Frequently Asked Questions

HD (high definition) is the latest in a long line of major improvements in television technology, which has moved from black-and-white analogue to widescreen colour over the last 50 years. HD gives you exceptionally clear, crisp pictures with vivid colours and up to five times more detail than standard definition.

Blu-ray, also known as Blu-ray Disc (BD), is the name of a next-generation optical disc format jointly developed by the Blu-ray Disc Association (BDA), a group of the world's leading consumer electronics, personal computer and media manufacturers (including Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson). The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data. The format offers more than five times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc. This extra capacity combined with the use of advanced video and audio codecs will offer consumers an unprecedented HD experience.

Dolby Digital, or AC-3, is the common version containing up to six discrete channels of sound. The most elaborate mode in common usage involves five channels for normal-range speakers (20 Hz – 20,000 Hz) (right front, center, left front, right rear and left rear) and one channel (20 Hz – 120 Hz allotted audio) for the subwoofer driven low-frequency effects. Mono and stereo modes are also supported. AC-3 supports audio sample-rates up to 48 kHz.

The Cinema Version of "Dolby Digital EX" is called Dolby Digital Surround Ex and works the same way. Dolby Digital Surround EX was co-developed by Dolby and Lucasfilm THX in time for the release in May 1999 of Star Wars Episode I: The Phantom Menace. It provides an economical and backwards-compatible means for 5.1 soundtracks to carry a sixth, center back surround channel for improved localization of effects. The extra surround channel is matrix encoded onto the discrete Left Surround and Right Surround channels of the 5.1 mix, much like the front center channel on Dolby Surround encoded stereo soundtracks. The result can be played without loss of information on standard 5.1 systems, or played in 6.1 or 7.1 on systems equipped with Surround EX decoding and additional speakers. Dolby Digital Surround EX has since been used for the Star Wars prequels on the DVD versions and also the remastered original Star Wars trilogy. A number of DVDs have Dolby Digital Surround EX audio option.

In the consumer (home theater) market, AC-3 and DTS are close in terms of audio performance. When the DTS audio track is encoded at its highest legal bitrate (1,536 kbit/s), technical experts rank DTS as perceptually transparent for most audio program material (i.e., indistinguishable to the uncoded source in a double blind test). Dolby claims its competing AC-3 codec achieves similar transparency at its highest coded bitrate (640 kbit/s). However, in program material available to home consumers (DVD, broadcast, and subscription digital TV), neither AC-3 nor DTS run at their highest allowed bitrate. DVD and broadcast (ATSC) HDTV cap AC-3 bitrate at 448 kbit/s. But even at that rate, consumer audio gear already enjoys better audio performance than theatrical (35 mm movie) installations, which are limited to even lower bitrates. When DTS audio was introduced to the DVD specification, studios authored DVD movies at DTS' full bitrate (1,536 kbit/s). Later, movie titles were almost always encoded at a reduced bitrate of 768 kbit/s, ostensibly to increase the number of audio tracks on the movie disc. At this reduced rate (768 kbit/s), DTS no longer retains audio transparency.

AC-3 and DTS are sometimes judged by their encoded bitrates. DTS proponents claim that the extra bits give higher fidelity and more dynamic range, providing a richer and more lifelike sound. But no conclusion can be drawn from their respective bitrates, as each codec relies on different coding tools and syntax to compress audio.

DTS-ES (DTS Extended Surround) includes two variants, DTS-ES Matrix and DTS-ES Discrete 6.1, depending on how the sound was originally mastered and stored. DTS-ES Discrete provides 6.1 discrete channels, with a discretely recorded (nonmatrixed) center-surround channel; in home theater systems with a 7.1 configuration, the two rear-center speakers play in mono. DTS-ES Matrix provides 5.1 discrete channels, with a matrixed center-surround audio channel. DTS-ES commonly works on a matrix system, whereby processors that are compatible with the ES codec look for and recognize "flags" built into the audio coding and "unfold" the rear-center sound from data that would otherwise be sent to rear surround speakers. This is notated as DTS-ES 5.1. Less frequently, DTS-ES data can be encoded with a discrete sixth audio channel (the rear-center), meaning that the audio data for the sixth channel is stored separately from the other information and is not embedded or matrixed among other channels. This is notated as DTS-ES 6.1, as the center-rear is completely discrete from the other channels. ES-capable processors can recognize the discrete sixth channel and play it back if connected to the necessary speaker(s). In contrast, Dolby's competing EX codec, which also boasts a center rear channel, can only handle matrixed data and does not support a discrete sixth channel. DTS-ES is backward-compatible with standard DTS setups, so with non-ES equipment that does not recognize the flags or with ES-enabled equipment that lacks the extra speaker connections, sound plays back in 5.1 as if it were standard DTS. Only a few DVD titles have been released with DTS-ES Discrete. Note: The center-rear/surround channel is encoded and decoded in exactly the same way as the center-front. The center surround channel can be decoded using any surround sound processor by feeding the left and right surround signals to the processor inputs. Left-Center-Right surround is produced. This will work for a "center surround" reproduction, whether the source material is explicitly encoded, as in DTS-ES, or hidden as ambience in any 5.1 source, including DTS-ES 5.1 and Dolby 5.1.

Tuff Systems aren't Sky or Cable suppliers. However, in all our wiring diagrams we take care of the provision for Sky or Cable feeds. In all properties that Tuff Systems wiring diagrams are implemented, you will be able to house between 1 -16 Sky boxes or as many Cable boxes as your provider allows. Furthermore, we will meet your chosen provider on the day of installation to make sure everything runs smoothly.