According to the NPD Group’s retail tracking service, Samsung captured the number one market share position for digital televisions in the United States in 2006. It’s also the only manufacturer to produce all four major digital television technologies; LCD, Microdisplay, Plasma, and Flat Tube.

The Samsung LN-T4642H is a 46 inch, 720p format (1366(H) x 768(V) pixels) LCD flat panel television. It has a slim, black bezel, hidden bottom speakers and is suitable to wall mount. It’s swivel stand allows +/-15° of movement providing set-up flexibility. The wide viewing angle of 178º(H) / 178º(V) combines to make it even easier.

Super Patterned-ITO Vertical Alignment (S-PVA)

Samsungs LN-T4642H display is based on its S-PVA (super patterned vertical alignment) technology. This technology is used by Samsung on its larger flat panel TVs as its alternative to twisted-nematic used by other manufacturers. S-PVA provides very wide 179 degree viewing angles due to the electrodes inside the panel being calibrated at regular intervals to adjust the alignment direction of its liquid crystal molecules.

Built-in Digital HDTV Tuner

The LN-T4642H comes with a built-in digital ATSC HDTV tuner – so a separate set-top box is not required. The Advanced Television Systems Committee (ATSC) sets the sensitivity specification for digital television and is the result of a collaboration of broadcasters, consumer electronics manufacturers, semiconductor manufacturers and other ATSC member’s recommendations.

Color, contrast ratio and resolution are important elements of picture quality. Aiming to be the best LCD TV, the Samsung LN-T4642H LCD high definition television scores well in all three areas.

Contrast Ratio

The LN-T4642H has a static contrast ratio of 1,200:1 and a dynamic contrast ratio of 7000:1 (contrast levels are adjusted on a scene by scene basis). The 7000:1 contrast ratio matches the 7,000:1 ratio achieved by the Sony BRAVIA LCD TV range and ahead of Panasonic and JVC having 3000:1 and 1,000:1 ratios respectively. Samsung don’t state if they use the more conservative ANSI test or the Full On/Full Off for contrast ratio measurement but, the contrast ratios are satisfactory in either case.

CCFL Backlight

To achieve a wider color gamut for more natural colors, Samsung, like most manufacturers, uses a CCFL (Cold Cathode Fluorescent Lamp) backlight. Most manufacturers use CCFL technology as for a comparatively low price it has a 50,000 hour average lifetime, reasonably low power consumption, high brightness efficiency and good color uniformity.

The main emerging challenger to CCFL is Light-Emitting-Diode (LED) technology which offers better power consumption, a even wider color gamut, and a mercury-free source of light (CCFLs use a small amount of mercury). CCFL manufacturers have narrowed the color gamut gap but, LEDs can provide 100+% of the NTSC (National Television Systems Committee) color standard compared to 92% coverage in the case of the LN-T4642H.

The higher cost of LED backlighting has held back manufacturers from launching products however, Samsung is going to test the water shortly with a 24-inch LCD panel with an LED backlight. The LED-backlit monitor panel has an industry-high color saturation level of 111% (of NTSC standard) compared to a saturation level of only 72% of NTSC for conventional monitors It also supports WUXGA resolution (1,920×1,200 pixels), which is the computer equivalent to Full HD resolution.

1080p High Definition

The Samsung LN-T4642H LCD television’s 720p format is one of the six Advanced Television Standards Committee (ATSC) formats for digital broadcasting considered to be HD. As well as greater image detail, high definition formats also have a couple of other advantages:

1. there is greater scope to provide image shading and
2. the pixels for larger screens do not become obtrusively large requiring an unacceptably large viewing distance.

The second advantage is the reason why manufacturers, who are constantly pushing display sizes upward, are also calling for even higher resolution formats to be added to standards. A higher resolution format, 1440p, has already popped its head above the consumer electronics horizon. It is already part of the new HDMI 1.3 specification and will probably enter the general public’s consciousness sometime in 2009.

Video Processing

Conversion of all incoming video signals to the native resolution of a particular display requires the incorporation of a video-processing chip. A secondary but, equally important, task of the video processor is the enhancement of images to remove any artifacts which may have come from resolution conversion or video transmission. As a consequence of its vital role, the video processing chip can have a dramatic effect on picture quality. It is even more important with larger displays as they will naturally magnify and image defects which may be present in lower resolution video sources. The Samsung LCDs have a 10bit video processor in line with most other manufacturers. The best way to judge performance is to view the television displaying a range of different format video sources.

Sound

The Samsung LN-T4642H has SRS Lab’s patented SRS TruSurround XT surround sound technology. TruSurround XT is a multi-channel virtualization technology which aims to produce a surround sound effect using only two speakers. It will handle up to seven (6.1) audio channels.

TruSurround XT combines three patented sound processing techniques from SRS Labs:

• Dialog Clarity: Improves intelligibility of dialog
• TruSurround: TruSurround creates multichannel signals in a way that takes advantage of the human hearing system and create a surround sound field. It carries Dolby certification.
• TruBass: TruBass enhances bass performance utilizing proprietary psychoacoustic techniques. Perception of fundamental low frequency tones is restored by dynamically augmenting harmonics.

TruSurround will produce a two channel stereo output from mono, stereo, or multichannel input signals. It is compatible with signals that been decoded by a Dolby Pro Logic or Pro Logic II decoder and signals that have been encoded to stereo with a matrix encoder (e.g. SRS Circle Surround or Dolby Pro Logic).

For more information on the equipment supplied by SRS Labs can be found on their web site.

Response Time

The response time for the big screen LN-T4642H is quoted as 8ms which falls in line with those quoted for Sony and Panasonic LCD televisions. However, the Sharp AQUOS leads the pack with a fast 4ms response time.

However, one must be careful comparing display response times as there are different ways reporting and measuring them. The most common methods are “rise-and-fall” and “gray-to-gray”. The display industry association, VESA (Video Electronics Standards Association), has a technical specification for rise-and-fall but, not for gray-to-gray. Rise-and-fall is the time taken for a pixel to change from black to white (rise) and back to black again (fall) while gray-to-gray is the time to change from one shade of gray to another. There are numerous arguments abounding about which is more relevant to assessing a displays performance and for the moment it is simply worth being aware that like is being compared with like.

Useful Functionalities

The Samsung LN-T4642H has a number of useful features including:

• Picture-in-Picture (PIP): for simultaneous viewing
• Clock on/off timer: set the time for your TV to start and shut down
• V-Chip System: allows parents to block objectionable content
• Multi-lingual on-screen displays: English, Spanish and French
• Variable sleep timer: turns your TV off after a set time
• Auto volume leveler: keeps the same audio volume across channel changes

Connections

The LN-T4642H has a good range of connections including three HDMI (High Definition Multimedia Interface) and a PC (RGB) input. A full connection list is provided in the specification at the end of this review.

Samsung provides mounting holes at the back of its LCD TVs which are based on VESA (Video Electronics Standards Association) standards.

Warranty

Samsungs LCD, high definition televisions are backed by with a fairly standard 12 month warranty.

Comparison Samsung LN-T4642H LCD TV vs

Apart from the different high definition resolution of 720p vs 1080p the other major differences between the Samsung LN-TXXXXH and the Samsung LN-SXXXXD models are:

• a slightly higher contrast ratio of 7000:1 contrast ratio vs 6,000:1
• no DCR tuner or CableCARD slot
• a third HDMI interface compared to 2 and
• no USB connection

1080p high definition TVs of a similar size produced by Samsung include the 52 inch LN-S5296D and the 46 inch LN-S4696D. Larger name brand competitors with the Samsung LCD TV range include Sharp’s AQUOS range and Sony’s BRAVIA range.

Further Reading

Ptek has recently reviewed similar size LCD televisions including the Sony Bravia XBR 52 Inch KDL-52XBR2 LCD HDTV and the Sharp AQUOS 42 inch 1080p LC-42D62U LCD TV.

Presentation Technology Reviews recently looked at newcomer NuVision’s 42 inch 1080p LCD television.

Specification Samsung LN-T4642H LCD TV