With the growth of high-definition TV comes the need for interconnects capable of handling the massive amount of digital data between components. The cable of choice for this task, largely driven by the consumer electronics industry, is HDMI. Addressing the needs of both the content providers and the consumer, HDMI cables have become the new digital link that provides the vital data between source and display components. Unlike many of the older digital cables used solely for audio, HDMI cables carry both high bandwidth video and audio. HDMI was born out of the older DVI specification used for computer PC video. The latest HDMI 1.3 specification calls for significantly higher bandwidth requirements (10.2Gb/s total or 340MHz per channel) than the earlier versions due to an increase in resolution, color depth, and frame rates. As resolutions increase from 720p and 1080i to 1080p, so does the need for signal bandwidth. In addition, the HDMI specification also supports Deep Color, which allows the source to double the number of bits allocated for each color component. Additional features include support of higher frame rates (120Hz), although no one that I know has yet made use of this feature. There is also new audio support for Dolby's TrueHD and DTS-HD Master Audio standards, which offers up to eight discrete channels with superior audio quality when used with compatible audio decoders.

With all these wonderful improvements in consumer video, come the significantly higher data rate requirements. Unfortunately, many HDMI cables that might have worked fine in the past (at 720p or 1080i rates), fail to meet the performance requirements for the HDMI 1.3 standard. There are many HDMI cables available from a variety of manufacturers, yet a large number of them do not perform at the higher data rates, resulting is visible picture artifacts. To make matters worse, ceiling mounted projectors typically require long cable runs, making it difficult for installers to find a solution. The concern is real and we have seen the results in our home theater system. Several of the HDMI cables that we have used at 1080i rates, fail to perform consistently when pushed to 1080p, resulting in speckles or even loss of synchronization in some cases.

To address this problem, a company called VizionWare has launched a new breed of high performance HDMI cables for the A/V industry. Originally founded by Ken Egan (the company's current Chief Technology Officer), VizionWare has developed it's core digital technology in silicon and that has found its way into their new HDMI product line. Unlike passive HDMI cables that rely on fancy gold-plated contacts and exotic wire, VizionWare's Hi Wirez cable design takes a system level approach to the problem to increase performance. The company solves a variety of issues that plague current HDMI cable designs by leveraging from some very innovative technologies core to the company's array of patents, many of which are pending.

Conventional passive HDMI cables suffer from poor signal amplitude and phase dispersion throughout the cable, especially as the cable length increases. The result is signal attenuation which prevents the reliable transfer of data, and which ultimately affects picture quality. Active electronics in the Hi Wirez cable plays a key role in the performance margin gained by their design. HDMI/DVI signals are specified as CML (Current Mode Logic) signaling that only sinks current to one half of the true and complement differential pair at any given time. This asymmetric drive causes common mode radiation and load differences in the cable. The Hi Wirez cable design regenerates the source CML signals into a modified LVDS (Low Voltage Differential Signaling), a truly symmetrical and balanced drive. VizionWare's signal balancing and equalization techniques allow the data to be sent over longer runs with excellent data recovery at the other end of the cable. Once the data is recovered at the destination end of the cable, the data is then converted back into CML signaling for full HDMI signal compatibility. The Hi Wirez cable also implements advanced coding techniques they call Optimal Spectral Diffusion™ to reduce the spectral energy induced by horizontal and vertical (HSYNC & VSYNC) synchronizing coding symbols. This Transition Density Management improves the BER (Bit Error Rate) and reduces the probability of EMI. The result is an HDMI cable design that works well over long lengths with plenty of noise margin. The Hi Wirez HDMI cable fully supports 1080p, 1080i, 720p, 540p, 480p, and 480i resolutions and is available in 1m, 2m, 5m, 7m, 10m, 15m, and 20m lengths.

Eye-Diagram
Eye-Diagrams (also called Eye-Patterns) are a tools used by engineers to evaluate the performance of a digital signal. While a single snapshot of a waveform shows the behavior at that given time, the eye-diagram displays many samples of the signal accumulated on top of one another. The result is a picture that shows the nature of the signal being examined. The space around the light-blue mask is an indication of the noise margin. Any bad sample will show up on the display making it easier to identify problems with the interconnect. Below are some pictures taken with a high performance Tektronix TDS684 digital storage oscilloscope.

Courtesy of Ken Egan at VizionWare (Tektronix TDS6804)

Passive Cables
The waveforms shown here represent the performance characteristics of a typical passive HDMI cable. This 5-meter cable uses 24 gauge twisted-pair wires to carry the signals from one connector to the other. In this example, the eye diagram is showing signs of high level attenuation. As the eye closes around the MASK (light-blue area), data errors will begin to occur resulting in picture artifacts and/or a complete loss of signal. Due to the slow rise and fall times, jitter increases substantially as seen in the lower photo. In this example, the cable does not meet the performance requirements needed for a reliable picture, which also contributes to the small eye opening. In this example, artifacts would likely be present on the display. While passive cables lack some of the advantages of the active designs, other factors also contribute to performance degradation. Poor termination methods with impedance discontinuities and intra-pair skew (differences in electrical lengths of a pair) lead to signal reflections and jitter. In theory, cables are merely transmission lines and need to be designed as such. Unfortunately, in practice it is not always that easy to do.

Courtesy of Ken Egan at VizionWare (Tektronix TDS6804)

Active Cables
VizionWare's Hi Wirez active cable design have the following performance characteristics with a similar 5-meter length. This cable uses smaller 30 gauge twisted-pair wire, which accounts for the smaller diameter and more flexible cable construction. The top photo shows an open eye with a good amount of margin around the mask (light-blue area), which will ensure that the received data can be easily recovered. As indicated from the photos, the rise and fall times are very fast and the active equalization helps minimize the transition time. Similarly, the lower photo shows a cumulative collection of rising edge samples of the signal. The tightly controlled edge results in a signal with low jitter. Even with a much longer Hi Wirez cable (15-meters in our case), the electrical signals exhibit an open eye with minimal jitter and plenty of margin.

Setup and Performance
Our system utilizes the new Mitsubishi HC5000 Full-HD 1080p projector. The physical distance of the projector from our external video processor is around 15-meters, the exact length of our review cable. This made it a perfect test vehicle to evaluate the performance of the Hi Wirez active HDMI cable design. Our source material came from a Sony PlayStation3 (PS3), which is the first consumer product to meet the new HDMI 1.3 specification. Using the PS3 as a source, our Blu-ray movies were played in full 1080p along with some of the new video games. Other sources in our system were upconverted to 1080p using our DVDO iScan HD+ video processor. For the purposes of this review, we connected the 15-meter Hi Wirez HDMI cable directly from the PS3 to the HC5000 projector with no inline switching.

VizionWare provides an AC power adapter with the Hi Wirez HDMI cable that is designed to input power from either end of the cable, depending upon where power is most easily available. The linear power adapter (lower noise) provides 6VDC at 700mA with the center pin positive. We connected the AC adapter on the transmitting end of the cable as it was more convenient for us to get power there.

We started viewing some Blu-ray DVDs from our sample collection. Black Hawk Down and Talladega Nights were the first movies to be watched. We have only been watching 1080p for a couple of months now and it is a significant improvement over 720p. Picture quality is spectacular in full 1920 x 1080 resolution with no visible artifacts contributed by the Hi Wirez cable. That is not to say there are no artifacts in these pictures, just not anything we can say came from the cable itself. In comparison, some of our earlier HDMI cables most certainly exhibited problems when pushed into the 1080p arena. One of our longer cables produced speckles around high contrast areas while another exhibited intermittent loss of video synchronization during playback. As with many movie transfers, there are usually some subtle, yet visible artifacts that are the result of the telecine (film-to-video) process, which are usually due to compression and/or low level noise or grain in the picture. This is something we have noticed even in the early transfers of the D-Theater D-VHS tapes. The trick is to identify issues related to the cable itself. In our test, we found absolutely no problems with the Hi Wirez HDMI cable.

What really impressed us with this cable was the new PlayStation3 games, such as NBA 07 featuring full 1080p at 60 frames per second. The PS3 has incredible processing power and these games unleash vivid colors and with extremely high resolution and fast action. While I haven't been a gamer for quite a long time, it is apparent that our kids are now spoiled with the new products. We can see why HDMI 1.3 has such wonderful potential with source material that is only going to get better with time. For driving enthusiasts, there is an F-1 car racing game that makes you feel like you are really behind the wheel of a Formula-One race car. Even though the resolution of this game is limited to 720p, the realism is impressive enough to cause some motion sickness from those watching the race from the driver's seat on the 100" Stewart filmscreen.

Conclusion
Performance is essential with new HDMI 1.3 components, especially when long cables are used. Finding a long cable that performed at the higher data rates was difficult, if not impossible to find until now. VizionWare's Hi Wirez active cable approach is both innovative and highly effective in delivering the high bandwidth needed for the latest HDMI signaling requirements that are largely responsible for achieving the reference picture quality in your home theater. While the cost of the Hi Wirez cable is more than passive cables, the performance is clearly (no pun intended) superior from what we have seen. There were absolutely no image artifacts in any of our source material due to the cabling. In fact, those who saw the 1080p video in our setup were blown away with the picture quality. Even the new 1080p games with incredible action at 60 frames per second performed flawlessly on our screen. If you are tired of dealing with inconsistent and/or unreliable interconnects in your home theater, you owe it to yourself to go to the next level with VizionWare's Hi Wirez HDMI cables. It is certainly money well spent.

- Kevin Nakano

Projector: Mitsubishi HC5000 Full 1080p High-Definition LCD Projector
Screen: Stewart Filmscreen 100" FireHawk Screen on a Luxus Deluxe ScreenWall
Video Processor/Scaler: Anchor Bay Technologies DVDO iScan HD+ A/V Processor
Preamplifier/Processor: Parasound AVC-2500U THX-Ultra DTS/DD Preamp/Processor
Amplification: Parasound HCA-2205AT THX-Ultra Five Channel Amplifier
Bass Management: Miller & Kreisel BMC Mini 5.1 Bass Management Controller
Front Speakers: Miller & Kreisel S-150THX (L+R) and S-150AC (Center) Speakers
Rear Speakers: Miller & Kreisel SS-250 Tripole® Surround Speakers
Subwoofer: Two Miller & Kreisel MX-350THX MkII THX-Ultra Push-pull Subwoofers
Room Treatments: Echo Buster panels and Bass Buster towers
Set-top Box: Dish Network ViP622 HDTV Satellite and Terrestrial Receiver with HDMI
Blu-ray DVD Player: Sony PlayStation3 with HDMI 1.3
HD-DVD Player: Toshiba HD-A1 HD-DVD Player with HDMI
DVD/CD/SACD Player: Sony DVP-NS900V DVD/CD/SACD Player
DVD Audio/Video Player: Kenwood Sovereign DV-5900M 400-Disc DVD Changer
DVD Player: OPPO Digital OPDV971H DVD Player with DVI Output
D-VHS VCR: JVC HM-DH30000U D-VHS High-Definition D-Theater VCR
Media Server: Kenwood Sovereign MRH1 Entre
Remote Control: Remote Technologies Inc. T3 Controller
HDMI Video Switcher: Radiient Technologies Select-4 HDMI Video Switcher
DVI Cable: AudioQuest DV-1 20m DVI-D Cable
A/V Cables: Ultralink Platinum and Advanced Performance Series Cables

VizionWare - Hi-Wirez Digital Interconnects

Features:

• Boost higher, noise-susceptible frequencies minimizing signal loss, maintaining proper signaling levels and allowing for longer and lighter-weight cables.
• Utilize signal balancing circuit techniques to provide unsurpassed viewing clarity.
• Patented cabling technology minimizes signal coupling into shielded structures, as well as device impedance mismatches.
• Implement advanced coding techniques to reduce the considerable spectral energy induced by horizontal and vertical synchronizing coding symbols.
  
  

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  Company Information
  VizionWare Headquarters
  12708 Riata Vista Circle
  Suite A-115 Austin, Texas 78727
  Telephone: 512.493.9660
  Facsimile: 512.493.9661
  info@VizionWare.com

  MSRP: $729.99 as tested, Price varies based on length (Range: $159 - $849)
  Source: Manufacture supplied
  

  Warranty: 12-Month Manufacturers Warranty

  URL: www.vizionware.com
  Support: info@VizionWare.com