Theta tech history continued:

Pearl, Miles, Jade, David, Voyager, Carmen, Carmen II, David II

Released in February of 1997, Pearl CD Transport was Theta’s lowest cost transport ever, yet offered a lot of the proprietary technology found in earlier, more expensive units. Based on the Pioneer Stable Table, which was an extremely stable transport mechanism, it incorporated jitter reduction circuitry, and multiple high quality power supplies.

Miles was Theta Digital’s first Compact Disc Player. First released in June of 1997, Miles was based on the Pearl’s ultra-stable transport, with the all-important additions of D to A conversion using Theta’s proprietary algorithms on a high powered computer, and an analog volume control similar to Casablanca's. The DAC was a hybrid combining the advantages of one-bit with those of 18 bit technology. Miles had excellent power supplies (four of them), Theta's jitter reduction technology, and was offered with a choice of either single ended or fully differential balanced output.

The Jade CD Transport, introduced in November of 1997, was the first Theta product to take advantage of the intensive digital signal buffering Theta calls Jitter Jail technology, since incorporated into succeeding processors and transports.

Taking advantage of the technology used in the Pearl CD transport, Jade had a massive power supply comprised of multiple high-current, low-flux transformers. Individual, highly regulated voltages were fed to all critical circuits. This separation of supplies kept each circuit noise-free and isolated from spurious signals. While not surprising to see in high-priced components, this kind of quality was not at all common in a component as reasonably priced as Jade, nor were its bi-laminate steel chassis and RFI shielding.

David DVD/CD Transport was released in April 1998. Voyager Universal Transport, which played DVD, CD, and LD discs, was introduced two months later, in June 1998. They are very much alike, except for the greater versatility of the Voyager.

DVD, as a medium, presented new challenges. The audio sampling frequencies are higher than CD’s 44.1 kHz: 48kHz and 96kHz, and the video is presented in a purely digital form, unlike laser discs, which are recorded and played back in analog format.

DVD’s disparate clock speeds (16mHz audio and 18mHz video) multiply digital noise, as they tend to interact. This noise can degrade both sound and picture, creating less than satisfying audio performance and video that is unclear, noisy and lacking three dimensionality. Theta’s proprietary Jitter Jail technology and other digital noise reduction strategies were called upon to deal with the most pervasive problems in digital signal processing.

In the audio section, high-speed CMOS logic gates used in reclocking and extensive use of ground planes prevented digital noise and hash from corrupting pure clock signal. Theta-designed low-flux transformers and high isolation power supplies fed each key area of the audio board, isolating clocks and DSP sections. The signal was output through extremely high frequency pulse transformers to the various output terminals.

The video sections were handled as meticulously as the audio: multiple transformers and high isolation power supplies separately fed critical areas of the video section, including the clocks, output circuits and main DVD decoder circuits. The motor controller and display were isolated from the rest of the circuits. Each DaViD had six transformers and fourteen highly regulated power supplies. The Voyager had seven transformers and twenty-one highly regulated power supplies.

The point of all this careful separation of audio, video, display and motor power supplies was to keep circuits from interacting, contaminating one another. Each circuit was kept as free from both digital and electromechanical noise as possible. The DVD decoder power section was then filtered again at key points to further minimize residual noise.

After the digital video signals were converted to analog signals, they were sent to individual Theta-designed video filters and extremely high-speed output buffers.

The Voyager used two separate laser head pickups. The laser used for the playback of DVD source material has a wavelength of 650nm. The second laser, for playback of CD’s and Laser Discs, has a wavelength of 780nm. This provided optimum performance for each type of source material.

Carmen DVD transport, released in January 2000, was an evolutionary step forward for DVD transports. Theta's newly designed audio and video circuits met the challenges of developments in DVD technology. Carmen was another of Theta's ongoing efforts to bring superb performance and sound quality to lower priced components.

Carmen accommodated sampling frequencies of 44.1kHz, 48kHz and 96kHz and bit rates of 16, 20 and 24.

Audio and video were processed in circuits completely separate from each other. This separation kept video noise out of the audio circuits and audio noise out of the video circuits. Carmen used discrete low-jitter crystal oscillators for video and audio frequencies: Data was then buffered; re-clocked, corrected for errors in timing and realigned before output, eliminating 'artifacts' from both audio and video. DVD and CD sound both Benefited from this scrupulousness.

Digital video signals were converted to analog, filtered and sent to extremely high-speed output buffers, for a DVD picture quality that is clear, color balanced and three-dimensional.

Carmen's multiple transformers fed fourteen highly filtered and regulated power supplies, for extreme isolation between circuits, each supply and circuit with its own integral RF suppression filter to further reduce interaction between the stages of each independent circuit, and between the audio and video sections.

Carmen's drive mechanism used twin laser diodes, 650nm for DVD and 780nm for CD, CD-R, CD-RW and VCD, minimizing errors. Low-jitter digital servo circuits controlled motor speed, laser tracking and focus.

The most noteworthy of Carmen's optional features were 4:2:2 Serial Digital Video Out and Ultrasync™ Progressive Scan (480p).

David II DVD/CD Transport, released in May 2000, might best be described as an audiophile quality CD transport and a separate videophile DVD transport that happen to share one chassis. The audio and video circuits of the unit were completely independent, and thus did not compromise one another.

David II took advantage of all of the technological advances that went into Carmen, and added features of its own.

David II used multiple analog power supplies comprised of six low-flux, Theta designed transformers -- giving extreme isolation between circuits -- and sixteen highly filtered and regulated supplies.

Like Carmen, David II had an advanced drive mechanism with twin laser diodes, 650nm for DVD and 780nm for CD, CD-R, CD-RW and VCD. David's options included 4:2:2 Serial Digital Video Out and/or Ultrasync ™ Progressive Scan (480p).

For the Carmen II DVD/CD Transport, Theta redesigned and enhanced virtually every internal component of the original Carmen, equipping Carmen II with a new DVD board and drive, new audio and video circuits, a new power supply, and a new front-panel display.

Carmen II was designed to appeal to both movie lovers and music lovers, incorporating important features and technologies, all while attempting to keep it at an affordable price.

Carmen II can handle digital audio at 44.1, 48, and 96 kHz with resolutions of 16, 20, and 24 bits. An advanced drive mechanism with twin laser diodes-650 nm for DVD and 780 nm for all CD formats-makes it compatible with just about any disc or format.

Carmen II's drive mechanism, like David II's, has low-jitter digital servo circuits to control motor speed, laser tracking and focus. It automatically selects the proper laser for the type of disc being played, enhancing read-out precision and keeping errors to a minimum. Errors introduced by fingerprints, dust and warping are corrected by parametric statistical analysis circuits.

Carmen II has a massive, shielded, 65-watt main DC power supply. It is highly filtered at both the input and output stages to keep unwanted noise from degrading the power used by the signal processing circuits. CD and DVD sections are addressed separately, with interaction between the circuits kept to a minimum.

Separate, extremely low-jitter clocks for both the CD and DVD playback dramatically reduce digital noise that can degrade sound and picture. The audio and video circuits are also isolated from each other. Multiple regulated subordinate power supplies are dedicated to each section.

Each power supply and circuit has integral RF suppression filters to prevent interaction between the stages of each independent circuit, and between the audio and video sections.

Theta's new Digital Direct Ultra-Sync II Progressive Scan System de-interlaces the video signal in the digital domain before it is converted to analog. Theta-designed discrete video filters and high-speed video amplifiers– with 108-mHz, 12-bit video digital/analog controllers – are now coupled with Faroudja Laboratories’ acclaimed DCDi™ deinterlacing technology, assuring an accurately rendered 480p picture, free from the motion artifacts inherent in the performance of players using off-the-shelf progressive scan solutions. All this is standard on Carmen II, while the Ultra-Sync System was a costly option on the earlier unit.

Theta's proprietary ultra-low jitter video re-clocking circuits and video correction software complete the picture.

A 4:2:2 Serial Digital Interface (SDI) for Video, to keep the signal in the digital domain, is available as an option. Keeping the signal in the digital domain, rather than subjecting it to further conversions to analog and back again, avoids major sources of degradation, which can be particularly noticeable in high definition video systems. The picture quality on flat-panel plasma screens and digital video projectors is particularly revealing of the performance advantages of SDI's purer digital signal. A Digital Video Interface (DVI) will be available at future date.

4:2:2 is an option on all Davids, Carmens, and Voyager transports.  

 

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