AOM Logo February 1999


Emotional Entanglement on the Periphery of Concentration
The Camelot Technologies Merlin Pro CD Transport, Dragon Pro 2 Mk.II Jitter Reducer/Resolution Enhancer, and Uther v2.0 Mk.II DAC


Jon T. Gale

Have you ever had a moment, while otherwise engaged in one endeavor, when a thought or solution to an unrelated problem suddenly crystallizes? One must wonder about our thought processes when, in trying to focus our concentration on a particular object, we actually at times, perceive less. But in the looking away, or de-focusing of concentration, our cognitive ability is heightened towards minute details heretofore undiscovered. (It is in precisely this point that dooms to failure the blind testing/ ABX process).

Music is language that conveys emotion on a cross cultural basis. We can't test it, we can't measure it. We can however, feel it. Until science is able to quantify this emotional entanglement brought forth from a given piece of audio equipment, we are left, as mere mortals, to the task of listening to and conveying these feelings using our (limited) language via a lengthy review process.

Never have I had in room, a new selection of gear that so thoroughly laid waste to my critical listening facilities. My listening notes literally read as if I had Attention Deficit Disorder. Half-finished sentences and incomplete thoughts abound. This, as we shall discover, was an indicator of something good.

As these Camelot Technology pieces are intended to comprise a complete (digital) front end, this is how the review will proceed, with a slight modification. I decided to perform a piecemeal insertion, front to back, of the three-piece set so as to get some feel for each unit in isolation. At best, a compromise, but certainly more revealing of system interaction than in toto.

Merlin Pro CD Transport
The Merlin Pro Transport neatly distills lessons learned (in both engineering and anecdotal) from twenty years of digital playback, into a product priced directly in the "meat and potatoes" high-end segment. Based on the Pioneer Stable Platter mechanism, the Merlin Pro incorporates a modified control section which minimizes interactions between the transport mechanism and the control logic itself, thus further improving signal integrity. Data leaving the transport is clocked out with a Temperature Controlled Crystal Oscillator (TCXO) for exceptionally good jitter performance. The Merlin Pro also incorporates a very stiff power supply, including a premium quality, multiple-winding toroidal transformer, providing independent power supply to the transport's motor, servo, digital control, digital signal processing and analog signal processing sections. Additionally, the power supply of the Merlin Pro possesses over 35,000 µF of filter capacitance, along with ultra-fast switching rectifiers. It is clear that Camelot has made a brute force attempt at quelling digital separates' arch nemesis, jitter.

To deliver its signal downstream, The Merlin Pro is equipped with no less than six digital outputs, two of which are I2S-compliant. (one is a five-pin mini DIN, the other a six pin locking DIN, which should allow linking to most I2S products). The Merlin Pro's output complement also includes RCA Coaxial, BNC Coaxial, AES/EBU, and optional ST Glass connectors.

While it has the "basic block" visual aesthetic, the Merlin is a handsome unit in its own right. Build quality for this price point is surprisingly robust. (Are you as tired as I am of kilobuck gear being flimsy and noisy in operation?), easily surpassing my EAD T1000 in the knuckle wrap test. Furthermore, the platter mechanism was noticeably more quiet while opening and closing.

The Merlin Pro was virtually unaffected by isolation tweaks. Aside from being mounted on a DIY air platform, (2-3/8" slabs of MDF separated by bubble pack shipping wrap), I tried Audioquest Sorbothane footers and Black Diamond Racing cones with no discernible effects.

My only real ergonomic criticism of the Merlin Pro is due to its recessed operational buttons (fully duplicated on the remote). Even with my long skinny fingers (please, no snickering), I had to continually feel for the buttons before I could locate them.

Sound
The Merlin Pro proved, quite surprisingly, to be the most interesting addition to my system in a long time. Replacing a similar stable platter-based drive mechanism (an aging EAD T1000), yet keeping all other system parameters constant (Kimber KCAG digital link and Audio Alchemy DTI v2.0 DAC), the resulting audible changes were, for the most part, rather subtle. Subjectively, the upper midrange and treble were less ragged - not necessarily smooth, but with some degree of transient "spikiness" seemingly removed. Image outlines were firmer and more well defined. Most profoundly though, was the increase in lateral image spread afforded by the Merlin Pro. I'm not just referring to image placement, although with certain phase manipulated pop records, images falling outside the boundaries of the speakers were placed even further left and right, and were more solid and stable. More importantly, it was a better rendering of low-level ambient cues, (those containing naturally-recorded phase information) that, on certain discs, seemed to double the sense of acoustic space. I should point out that this effect was not the result of a gross exaggeration of L-R cues, as dreadfully dead studio recordings remained, well, dreadfully dead. To my mind, the Merlin's realistic rendering of the soundstage resulted in a huge leap forward in playback realism. In studied terms, the Merlin's ability to present more of the recorded acoustic is likely the result of its ability to decode the full gamut of recorded phase information. In practical terms, the Merlin bathed me in the recorded acoustic and immersed me in a soundscape of realistic proportion.

As a stand alone transport, and used with the standard SPDIF output, (I'll address the I2S output below), the Merlin Pro proved a terrific addition to my system. While I am sure there are better transports on the market, at what cost? The Merlin sang, communicated, and enveloped me with music. It has definitely found a prominent place on my "want" list.

Dragon Pro 2 Mk.II

Dragon Pro 2 MK.II Jitter Reduction Device
The Dragon Pro 2 Mk.II represents Camelot Technology's most recent effort at providing an affordable jitter reduction device. Claimed to reduce inherent jitter in digital sources to below 25 picoseconds, the Dragon Pro 2 uses a multi-phase process to reclock the incoming data stream. To quote from Camelot's web site, "After undergoing jitter reduction and/or resolution enhancement, the digital signal now travels to the output stage of the Dragon Pro2 Mk. 2. Utilizing a high current, high speed dedicated low-jitter driver to present the final waveforms to the D-to-A Converter or Dolby Digital/DTS processor, the output stage of the Dragon Pro2 Mk. 2 has complete optical coupling from all other circuitry. Ultra-high bandwidth coupling transformers on the output of the coaxial and XLR connectors further enhances this unique approach to isolation. Indeed, the output stage of the Dragon Pro2 Mk. 2 operates completely free of any jitter and external clock noise."

Via internal DSP circuitry, the Dragon Pro 2 Mk.II allows the user to enhance the apparent resolution of their digital playback system by adding varying amounts of dither to the data stream. Depending on the input capability of the D/A processor, one can select from 16, 18 or 20 bit performance.

Sound
I eagerly awaited the insertion of the Dragon in my system as it had received much word-of-mouth praise and purported to offer resolution enhancement at a lower price point than the Genesis Digital Lens. The sonic improvements wrought by the Dragon should, I feel, first be put into context. These improvements, while small, were nonetheless decidedly perceptible. (As with any high-performance endeavor, one will always run into the wall of diminishing returns as the performance ladder is ascended. To my mind, the $1500-$2000 price point [in electronics, excluding speakers] is where this law takes effect.) Although the Dragon's effects were greater when fed by the EAD, the following observations were made when it was coupled with its sibling transport, the Merlin, via its stock I2S cable.

As the Dragon is actually two devices on a single chassis (a jitter reduction device and a resolution enhancement device), one could utilize the Dragon Pro 2 solely as a jitter reduction device feeding an older decoder that accepts only 16-bit data. Initially used in this mode (with the resolution enhancement feature switched out), the Dragon easily bettered the v2.0 jitter reducer from the now defunct Audio Alchemy, displaying the usual improvements in which lower jitter levels are manifested; namely slighter deeper silences, subtle increases in both image outline palpability and soundstage stability, and a noticeable reduction in upper frequency harshness. The real improvement though, comes when one takes advantage of the Dragon's integral resolution enhancement capabilities. As I was assured that my Theta processor accepts 20 bit data, the Dragon was used exclusively in its 20-bit mode.

I found it quite interesting that both the Dragon and the Merlin each effected a singular sonic improvement. Not only were these improvements starkly different in nature, but highly complimentary. As noted previously, the Merlin's singular sonic improvement was its generation of a soundstage with wonderful lateral spread. The Dragon, however, brought a none-too-subtle improvement in the depth perspective. While the soundstage as a whole had a greater sense of depth, it was the relative depth of individual instruments that increased most noticeably. In an effort to increase the perception of depth, some processors/transports simply move the stage rearward as a whole. (Usually by simply effecting a slight high frequency rolloff). With the Dragon, the stage expanded dramatically from front-to-back, with the midpoint of the expansion rooted firmly at center stage. Permit me a photographic analogy. A telephoto lens, while allowing one to get much closer to a subject, dramatically compresses depth perspective (which is why the most popular portrait lens is 80-100 mm focal length. It helps flatten cheekbones, chins and noses in a flattering way). Conversely, a wide-angle lens will exaggerate depth queues. Put your face close to a wide-angle lens and your nose appears six inches longer. Now imagine "framing" an orchestra with a telephoto lens. While keeping the orchestra framed, change to a wide-angle lens and the stage will appear deeper with more space between the instruments. This is exactly the effect the Dragon brought forth, without exaggeration. When combined with the Merlin's increase in soundstage width, the Dragon's enticing portrayal of depth resulted in a substantial increase in sonic realism.

Given its superior performance, flawless operation and multitudinous connection capabilities, the Dragon Pro 2 Mk.II is, in my opinion, a must have for all users of digital separates.

Uther v2.0 DAC

Uther v2.0 Mk.II DAC
As is the case with the Merlin Pro transport and Dragon Pro 2 Mk.II, the Uther v2.0 DAC is engineered to minimize jitter in the digital data stream. Its input stage virtually duplicates that of the Dragon Pro 2 Mk.II, and includes a select Voltage Controlled Crystal Oscillator (VCXO) and the Crystal Semiconductor 8412 input receiver. Camelot has also included the near-ubiquitous Pacific Microsonics PMD 100 HDCD (High Definition Compatible Digital) digital filter, but, unusually, offers the user access to the PMD 100's eight dither settings. Digital conversion is accomplished by four Burr Brown PCM 63P-J Collinear 20-bit D/A Converters, said to be chosen for their unmatched combination of musicality and superb technical performance in such critical areas as low-level linearity, signal-to-noise ratio, and dynamic range. The four converters are used in a "dual-differential" or "balanced" configuration, providing a true balanced output to either the internal analog section or an outboard pre-amp. The Uther v2.0 also provides an analog-domain volume control so it can be used in lieu of a line-level preamplifier. The Uther v2.0 is supplied with eight digital inputs and two digital outputs, and is available with Camelot's Royal Bloodline data bus, the latter allowing for enhanced communication with other similarly equipped Camelot Technology products, including the Dragon Pro 2 Mk.II Jitter Reducer/Resolution Enhancer.

There's little denying that the Uther is butt ugly. You want buttons? Mighty Joe Young could operate these controls! Legible LEDs? With apologies to Timbuk 3, the Uther's so bright I gotta wear shades! This last comment isn't intended in a derogatory sense. The enormous front panel LEDs are comfortably viewed from my listening position, and very useful when using the remote volume control. Besides, if bathing a CD in green light has proven to be beneficial, think of the benefits of flooding your entire listening room with it!

Sound
My, how far we've come. Five years ago, I begged, pleaded, pouted and otherwise cajoled my finance advisor (a.k.a. the wife) into letting me purchase my reference Theta DSPro Gen. III D/A converter. (I also had to promise weekly hot oil back massages. Hey, a man's gotta do…). At $5600.00 retail, this was no small feat. So, it was with great consternation that I (ear) witnessed the arrival of the new (digital) age, via the Uther v2.0. Am I questioning the purchase of the Theta? Not one bit. But such is the mark of progress that at the end of a component's shelf life, the audiophile can purchase, at half the cost, more performance than could have been had seemingly yesterday.

I believe the Uther is the first decoder, (outside the recording studio), that allows the user to access the different levels of dither available on the PMD-100 chip. At first blush, I thought this feature would be a boon to "shaping" the sound of certain less-than-pristine discs. I found, in practice, that this was not the case. During one particularly long (and magical) listening session with my wife, we decided to run through the available settings. Using a variety of discs, we observed that any level of dither other than the standard setting resulted in a slightly bright, whitish character. As I was hoping for just the opposite effect, we settled on the standard setting for the remainder of the review.

In some quarters, a transient's leading edge is believed to be the major contributor to the definition of the recorded soundspace. The Uther seems to extend this effect so that the soundstage is further defined by the continuous tone, well after the occurrence of the transient. Conventional digital has, to my ears, been like a flickering candle in a darkened room. The puff of light (transient) illuminates the room (soundstage), then dims. This repeated on/off cycle of spatial definition has, for me, always been a thorn in digital's side. With the HDCD process, (via the Uther), we now have a semblance of continuity in the portrayal of space.

Certain audio cognoscenti have criticized the HDCD process for muting transients. I cannot concur. What I do hear from the process is unetched transients, which are not presented in stark relief against the decay of the signal. My reference Theta Gen. III, by comparison, seems to add an upper frequency "spike" to transients, resulting in a slight sense of (artificial) presence. The Uther's combination of natural transients, retrieval of low level detail, and recovery of ambience information results in a more natural sense of presence than that heard from other digital products. This proved to be a major contributor to my enjoyment of the Uther. Its ability to retrieve more detail from "audiophile approved" discs, while delivering a much more palatable presentation of mass-produced (read poorly recorded) commercial discs, justified its asking price. With the Uther present, I found myself pulling out discs that I had long ago shelved due to poor quality. While the audiophile in me felt perfectly sated, the music lover positively swooned.

The final step was to utilize the Uther's integral gain stage (with remote volume control) and run its output directly into my amplifiers. I expected that the removal of the Balanced Audio Technology VK-3i would result in a significant sonic improvement. My hopes were, perhaps, a bit too high, as improvements were subtle but noticeable. A slight reduction of grain in the high frequencies, along with a touch more image palpability, was the final analysis. If you are using an all-digital system and don't need the added switching flexibility, the savings on an entry level-line preamplifier brings the cost of the Uther into bargain territory.

Long term listening did result in a couple of caveats. Using non HDCD-encoded discs, vocal sibilance could be too prominent with respect to the rest of the musical signal. I'm of the mind that this is not the result of a frequency accentuation but, rather, it is due to the elimination of other masking distortions which more clearly exposes anomalies in the recording itself. A similar observation was made while listening to HDCD-encoded discs, which exhibited a mild sheen in the upper mid/lower treble. This effect was not noxious mind you, but perceptible.

The perceptive reader may have noticed that I omitted a description of the specific musical selections used throughout the review period. Why? Because the performance gains afforded by the Camelot trio seemed to span all musical genres and recording techniques, giving no favor to one particular type of music over another. The Camelot trio did not simply "play notes" in my room. It conveyed the emotion and artistic message of every piece of music more fully than any other digital front end that has graced my reference system. What a good turntable, record cleaner and cartridge do for vinyl, the Camelot trio does for digital. Needless to say, highly recommended.

[Many thanks to Dr. Steve Fischer at Soundquest Audio, West Bloomfield, MI. for the gracious long term loan of these units.]

Merlin Pro Transport, Dragon Pro2 Mk.II Jitter Reducer/Resolution Enhancer, Uther v2.0 Mk.II Digital-to-Analog Converter
Manufactured by Camelot Technologies
30 Snowflake Road, Huntingdon Valley, Pennsylvania 19006
phone: (215) 357-8356, fax: (215) 357-7859
e-mail: camelot@camelot-tech.com, web: http://www.camelot-tech.com
Prices: US$2195.00 (Merlin Pro), US$1495.00 (Dragon Pro2 Mk.II), US$2995.00 (Uther v2.0 Mk.II)
Copyright © 1999 Audiophilia Online Magazine Home