let’s go back to where we started and piano -- but this time let’s take a pair of classic jazz albums, both piano trios, both from the early 1960s and yet from opposite ends of the stylistic spectrum: Bill Evans’ Sunday at the Village Vanguard [Riverside/OJC20 140-2] and Oscar Peterson’s We Get Requests [Verve 521 442-2]. Playing them back to back on the C1/D1 is an illuminating process, both when it comes to contrasting the performers and understanding the player. The CHs’ crisp, unforced, clarity brings a definite quality to Evans’ staccato playing, capturing his coupled notes and their weighting, especially when he makes space for Scott LaFaro’s extended bass runs, an element that especially benefits from the note-to-note stability and precision that come with the CH units. It’s almost as if they are concentrating on the notes themselves and the crucial spaces between them, rather than the musical lines that flow through them. Thus, Evans’ couplets and shorter note sprays are beautifully rendered, but at some expense to the sense of overall shape and melody, while his longer lines on a track like "Alice" are notably more lively and engaging.

Move on to the Peterson and it’s a whole different picture. His busier, more continuous lines are more fluid and give the tracks more shape, the album greater overall coherence. It’s almost as if by joining the dots himself, he’s saving the system from having to do it for you. But once again, the FIM version of this disc [LIM K2HD 032] displays a startling degree of superiority over the standard issue, a timely reminder of the brutally frank, ungarnished musical presentation of the CH Precisions. When it comes to phrasing and melodic shape, the CH pairing is handily bettered by the almost analog-like reproduction of the significantly more costly Wadax, but also by the significantly more affordable Jeff Rowland Aeris. However, the latter doesn’t even come close in terms of definition or the anchored sense of absolute stability engendered by the CH. It’s these three qualities that characterize the C1 and D1 used in tandem: clarity, stability and control. What you have to gauge is how they balance against the sense of musical line, flow and expression -- and how comfortable you are with where they sit on the definition/musicality continuum. It’s tempting to say just left of center, but that’s on my scale, and when it comes to this measure, each listener sets his own end-stops. If my natural leanings are to the right (at least in this context), then the D1 and C1 are about as far left as I’d be happy to go: musical engaging enough to genuinely satisfy but with the added bonus of utter imperturbability and an almost forensic level of sonic insight. For me, the CH combination delivers its stability and resolution at lower cost (monetarily and musically) than the other extreme-definition options that I’ve used.

Mentioning (the not inconsiderable) question of cost brings me to perhaps my greatest personal frustration with the D1 and C1 pairing. Put simply, it is that they are such a successful pairing. The C1 is impressive on its own as a DAC/controller, but its performance with other transports, such as those from Wadia and CEC, definitely loses the musical authority and explicit confidence that come with the D1 and CH-Link. I was examining these units as a disc-replay solution and for a listener wed to USB or LAN file replay, then the C1 makes a much stronger case as a standalone or interim purchase. But coming from the other digital direction, the logical stepping stone would be to start with the D1 as a standalone unit -- a role in which it gives too much away, musically speaking, at its elevated price. It’s somewhat ironic, given the modular nature of the components themselves, but the D1 makes much more sense as a transport than it does as a player -- which does rather undermine the step-by-step approach to building a CH system, committing the purchaser to the combined cost of a D1 and C1 together, which will put them beyond many listeners’ consideration. Having said that, other similar systems from the likes of dCS and Esoteric will weigh just as heavily on your wallet. I just wish, on a purely personal level, that the D1 player was as much of a star at its price as the D1/C1 combination so demonstrably is at theirs, but perhaps that’s asking too much.

The other point worth making is that the way in which CH units combine to create a symbiotic whole extends beyond the D1 and C1 into their complete system solutions. Add the A1 amplifiers to the mix and the sense of musical coherence takes another major step forward. Use the amps with other line stages and source components and as impressive as they are, they lose color and dexterity, diminished in terms of musical articulation and fluency. Reunite them with the D1 and C1 and the whole blossoms together, the amps starting to breathe while the D1 and C1’s musical rigor suddenly starts to pay serious dividends. Rather like the Mark Levinson Reference components from years back, the results may not be perfect, but the system gets way more right than it does wrong and definitely makes for musically satisfying listening -- at a slightly frightening price. Also like the Levinson units, the CH equipment sounds substantially better running balanced -- which rather raises the question, Why isn’t there an analog input board offering two sets of XLRs?

At the end of the day, there is an element of risk in the CH Precisions’ essential honesty. Indifferent recordings will be shown in all their hideous, naked glory -- not unlistenable, but the flaws will be only too apparent. Of course, the flip side is that great discs sound genuinely fantastic. Let’s face it, you don’t get much more hackneyed than We Get Requests, yet playing the FIM silver CD on the D1 and C1 was both a (guilty?) pleasure and a reminder as to why this recording is as popular as it is. Somehow this really seems to fit the CH ethos: The kind of customer who will appreciate and purchase these products, revel in their intellectual rigor, enjoy the almost infinitely configurable nature of their user interface and extreme flexibility is exactly the same customer who will diligently search out the best discs and the best performances.

The D1/C1’s performance is firmly grounded in their temporal security, the digital equivalent of rhythmic lockstep, a quality that maintains musical coherence in the face of even the grossest recording and mastering provocation. It means that they don’t pull recordings apart and completely dismantle them. Instead, where necessary, they impose order -- at the extent of some expressive fluidity and grace. It means that you don’t have to have great recordings to enjoy the CH Precisions’ performance, but that you’ll enjoy them all the more. There are those for whom that degree of insight into the reproduction process will detract from the performance itself -- but there are just as many for whom it will introduce a welcome degree of certitude into that other process: selecting discs and building a library.

As it is, the CH Precision D1 and C1 pairing makes it onto my extremely select digital replay top table, alongside the Wadax and Jeff Rowland DACs, the Neodio Origine CD player, and the CEC transport. It is by some distance the most musically emphatic member of the party and also the de facto recommendation for SACD replay.

Prices:  D1, from £22,800; C1, from £18,500; various input and output boards, from £1500; Sync I/O board, £800; CH-Link cable, £800.

Warranty: One year parts and labor.

CH Precision Sàrl
ZI Le Trési 6D
CH-1028 Preverenges

Wilson Benesch Ltd.
Falcon House
Limestone Cottage Lane
Sheffield, S6 1NJ
+44(0) 1142 852656

Choices, choices

Like many modern -- and especially modern -- digital products, the CH Precision D1 and C1 are microprocessor-controlled and multi-configurable. Where facilities such as trimming individual gain levels and setting preferred absolute polarity for each input used to be the thing of science fiction, now they are commonplace. Throw in the modular nature of both the D1 and C1 and the variables are almost unlimited. It’s no exaggeration to say that pretty much anything you can think of is covered -- and quite a lot you never even considered.

Use the D1 and C1 together and beyond the choice of inputs and outputs, top-level operational options include a choice of three different filters for PCM decoding and the same three (or none) for DSD --with each input individually configurable. Unused inputs can be disabled and any input can also be set to unity-gain mode for use with an external processor. Identity, gain, balance, clock source, maximum volume and maximum initial volume can also be set for each input. The USB input can be configured for 1.0 or 2.0 operation, with or without its audio power function. The C1 I received had no phono input installed, but if it had, then (according to the manual) I could have selected any one of 14 different EQ curves, including all the usual suspects. The power-on LED can be defeated (or left on when the display is defeated), while the actual content of the display can also be selected. In addition, the display color and brightness can be set for each type of source (DSD, PCM or analog) just in case you forget what you are listening to. You also get standard operating options like mute and repeat.

Now, on the one hand all this flexibility is to be applauded, but if we rework the old adage, just because you should be able to do something doesn’t mean that you can. Let’s be clear here: what I’m talking about is operator error. Remember that each CH box runs off that single (unlabeled) concentric, rotary control. That gives you a choice of inner and outer clockwise or counterclockwise motion, plus a long or short push on the central knob -- or six actions to select all of those various options (and I haven’t even gotten to the various network, system-management and product-status settings). That means menus -- lots and lots of menus. Once you get beyond the absolute basics (open/close, play, skip forward or back) you are into a world of stacked menus. So, for example, to set the D1 to repeat requires a grand total of 15 (and yes, you did read that right) push or rotate commands -- and believe me when I say, that with that many options, the text in the menus is pretty darned small. Fortunately, there is an underlying logic and a little trial and error will start to reveal it. The biggest challenge is that with so many options in each menu, it takes time to scan the available choices -- time the products don’t give you. Linger too long on a single screen and the unit reverts to stasis.

By now you’ll have gathered that, at least on first acquaintance, the control interface of the CH products might rate somewhere between impenetrable and user-hostile. Throw in a manual that could easily double as a door stop (the C1’s instructions run to 62 pages of densely packed information of which quite a bit is contained in diagrams and flow charts/tables) and you might be tempted to give up there and then. But in practice, a little familiarity goes a long way. The logic does emerge, the key operational functions become something approaching second nature (while there’s also the option to establish a range of user-defined short cuts to chosen operations) and whilst initial setup and configuration may well be something of a voyage of discovery, most of the choices will be a one-time thing.

Bottom line -- currency is everything: the more you use the CH interface the easier it becomes, whether on the front panel or a wireless device. It will definitely take a little more perseverance than some, but look on the bright side: your system won’t need a parental lock, although there’s probably an option for that too.

However, there is one area in which all this configurable versatility really pays off. Technically outside the scope of this review, it’s nonetheless well worth mentioning the A1 power amps that came along with the D1 and C1. Nominally a classic 100Wpc stereo chassis, the array of five small buttons on the right side of the fascia allow the user to configure the amp. Just what needs configuring on a power amp? Well, how about input (balanced XLR, single-ended RCA or BNC), operating mode (stereo, biamped or bridged), overall gain and percentage of global feedback. Of these, the gain and variable-feedback options are huge benefits when it comes to speaker matching.

For instance the Wilson Benesch Endeavours required zero feedback, while the B&W 805Ds definitely worked better with 20% of global feedback applied, allowing the amp to really get ahold of and control the speaker, something that simply wasn’t necessary with the Endeavour’s more benign crossover characteristics. As anybody who has played with variable feedback will know, the impact and musical benefits of this change will be far from subtle. But what I really like is the ability to set the amp’s operating mode. With two A1s available I was able to choose between mono or biamped operation (in which a single input gets fed to both channels) and opted for the latter. The mode switching meant that I could make the comparison and run the system in either configuration with a single set of interconnects -- a huge practical and cost benefit. I could even have set the feedback and gain individually for both channels of the same amp, allowing me to tune low-frequency damping while running the mid and treble wide open. If only all stereo amps offered this versatility.

-Roy Gregory

Associated Equipment

Analog: VPI Classic 4 with SDS and VPI JMW 12.7 and Tri-Planar Mk VII tonearms; Kuzma Stabi M turntable with 4Point 14 tonearm; AMG Giro with AMG 9W2 tonearm; Acoustical Systems Archon, Allnic Puritas and Puritas Mono, Clearaudio Goldfinger Statement, Fuuga, Kuzma CAR-50, Lyra Etna, Dorian, and Dorian Mono cartridges; DS Audio DS-W1 cartridge with matching equilizer; Stillpoints Ultra LP Isolator record weight; Connoisseur 4.2 PLE and Tom Evans Audio Designs Master Groove phono stages.

Digital: Wadia S7i and 861 GNSC CD players, dCS Vivaldi and Paganini transport, DAC and Clock; CEC TL-3N CD transport.

Preamps: Connoisseur 4.2 LE, Tom Evans Audio Designs The Vibe.

Power amps: Berning Quadrature Z and Jadis JA30 monoblocks, CH Precision A1 stereo amps in biamp mode.

Speakers: B&W 805D with Track Audio stands, Focal Scala Utopia V2, Wilson Benesch Square Five and Endeavour.

Cables: Complete looms of Nordost Odin or Valhalla 2, or Crystal Cable Absolute Dream from AC socket to speaker terminals. Power distribution was via Quantum QB8s or Crystal Cable Power Strip Diamonds, with a mix of Quantum Qx2 and Qx4 power purifiers and Qv2 AC harmonizers.

Supports: Harmonic Resolution Systems RXR, Hutter Racktime or Quadraspire SVT Bamboo racks. These are used with Nordost SortKone or HRS Nimbus equipment couplers and damping plates throughout. Cables are elevated on HECC Panda Feet.

Acoustic treatment: As well as the broadband absorption placed behind the listening seat, I employ a combination of RPG Skyline and LeadingEdge D Panel and Flat Panel microperforated acoustic devices.

Accessories: Essential accessories include the SmarTractor protractor, a USB microscope (so that I can see what I’m doing, not for attempting to measure stylus rake angle) and Aesthetix cartridge demagnetizer, a precision spirit level and laser, a really long tape measure and plenty of low-tack masking tape. I also make extensive use of the Furutech anti-static and demagnetizing devices and the VPI Typhoon record-cleaning machine. The Dr. Feikert PlatterSpeed app has to be the best ever case of digital aiding analog.