POSITIVE FEEDBACK ONLINE - ISSUE 49
ZCD-200 CD player
as reviewed by John Hoffman
Decware Audio is one of the companies that charted the course of the low-powered vacuum tube movement in the US audio scene. In the mid 1990's, Steve Deckert introduced the Zen Triode amplifier, with a mighty two watts per channel of output power.1 This amplifier became the bellwether product for the company, and has laid the foundation for a lineup of other audio products. The breadth of the product line at Decware is inspirational, to say the least. Audio hobbyists with refined tastes but limited finances can select from various tube amplifiers, browse a large high efficiency speaker line up, find a tube buffer, pick out a headphone amplifier, or even purchase a CD player with a vacuum tube output stage. In essence, the current array of products offered by Decware Audio allows a person to assemble a complete audio system that offers excellent performance, yet is modest in price.
Steve Deckert selected a TASCAM CD player as the platform for the installation of his vacuum tube output stage. The latest generation of the TASCAM player includes several upgrades that markedly improve the performance of the player. The machine utilizes the latest TEAC soft load transport, which has improved disc-handling characteristics. A new DAC chip and clock circuit is fitted to this machine; and results in significant increases in bit rate decoding and a reduction in jitter rate. The TASCAM sports a set of redesigned circuit boards, and Steve mentions that the wiring path is significantly cleaner than in earlier players. However, the cornerstone of this TASCAM machine is the overbuilt power supply, and the sturdy metal frame used in the disc transport assembly. Both of these features remain unchanged. This combination of these attributes is why the stock CD player is an ideal candidate for modification, and provides a solid platform to support the Decware tube output stage package.
The ZCD-200 CD player output stage contains a single 12AT7 tube, which is configured for single ended triode operation. This tube runs at lower voltages than one would expect, which extends its lifespan. The circuit is designed for continuous operation, and an LED light located on the player's faceplate indicates condition of the output tube. The DAC chip directly feeds the output stage, which is a significant factor in the performance of the machine.2 High quality coupling capacitors are used in the design, as well as carefully selected resistors, and ceramic tube sockets. An isolated grounding system for the output stage is incorporated into the Zen Triode. The digital circuit has a separate ground path, which is tied directly to the chassis. Steve went through seven circuit designs before deciding upon this configuration. Each circuit was carefully voiced, and an incremental improvement over the previous one. In essence, a great deal of time and effort is invested in the Decware CD player, which reflects Steve's commitment to the art of music reproduction.
The base version of the Zen Triode ZCD-200 CD player sells for $1049, although there is a series of options that can be fitted to the machine. An IEC power cord connector can be added for a cost of $60. The CD player has the capability of directly driving an amplifier due to its robust 5-volt output, so an attenuator package was designed for the machine. For $200 the customer can choose either a pair of dual mono stepped attenuators, or a single stereo version. The final upgrade for the player is tube regulation for the power supply, which is a $90 option.3 Steve feels this upgrade offers the highest return for the money, and if a person were to only select one of these, this would be it. The review sample I have has all of these options installed, which brings the final price of the player to $1399.
Decware shipped this player to me with 24 hours of playing time on it, just like any other customer would receive one. The Zen Triode went straight into my system, and got an afternoon of warm up time. Straight out of the box, the sound of the ZCD-200 is a bit flat in terms of tonal contrasts, and contained a noticeable amount of grain. My expectation for the sound quality of a fresh player was not high, so I was not disappointed. Steve recommends a 200-hour break in period, so I hit the repeat button and let the machine accrue some time on it. After four days, the Zen Triode went back into my system, and I was rewarded with a completely different presentation. I strongly recommend following the break in schedule, and do not make any judgment before the player has the minimum number of hours on it.
The Zen Triode CD player presents a remarkable combination of resolution and tonal colour that is tempered with the positive qualities of the tube output stage. Tube output stages were originally installed in CD players to deal with the harshness that early discs often contained. The euphonic presentation of these machines was never my cup of tea, so I generally avoided these players.4 The Decware CD player is not cut from the same sonic cloth, but instead combines superior low-level detail retrieval with a genteel personality. The ZCD-200 has an engaging tonal balance that inherently feels right, yet retrieves a high percentage of the nuances that are contained in a recording. One evening I spent some time listening to a disc by Tracy Sprung, and the opening track "Into Someone's Eyes" [Life and Art; Tracy Sprung Azi Productions AziZ 004] proves to be an excellent vehicle to showcase this players' capabilities. The acoustic guitar is rich and full bodied, with plenty of resonance and bloom. Even though the instrument is the equivalent of a dark strong cup of coffee, the underlying details are not overwhelmed by these dominant characteristics. The picked strings are clearly defined, and the decay pattern of the notes is neatly resolved. Sprung's vocals just sound real, which is a significant accomplishment for a player at this price point. I want to clarify this point, the Zen Triode gets to the essence of vocals, and combines a natural tonal balance with the proper texture that has the human voice has. Actually, every aspect of this song sounds sublime on the Zen Triode, but these two points were the high water mark in my system.
Historically speaking, tube electronics have earned a reputation for presenting the spatial aspects of a recording in a believable fashion. The Zen Triode certainly has this attribute, and I thoroughly enjoyed listening to music with a multi-layered soundstage. Once I pressed the play button, "Telluride" by Oracle [Oracle; Oracle RCA/Victor 09026-68063-2]5 literally billowed into to my listening room. The track opens with marsh wildlife sounds covering my listening room's front wall, while a steel stringed classical guitar is placed several feet in front of the speakers. Periodically, a wooden percussion instrument would interject itself in front of the various creatures that appeared to have taken refuge behind my speakers. Then between the speakers a choir of monks start a reverent chant, which creates a serene feel to the music. The acoustic signature of the venue that the monks are recorded in is clearly evident, and stands in contrast to the other instruments in this piece. The ZCD-200 paints an aural picture of this song, and allows me to see this composition with both my ears and my minds eye. The Zen Triode player creates a clearly defined sound stage, which is a trait that I certainly appreciate.
The Zen Triode CD player is aimed at hobbyists who value music reproduction, but are thrifty by nature. To coin an oft-used phrase, potential owners of this player are looking for "bang for the buck". Components that fall into this category often excel in many aspects of performance, but often have a set of limitations that needs to be considered. The Decware player certainly has many remarkable attributes, especially for the price point it resides in. The only issue that I could fault this player for is its ability to retrieve that final degree of detail contained in a recording. When compared to the significantly more expensive EAD transport and Kukama DAC, the ZCD-200 simply glosses over the final bit of realism provided by my reference components. Vocals on the EAD/Kukama combo gain one more degree of refinement, which adds to the illusion of a musical performance. The digital separates present the ambient detail in the recording with a higher degree of accuracy that contributes to the authenticity to the music. The Decware does not lag far behind in terms of overall performance, which is quite an accomplishment. With a price difference ratio between the two players of 4 to 1, this is squarely a win for the Zen Triode. The ZCD-200 provides a high degree of value to the customer, and I an envision it being at home in many levels of audio systems.
The IEC plug and stepped attenuator options lend themselves to a straightforward evaluation process. Being able to use different power cords with the CD player shows how sensitive the machine is to its cabling. In order to set a performance baseline, I first installed a run of the mill Belden power cord into the Zen Triode. After listening to several pieces on this configuration, I then swapped in power cords from Audio Magic and the Bolder Cable Company. The personality of the CD player changed with every power cord that was paired with it. The Audio Magic cable has admirable detail and intimacy, while the Bolder cord excels at providing a smooth and suave presentation. Clearly, the sound produced by the Zen Triode can be tailored with the careful selection of power cords. Perspective owners of this machine should plan on auditioning a few candidates before settling on a permanent power cord.
The 5-volt output voltage of the CD player is robust enough to drive a wide array of amplifiers. Many hobbyists have attempted to run the outputs of CD players into an amplifier, and have had varying degree of success. Passive pre-amps, or units using transformers for gain are essentially a variation of the "lets get rid of the preamp" theme. There are significant gains in sound quality to be had in this type of system configuration, but many CD players are not fitted with an output stage powerful enough to accomplish this. There have been many power amplifiers produced that cannot be driven by the op-amps used in most CD players.6 The tube output stage of the Zen Triode has been designed to do this, and the stepped attenuators will not compromise the sound quality of the player. My listening sessions began with the CD player connected to a Jeff Rowland Consummate pre-amplifier. One weekend I bypassed the Consummate, and ran RCA cables from the CD player straight into a Jeff Rowland Model 5 amplifier. After listening to a wide array of music, I concluded that my $5000 preamplifier has been rendered superfluous.7 There are practical limitations to this configuration, however the cost versus performance evaluation is definitely on the side of the stepped attenuator option.
Many audio enthusiasts believe that the source component charts the course for the rest of the audio system. Even the highest grade of amplifiers and speakers are not capable of recreating the information that a poor CD player fails to retrieve from a disc. With the Zen Triode CD player, Steve Deckert has shown that satisfying music reproduction is not exclusive to only the well-heeled audiophile. With a starting price of just over $1000, the ZCD-200 offers an enviable combination of performance and flexibility that should be of interest to the frugal audio hobbyist. The Decware CD player is a classic overachiever, with midrange performance that is difficult to match at this price point. The Zen Triode also casts a massive soundstage, which adds an attractive dimension to the music. Anyone looking for a high performance CD player should consider making the effort to hear this machine. Decware Audio has proven that high quality CD performance and a modest price tag are no longer mutually exclusive traits. John Hoffman
1. The Zen Triode amplifier runs either EL 84 or SV 83 output tubes. A lively debate has occurred over the years about the application of pentode output tubes versus their triode brethren. Decware has stayed the course with their tube choice, and their success has provides validation to the application of alternative single ended tube designs.
2. There is more than one tube output stage CD player on the market that positions a tube between an op-amp output device and the output jacks. In reality this is a solid state CD player that uses a tube to add a bit of flavor to the product. While these players may exhibit some tube like characteristics, it is usually at the cost of resolution and detail.
3. The voltage regulator tube is an OC2. NOS versions of the 12AT7 and OC2 tubes can be had found for a reasonable price, which makes re-tubing the ZCD-200 a modest expense.
4. I have owned the Sonic Frontiers SFCD-1, which I never could accept the influences of the output tubes on the music. The replacement player was a Sony SCD777ES, which was a superior player in my estimation. At a later date, I spent time with the Monarchy NM-24 DAC, which represented the capabilities of a tube output stage far better than the SFCD-1 did.
5. The man behind Oracle is Joe Taylor, who is well known for his studio production skills. Taylor also plays the guitars on this disc, and is responsible for synthesizer programming. The Mount Angel Abbey choir performs the chant passages on this disc.
6. This is a generalized statement; of course there are exceptions to the rule. If an amplifier has a sensitive pre-driver stage this can be accomplished. However, most output stages of CD players are not designed to have the voltage, current, and impedance characteristics needed to feed an amplifier.
7. There are certain traits that I found to be limitations in this configuration. The steps are somewhat large when using a 150-wpc amplifier. Also, the remote control option to my system is now lost, and I have grown to appreciate this feature. Finally, I lose the option of running more than one source in the system, which makes the use of my turntable problematic. Although it is hard to justify the cost of an expensive preamp in light of the $200 stepped attenuator option.
ZCD-200 CD player