If you don't know your woofers from your tweeters, or you're baffled by technology, let us help you out! This handy jargon buster has been designed to demystify some of the most common hi-fi and home cinema terms. We've tried to explain some of the more exotic functions and facilities you might encounter on this site in layman's terms. We hope you'll find it useful.
This is the highest of the high, so to speak, being the best quality
High Definition standard. Also known as ‘True HD’ or
‘Full HD’. Blu-ray and HD DVD discs offer such pretty
pictures, although not all screens can accept them. The number
‘1080’ represents the 1,080 lines of vertical resolution,
progressively scanned (see entry). The term usually assumes a
widescreen aspect ratio of 16:9, implying a horizontal resolution of
1920 pixels. This creates a frame resolution of 1920×1080, or
2,073,600 pixels in total.
4K is the most common of an array of enhanced resolutions far higher than the 1080p we're used to watching. 4K is so named because it has approximately 4000 pixels across (the exact number varies depending upon which camera the director chooses, but in the home you get 3840). The format gives approximately four times more resolution overall than 1080p. Much like when HD TVs first hit the market, there's not an awful lot of ways you can get 4K into your new set should you buy one, but this is all set to change over the next year or so.
(Advanced Audio Coding)
A popular digital audio encoding system that compresses data files for
greater storage capacity – think of the music tracks stored on an
iPod and you’re on the right track. AAC is similar to MP3, but
offers superior quality and DRM support. AAC is the preferred coding
system of Apple, so, for example, you’ll find tracks on iTunes
encoded this way. A typical files size is 4MB.
One of the two ways that televisions create a 3D picture. Active 3D uses a process known as Alternate Frame Sequencing. The TV creates two images (one for the left eye, and one for the right) and flicker rapidly between the two. The glasses for this type of television are usually battery-powered and have shutters that open and close in coordination with the two images on the TV. Because this happens faster than the human eye can detect, the brain perceives a complete, three-dimensional image.
AirPlay enables you to send photos, videos or, most commonly, music wirelessly, straight from your iPhone, iPod Touch, iPad or compatible PC/Mac running iTunes. We sell a huge variety of audio equipment that's compatible with AirPlay audio, where you just tap an icon on your Apple device and it gets beamed through the air. For the photo and video capabilities, take a look at the Apple TV, which connects to your TV via HDMI.
Pretty much does what it says on the tin. In hi-fi terms this is an
electronic device that amplifies or boosts the signal from a source
component to a required volume. Also see Pre-amplifier and Power
For hi-fi buffs this refers to a way of recording and its related
playback. So analogue should bring to mind images of turntables and
tape recorders (and men with long beards) as opposed to portable MP3
devices, compact disc and DVDs. An analogue recording is one where the
original audio signal and its corresponding waveform are modulated onto
a physical media or substrate, such as the groove of a record. A
physical quality in the medium (e.g. the shape of a record groove) is
directly related or analogous – geddit – to the physical
properties of the original sound's waveform. See Digital.
Analogue TV tuner
With the digital switchover now complete, you might wonder why analogue tuners are still on this list. Although you won't pick anything up through an aerial from one of these, they are still sometimes used for systems like the Sky Magic Eye, which allow you to watch your Sky box in another room.
You may have heard the name cited as evidence during a heated debate between iOS and Android fans, since AptX has long been giving the little green ‘bot a reason to grin. AptX is an Audio codec for storing and sending compressed information wirelessly between devices. It’s most commonly used for Bluetooth-ing music to a compatible speaker or dock. It provides the best bandwidth for sending media to a compatible receiver, meaning when you stream music from your phone, you can enjoy the best possible sound quality and all with zero wires!
The displayed width of an image divided by its height. A bit too much like maths? Okay, this is to do with the shape of the picture. Chances are, at some point, you've noticed black bars either along the sides or the top and bottom of your TV screen. This is because whatever you're watching has been made in a different aspect ratio. Nearly all TV shows since the mid 2000s have been made in the 16:9 'widescreen' format that's the same shape as your TV. Since the advent of colour film, a lot of movies were made in this shape too. However, older TV shows and most black and white movies are in the square-ish '4:3' aspect ratio. Most movies use a much wider image for a more epic appearance, which you may hear referred to as 21:9 or 2.35:1. To fit these different ratios onto your 16:9 TV you can either stretch them, which can distort the image, zoom in, which cuts off the edges, or display black bars in the blank spaces. The majority of TVs let you choose which you prefer from these options.
AV Receiver (Also known as AVR)
Think of this as the heart of your surround-sound system. The term “receiver” refers to the fact that it has a built-in radio tuner – but it’s much more than that! Capable of receiving signals from a variety of sources such as DVD or Blu-ray players, the receiver decodes the surround sound information and amplifies it to the speakers, while passing the video signal on to the television. There are various audio formats such as Dolby and DTS which deliver different results, but they all make for top-notch surround sound. You can also connect audio sources, such as iPods/mp3 players, and many now offer wireless music streaming to cover all your home entertainment needs.
How low can you go! Sorry. This is the lowest part of the frequency
range, which is reproduced by woofers and subwoofers in loudspeakers.
The scary rumbling often heard in home cinema demonstrations is a
classic example of extreme bass.
A simple and cost effective way to improve the sound of your system or
simply a complex version of the Emperor’s New Clothes: the jury
is always out on this one. Bi-wiring is essentially a bewildering way
of connecting speakers to amps, which is said to improve sound quality.
The technique makes use of the two sets of speaker terminals commonly
found on the rear of loudspeakers, and keeps high notes separate from
mid/bass frequencies in the cable runs. This is meant to keep the
respective frequency signals cleaner as they don’t mix with each
Bit and bit rate
Bit rate is effectively a measure of quality of a digitised audio or visual signal. Measured in kbps or mbps (kilobits per second or megabits per second; a megabit is 1024 kilobits), it's telling you how much data is used every second. A higher number means better fidelity, as the digital description of the sound or picture is more detailed. Bear in mind, though, that this comes at the price of a larger file size. When people talk about 'bit depth' (e.g. 24bit audio or 10bit colour) this refers to the range of data that can be described by the file. 24bit audio, for example, is able to produce more subtle changes in volume than the 16bit standard, and higher bit colour can show a greater range of shades between primary colours. .
Blu-ray disc (BD)
They look like DVDs, but they're a whole lot better. Blu-ray discs are currently the best quality way to watch movies in your own home. Not only do they offer amazing quality high definition picture, but you’ll also enjoy better sound quality than DVDs or HD movies streamed from the web. Another advantage over downloads is access to special features, which can include information appearing over the top of the movie image: pretty cool for film buffs! New releases tend to cost only a pound or two more than DVDs and all Blu-ray players will play your existing DVD collection too. A no-brainer for film and TV fans.
Named after the ancient Nordic king Harald “Bluetooth” Gormsson (seriously!), this wireless media standard facilitates the transfer of data between compatible devices. Most commonly it is used in smartphones or tablets to play music through a speaker system of some kind. The capability is built-in to a huge range of audio devices from hi-fi systems to soundbars with minuscule units also available to add-on to existing systems.
This is the amount of light that is emitted from any screen or
projector and perceived by the eye. Brightness of screens is measured
in cd/m squared, while for projectors it is measured in ANSI (American
National Standards Institute) lumens. For both, the brighter the model
the higher the rating. Remember, as with power in an amplifier, the
biggest number doesn’t always equate to the best performance.
Equally, if a TV cannot deliver a bright image, you’ll need a
dark room, and this isn’t always possible.
When saved as raw data, audio files take up a lot of space and video an astronomical amount. The cameras used to film The Hobbit, for example, use up to 5GB a minute! Therefore the files need to be squeezed down, or compressed, somehow. A codec is basically a specific way of compressing a file so that it's a lot easier to manage. However, each codec is like a different language, and whatever's playing it back needs to speak the language too. This isn't as much of a problem as it used to be; Smart TVs, Blu-ray players and other components tend to be compatible with lots of different codecs. That said, if you are interested in playing back videos from a USB drive or similar, it's worth checking compatibility.
The more colours a screen can produce, the more natural the image will
appear. Plasma screens create colours by combining red, green and blue
light. LCD screens create colours by removing colours from white
backlight. Plasma’s additive process tends to work better,
producing 90 per cent of the available colour spectrum, compared to
around 75 per cent for LCD screens.
The highest quality analogue video connection available. It's been completely overtaken by HDMI, with many units now offering no alternative to this ubiquitous new connection. However, if you have a particularly good older DVD player, or a games console like the Nintendo Wii or Sony PlayStation 2, it's still worth hunting down a component cable and using this input on your TV.
This is the difference between the lightest and darkest content that a screen or projector is capable of producing. A high contrast ratio is a desired spec for any display; being able to display a deep black alongside a bright white is what makes images appear punchy. However, due to various methods of measurements, remarkably different measured values can sometimes produce similar results. Some manufacturers no longer list contrast ratios, as claimed figures were becoming almost comically high. In typical viewing situations the contrast ratio is significantly lower than these claims, making it harder to distinguish between different devices with very high contrast ratios. The best solution is to visit our stores, if you can, and have a look with your own eyes.
The part of a loudspeaker that splits the incoming audio signal into
separate frequency bands, and then sends these signals to specific
drivers, such as the tweeter or woofer. They have a huge influence over
the final sound of a loudspeaker design.
Digital Audio Broadcasting. Digital radio transmission gives a greater selection of radio stations, and wonderful ease of access. What’s more it allows the broadcast of information like the title of the current track or programme. Some products are compatible with DAB+ which offers higher quality audio. This system isn't yet used in the UK, but you'd be covered if we did ever change. An alternative is Internet radio (see below), which offers many of the same benefits as DAB.
Standalone digital-to-analogue converters (DACs) like the Cambridge Audio DacMagic Plus squeeze the maximum sound quality from digital music (including CDs, streamed tracks and more). Digital files played through a decent DAC will achieve significantly superior levels of detail compared to the cheap DAC chips built into most digital kit. To give a brief explanation of how they work; all sound in the "real world" exists as a constantly changing wave of energy. Audio in the digital world is a snap shot of a large number of these changes (usually 44,100 a second), which then has to be converted back to a constantly changing wave before it comes out of your speakers. Quite simply, a better DAC will make sure the wave at the end is as close as possible to the wave at the start. Why not pop in for a demo and hear the difference for yourself?
Digital-to-Analogue Converter. A bit like a mini computer. DACs are at
the beginning of the signal chain, which makes them very important to
system performance. Video signals from a digital source, such as a DVD
player, must be converted to analogue form if they are to be displayed
on an analogue monitor. All new flat screens incorporate either a DVi
or HDMI connection, bypassing these devices and sending the signal
directly to the screen.
Any system that represents analogue signals as streams of numerically
encoded data. Think of all those green bits in the Matrix. Digital
systems use individual values (often electrical voltages) representing
numbers for input, processing, transmission, storage, or display,
rather than a continuous spectrum of values, as in an analogue system.
These days all TVs have a digital aerial tuner, nearly always referred to as a Freeview tuner. Some sets can also pick up free digital satellite broadcasts via a Freesat tuner.
How big is yours? Where possible, we try to include dimensions of a component both including and excluding any stand, bracket or feet it may come with. For accuracy, we always use millimetres in our measurements. Make sure to check you can fit your chosen items in!
DivX is a brand name for products created by DivX Inc., which have become popular due to their ability to compress lengthy video segments into small sizes while maintaining decent video quality. It is commonly associated with burning or ripping audio or video material onto a hard disk. As HD has become more popular, DivX has become less common, but it's still compatible with a wide range of devices.
See entry for "UPnP".
The most commonly used type of projector available; the lamp shines a beam through a spinning colour wheel of red blue and green onto a chip covering over 2 million tiny mirrors. Each mirror represents one pixel, and is capable of pivoting towards or away from the light depending on how much brightness or colour is needed – they can do this at up to 5,000 times per second! This minuscule mosaic of colours and shades is our picture, which is then sent through a lens and onto the screen. More sophisticated DLP systems use 3 chips, each with their own colour wheel; the light is then recombined using a prism before being sent to the screen.
This is the technology that puts the cinema into 'home cinema'. When a bullet whizzes across your front room, thank Dolby. Essentially it is a digital audio format that delivers surround sound replay, via a 5.1 speaker system. It's the most common format for surround sound in the home. Nearly all DVDs use it, as well as many HDTV broadcasts and online streaming services such as Netflix.
Dolby Digital EX takes the Dolby Digital 5.1-channel setup one step further with an additional centre surround channel (reproduced through one or two speakers) for extra dimensional detail and an enveloping surround sound effect. It was used on very few DVDs and has now been superseded on Blu-ray by the 7.1 capabilities of Dolby TrueHD.
Dolby Pro Logic was the foundation for multichannel home cinema, being the consumer version of the original Dolby Surround multichannel analogue film sound format. Originally, it was a way of fitting the signal for a rear speaker into standard stereo sound. While that function still works perfectly, its most common use today is making use of all the speakers in your set-up even when what you're watching is not in surround.
Pro Logic II, Dolby Pro Logic IIx
and Dolby Pro Logic IIz
Since its original release, Pro Logic has been improved with the release of Pro Logic II, which turns a properly encoded two channel source into a full blown 5 channel signal. Other improvements include better channel separation and full bandwidth, stereo signal to the rear speakers. The IIx version offers 6.1 or 7.1 channel playback. This is taken further still with IIz. It expands a 5.1 signal to 7.1 or even 9.1 with front height speakers.
Dolby TrueHD is a lossless audio format commonly found on Blu-ray discs. This gives equivalent quality to what the engineers would have heard when mixing the soundtrack in the studio, at a sample rate of up to 192 kHz, as opposed to the 48 kHz maximum of regular Dolby Digital. This isn't possible on a DVD as there simply isn't enough room on the disc. For those who’ve invested in an extra pair of rear speakers, it also supports 7.1. There was a time when only a handful of Blu-ray players and AV receivers were compatible, but it's now reached near ubiquity. That said, it's still worth double checking if you're interested in the ultimate sound quality.
A driver is a specific word that describes the individual cones within a speaker. For example, a two-way speaker features two drivers, one for the high frequencies (known as a tweeter) and one for the mid-range and low frequencies (known as a woofer or mid/bass driver). There are different types of driver, but ultimately they all vibrate to create sound waves.
Another multi-channel decoding format, similar to Dolby Digital, that delivers surround sound in the home. It's often felt to have a slight edge over Dolby in terms of performance, thanks to a bit rate that's up to four times higher. DTS was once a luxury feature, with only the upper echelons of home cinema offering support for the standard. This is far from the case now, with DTS support available on nearly all home cinema equipment.
DTS-HD Master Audio
DTS-HD Master Audio is the DTS version of Dolby True HD, making use of Blu-ray's extra storage space to offer audio that's identical to the studio master. It can also support higher sample rates, bit depths and 7.1 channel surround sound. The vast majority of current AV gear is compatible.
Players that can play both Blu-ray and HD DVD discs. So far
these haven't quite been the Holy Grail they sound like, due to some
limitations replaying one or both formats.
DVD-Audio is an extremely high quality format which uses a DVD’s superior storage capacity to offer sonic improvements over conventional CDs. Not only can it deliver stereo at 24-bit/192kHz quality, but also surround sound recordings in 24-bit/96kHz. Sadly, it never really caught on and there is extremely limited software availability, with some releases fetching collector's prices. These days, Pure Audio on Blu-ray tends to be the high resolution audio disc of choice.
If you want to copy TV programmes or home movies onto a physical disc, a DVD recorder is your best option. Dedicated disc recorders are rarely available these days, but the functionality is regularly found in more advanced machines that can also record to a hard disk drive.
Digital Visual Interface (DVI) is a video connection with a large rectangular connector that was commonly used by HDTVs and Projectors, but was quickly phased out as HDMI gained popularity. Unlike HDMI, DVI only carries picture information, no sound or other data. If you're buying all new equipment you needn't worry, but DVI to HDMI cables are readily available should you find yourself in need of one.
The dynamics of a system refers to its reproduction of the quietest and loudest parts of a piece of music. The difference between these is referred to as ‘dynamic range’. A highly dynamic system is desirable as it will be able to go from extremely quiet to extremely loud as swiftly and easily as Lewis Hamilton, and also express far more subtle changes in volume. You may come across people complaining about a recording having poor dynamic range, saying that it is "overly compressed". This basically means that, even if you have a very dynamic system, the recording makes it sound otherwise. It's perhaps best not to bring up this issue with any audiophile friends unless you're prepared for a lengthy rant!
EPG (Electronic Programme
With Digital TV now ubiquitous, everyone has access to an EPG, though you may not know that's what it's called! It's the technical term for the TV guide you can bring up on-screen to look through what's on across all channels.
If you've got an aerial for watching TV, Freeview is what you’ll pick up. As well as offering a wide selection of subscription-free TV and radio channels, there are also some that you can unlock with a subscription, without needing a new box. For those with a satellite dish, Freesat is your option if you want to avoid monthly costs.
As well as offering 50 HD channels, Freeview also offers, at time of writing, up to 10 channels in incredible HD quality, still completely subscription-free. If you want to receive these you'll need to check that the TV or recorder you're buying is Freeview HD compatible, though the vast majority now are.
Like any other wave, sound waves have a frequency, or how many times they repeat every second, measured in Hertz (Hz). The human ear can hear sounds from 20Hz to 20,000Hz (20 kHz). Low sounds, or bass, come in at the bottom and high sounds (treble) live at the top, with the space between referred to as the mid-range. Speakers and headphones usually list a frequency range in their specification, which gives you some indication as to the performance, though a demo will tell you much more about how they sound.
Ever put a CD into a computer and wondered how it knew what album it was and the track titles? The answer is most likely the Gracenote CDDB (CD Database), a massive online archive that's constantly updated by users. As well as being used by music software like iTunes, it's also built-in to most music servers.
An internal disc, such as those found in a computer, that stores large
amounts of data. Typically such designs are capable of storing many
gigabytes (GB) of data. Now a regular feature of MP3 players, DVD
recorders and DVRs.
(hard drive/disk) recorders
A component that can record to its own internal space without requiring discs or tapes so you don't have to hunt for free space on a disc whenever you want to record something. You get other advantages too, like being able to easily edit out ad breaks, for example. One popular specific type of HDD recorder for recording TV broadcasts is the PVR (Personal Video Recorder) – see below.
At its most basic level, HD means better quality pictures. It is both a broadcast and a screen technology, and there are three signal types: 720p, 1080i and 1080p. Any screen implementing these standards is called ‘HD ready’. However, to aficionados, 1080p, which is sometimes called Full HD, is considered the only ‘true’ HD standard. That said, now gaining popularity is Ultra HD (4K), which offers resolutions four times higher than 1080p!
High Definition Audio (HDA)
High Resolution Audio provides exception sound quality from High Resolution music files. Typically these are DSD, WAV, AIFF, FLAC or ALAC files at 24 bit/96kHz or 24 bit/192kHz rates. Think of it like High Definition TV for your audio and the difference is easy to hear.
The second format (with the other being Blu-ray Disc) that sought to
take over from DVD. Lost out in the battle against Blu-ray and was only ever used by a handful of companies, mainly Toshiba.
HDCP (High-bandwidth Digital
This system is designed to prevent unauthorised copying of data. In the early days of HD some legitimate equipment wasn't compatible and caused issues, but this is no longer an issue. Put simply, as long as you're not trying to breach copyright, you won't have any problems.
HDMI (High Definition
The digital successor to SCART, a single HDMI cable can carry high definition pictures, surround sound audio and remote control info between two devices. Nearly any video source you buy now has an HDMI output, from TV set-top boxes to games consoles to Blu-ray players and even laptops and cameras. Remember to make sure that you have enough inputs on your TV or AVR to connect all of your sources.
HDMI 2.0 is an enhanced version of HDMI using the same connections but offering many technical advantages. These include the ability to handle 50/60 frames per second from 4K signals, 18-bit colour, 32 channel surround sound, full 21:9 aspect support plus much more.
A badge to denote screens that can accept and display 720p/1080i High Definition pictures. Over time this term has come to mean a TV with a lower resolution than the now standard "1080p" (which is often referred to as 'Full HD'). Common on smaller screens and some budget models, you'll still see a big improvement from 720p/1080i HD pictures with these screens, though you won't see every last detail from sources such as Blu-ray (1080p) discs.
No, it doesn’t involve selling popcorn to strangers off of the street! Home cinema has come to be a catch-all term for a system that plays music and movies with a TV or projector and an external speaker system of some kind, usually surround sound. The whole idea is to recreate as accurately as possible the picture and sound quality of a cinema auditorium. Filmmakers want their work to be showcased in all its glory, with not a line of dialogue missed or a pixel out of place and a home cinema is just the tool for the job – in fact, you’d be surprised at how easy it is to build a seriously impressive sounding system.
This is the load a speaker brings to bear on an amplifier or its electrical resistance, measured in ohms. The higher the impedance – with 8 ohms being the norm – the easier the speaker is to drive or power, meaning the speaker should still work well with less power. If a speaker has consistently low impedance – say 4 ohms – the speaker is much harder to drive. It's important to make sure your speaker’s impedance is above the minimum specified by your amplifier.
The design of any audio amplifier is made up of two main sections, the pre-amplifier and the power amplifier. The pre takes care of choosing your source, setting the volume and any other adjustments such as bass and treble controls. The power amp is the bit that makes it loud! High end set-ups commonly use separate pre and power amp units, but most of the time both bits are in one box. This is known as an integrated amplifier.
In its truest form, this is simply a device that allows you to stream radio stations through the Internet by connecting to your home network. Because the device is connected directly to the web, it doesn’t rely on localised radio signals to pick up stations - instead you get access to thousands of radio stations from all over the world. Also, because an Internet connection has better bandwidth, sound quality and signal reliability tend to be better than digital radio (subject to the codec and bit rate used).
LCD TVs are currently the most popular display technology. They are made up of a film of crystals that twist to let through the right colour from the white backlight that sits behind them. This backlight was traditionally a fluorescent lamp, but now is more usually made up of energy-efficient LEDs. A set using these is usually known as an LED TV, although the core technology is the same as fluorescent lamp models.
One of the oldest, and generally the cheapest form of digital projector; creates an image by breaking a beam of light into its 3 primary hues before shining each one through a tiny LCD screen that displays the picture. The 3 hues are then recombined inside a prism before being beamed onto your screen.
LCoS stands for Liquid Crystal over Silicone. The light from the lamp is split into red, green and blue. The colours are then shone onto micro-devices, which contain liquid crystals atop a reflective surface. When an electric charge is administered, the liquid crystals alter their shape, and act like filters that control how much light hits the reflective surface according to desired brightness or contrast. The complete image is then recombined and projected onto the screen.
LED TV is actually just a development of the conventional sleek LCD flat screens we all know and love. LED TVs are basically LCD TVs with one significant difference - they use Light Emitting Diodes (LED) to backlight the screen.
or line input
A component or analogue connection operating at 'line' voltage. If a device has a line input it typically means that it is capable of either amplifying or recording from an audio source. A pair of white and red RCA plugs or a 3.5mm mini jack is the most common form of connection.
Used in many applications including the preservation of important documents, lossless compression ensures perfect recreation of stored data. For all you audiophiles out there, it means you get to rip your favourite tracks to your computer without it lopping bits out of them to preserve storage space. When these files (often known as FLAC or Apple Lossless files depending on which operating system you use) are played back, they retain every bit of their original detail – music to our ears!
This handy bit of technological hocus-pocus lets you send content between compatible devices, without the need for cables. Miracast can support 1080p video with 5.1 surround sound, meaning its most common use is to stream content from a phone or tablet to a television. It also works from Wi-Fi direct, meaning the signal travels directly between devices rather than having to go through a wireless router.
The middle of the frequency range, that sits between the bass and
treble. The midrange handles most instruments and the human voice, so
is of particular importance to musical replay. Many hi-fi components
focus on accurate replay of the midrange at the expense of the rest of
the frequency range.
Motion Processing - Refresh Rate
The standard refresh rate on TVs sold within the UK is 50Hz. This is the number of times a second the picture is "drawn". Higher quality TVs later increased this figure to 100Hz and then 200Hz. The higher the refresh rate the less flicker you'll notice and the picture should be more "solid" in appearance.
More recently, manufacturers have begun using their own measurement systems of motion processing and can't necessarily be compared between brands. Examples include LG - Motion Clarity Index (MCI), Samsung - Clear Motion rate (CMR), Philips - Perfect Motion Rate (PMR), Sony - Motionflow XR and Panasonic - Intelligent Frame Creation (IFC). All these figures are twice or more of the traditional 100Hz/200Hz refresh rate figures. Higher figures should equate to smoother motion but remember to stick to individual manufacturers if you want to compare like with like. Plasmas generally use a 600Hz sub-field refresh rate.
coil, moving magnet
Types of phono cartridge. Remember, those things that sit in the groove
of a record to pick up the sound. Sometimes called a stylus. Moving
coil cartridges generally require a special phono stage and are the
An external hard drive with a twist! NAS stands for “Network Attached Storage” meaning that once you plug your NAS drive into your wireless router, you can fill it with music, movies, even photos and important documents. All of these can then be easily accessed by any other devices operating on the same internet connection – so you can back up all your favourite media, and still get your hands on it without even switching on your computer – ideal for anyone with a wireless streaming system.
One of the newest additions to the world of hi-fi separates, a network streamer piggybacks onto your router in order to give you access to a variety of internet-based services. For example, should you have any music stored on your home PC or on a NAS drive; the network streamer can sniff it out and play it through your hi-fi, all at the touch of a button. Depending on the model, you may also get streaming services like Spotify that, with a subscription, will give you unlimited access to a library of music that you can listen to whenever you like. Add an internet radio service into all that and you’ve got a massive mine of musical multiplicity!
NFC stands for Near Field Communication. This allows close proximity transfer of media simply by holding your tablet or smartphone next to the device.
The measurement of electrical resistance, in hi-fi this is used to
measure the impedance of a speaker.
A technique invented by audio boffins and used in some specialist DACs to improve the quality of audio replay. In essence it means generating more pieces of information – or bits - from a waveform that has already been recorded. Very clever.
PAL / NTSC
PAL was the analogue broadcast system used in the UK, mainland Europe and 120 countries around the world, which runs at 50Hz. NTSC was used by the rest of the world, including North America and Japan; this runs at 60Hz. While these different frame rates are still used, the arrival of digital TV means these terms are now of little relevance as any HD Ready or better TV can accept both 50Hz and 60Hz signals.
In a hi-fi context, active means that a unit has a built-in amplifier, whereas the passive equivalent would require separate amplification. The most common example is an active subwoofer as they benefit from amplification specialised to bass, though you can also buy pairs of active speakers.
Passive 3D uses the same glasses as the majority of cinemas, giving them an instant advantage over active sets as, if you've ever seen a 3D flick, you've probably got some specs lying around. They also produce a more comfortable, flicker-free image. The trade-off is that the image in 3D is lower resolution than the active system; however, many people do still prefer it. The only way to know for sure is to pop in-store and have a peek.
If you want to connect your computer to a TV, you need to make sure it has the right connections. Most TVs have a PC input, but this term is used to specifically refer to the 15-pin VGA connection. Whilst this is still a very common connector, a recent computer is likely to have an HDMI output, which will offer better quality on-screen and carries sound as well.
Phono (-stage, -input,
All things to do with a turntable refer to all things phono, and any
phono-stage, -input, -amplifier is similarly describing such vinyl
deliciousness. Phono cartridges work at very low voltages and require
additional amplification before reaching the line-level parts of a
Phono Pre-Amp (also known as Phono Stage)
The signal from a turntable is much weaker than line level (see above) and therefore requires additional amplification. A phono pre-amp can either be built into your turntable or amplifier. If neither is so equipped, you’ll need to purchase a separate device. If you use an MC (Moving Coil) cartridge, do ensure that the phono pre-amp is compatible (MM, or Moving Magnet, is standard).
An individual dot of a digital image or a TV screen. The number of pixels an image or screen is made up of is known as its resolution, expressed as the number of pixels across by the number high (horizontal times vertical). So, for example, a 1080p image is 1920 pixels across by 1080 high. Generally, the higher resolution, the better quality an image is likely to be, but both your TV and your signal have to be compatible to benefit. For example, 1080p is a high resolution, but you won't enjoy that clarity watching standard definition TV, which has a resolution of just 720 x 576.
Pixel resolution – horizontal times vertical. Generally, the
greater the number of pixels, the more detailed the image.
Flat screen displays that use heated phosphors to create the pictures. Available in sizes from 42" upwards, plasmas are capable of showing both significantly better contrast and sharper motion than an LCD/LED set. They are fantastic for lovers of movies, sports and more. The caveat? Firstly, plasmas are only capable of showing off their stunning contrast in darker environments, so they're not for people with very bright rooms. They also use more power than LED sets, though for some this is a small price to pay for the picture quality.
A power amplifier is perhaps the simplest piece of hi-fi equipment. It's the one that makes stuff loud! They most commonly have two inputs and two outputs; one for the left channel and one for the right. The sound comes in from the preamp via an interconnect cable (either phono or XLR) and goes out via speaker cable. The advantage of breaking this part of an amplifier design out into a separate box is that the high current amplification circuitry can generate interference that has a negative effect on other signals in an integrated design.
The pre-amplifier is the bit that you interact with, choosing the source and setting the volume, as well as any bass and treble adjustments. Unlike a regular amplifier, it can't connect directly to speakers; you’ll need a power amp to boost the sound to the right level first. Well, actually, that's not entirely true as you can use a pair of active speakers, which have an amp built-in. You also get pre-amplifiers designed for home cinema use, though these are normally referred to as processors.
One of the last innovations in CRT technology before flat-screens took over was progressive scan. This "drew" the entire picture simultaneously, rather than the interlaced method of the odd lines and then the even lines shortly after, as had been the norm for the tech since its invention. This gave a very stable and clear picture. These days, all TVs are progressive scan, indeed the 'p' in 720p and 1080p stands for progressive. However, interlaced signals are still used, such as the 1080i (yup, ‘i’ for interlaced) resolution used for pretty much all HDTV broadcasts in the UK. Now these have to be "de-interlaced" by your TV's processing chip and how well it does it has an effect on the final picture quality though, to be honest, it's pretty subtle.
For true cinema-style impact at home, nothing beats a projector! Plus, in recent years the quality has taken a big jump up, whilst prices have come down. There are some practical drawbacks, though; for example you really need a dark room to get the absolute best performance, but we think it's worth the effort. If you're not convinced, every store has projectors set up in their demo room, ready to blow you away. For more information about specific projector types, see DLP, LCD projector and LCoS.
Pure Audio is one of the highest quality ways of enjoying High Definition music. What’s more, you may already have all the playback equipment required; without even knowing it! The format used is Blu-ray so a Blu-ray player connected via HDMI to an AV receiver will give you direct access to this great HD audio format. The vast majority of recordings also offer the option of surround sound. Finally, you can usually switch between stereo, 5.1 and 7.1 channels via the colour ‘fastext’ buttons on your Blu-ray remote.
PVR (Personal Video
Recorder)/DVR (Digital Video
A PVR is basically a dedicated TV-recording box. The Sky+ box is one example, but you can buy PVRs compatible to almost any TV system, including Freeview, Freesat and YouView. The main feature that distinguishes these from DVD/HDD recorders is that they record exact copies of the original broadcast, meaning recordings look exactly the same as live TV. They also tend to be easier to use with regards to features like pausing live TV. Ultimately, if you're not bothered about recording programmes to DVD, you'll probably be better off with a PVR.
RDS, standing for the Radio Data System, arrived in the UK in the early
90s, adding a basic data and text service to FM radio, normally the
station name. RDS also enables traffic reports to be automatically
received by those listening to an RDS-enabled radio in their car.
An amplifier that also comes with a radio tuner on board. It is very rare to see simple stereo receivers, although they are supposedly quite popular over the pond. More frequently, such a combination is found on a home cinema amplifier. In fact, it's generally safe to assume that when someone says "receiver" they mean an AV receiver (AVR) specifically.
Time taken for screen to respond in milliseconds. A small figure means that there is a quicker response time, giving images a cleaner, clearer appearance with fast motion sequences. Like contrast ratio, this specification is now quoted less often by manufacturers.
Like DVD-Audio, this is another next generation audio technology, which promised extremely high quality replay, allied to potential surround sound mixes. And like its one-time competitor it hasn’t really caught on. That’s not to say it doesn’t work. Results can be spectacular, if you can find the software. Hardware is not so much of a problem as a surprising number of Blu-ray players support the discs. SACD uses a very different technology from CD or DVD-Audio, implementing a one-bit delta-sigma modulation process known as Direct Stream Digital (DSD), with a very high sampling rate of 2.8224 MHz. This is 64 times the sampling rate used in making compact disc, hence the improved sound quality.
In nature sound is constantly changing. To create a digital representation of this sound we have to take a number of "snapshots" - or samples - which, when played back, sound like the original sound. On CDs this is 44,100 times a second, expressed as 44.1kHz. A higher sample rate gives an even more accurate recreation of the original sound, with high-end network music players and DACs regularly playing back material with sample rates of 192 KHz or more.
SCART (Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs – Radio and Television Receiver Manufacturers' Association)
SCART used to be the most common standard for connecting audio-visual equipment together. With its 21-pin adaptor, SCART was a nice simple solution for carrying audio and visual signals. Somewhat usurped by HDMI now, but TVs usually still come with one SCART socket.
Sensitivity is a measurement of how efficient a speaker is. It gives you an indication of how easy a particular model will be to drive compared to another. The figure is found by inputting a speaker with 1 watt of white noise and measuring the volume in decibels (dB) from 1 metre away. The higher the number, the louder the speaker with the same input power. Above 89dB and the loudspeakers will be a breeze to drive. If the figure is low – anything below 85dB – get yourself a monster amp as the speakers will need power aplenty to really sing.
A server is the name given to a unit that records, stores and replays your music or video. At its heart you’ll find a hard disc drive (HDD) that stores the information, controlled by special software to record and playback.
Very similar principle to your smartphone, Smart TVs come ready-equipped with internet capability. Once connected to your router (usually wirelessly) they will give you access to a plethora of different apps. Content varies from brand to brand, and model to model, but generally you get social media apps like Facebook, Twitter and YouTube, plus a full web browser and access to catch-up services such as BBC iPlayer. Some also include interactive features such as face recognition along with voice and motion control, but these are only available on certain models, so be sure to check the instructions before you start talking to your television – especially if the neighbours are watching.
One of the most recent and popular additions to the home-cinema market, a soundbar consists of two or more amplified speakers built into a long, bar-shaped chassis designed to fit snugly under your television. Connections vary from model to model, but their primary purpose is to boost the sound of your TV’s speakers – you can connect almost any AV or hi-fi component into a soundbar, even your mp3 player! More sophisticated models come with separate (and sometimes wireless) subwoofers for extra bass, Bluetooth connectivity, as well as simulated surround sound.
A soundbase works on a similar principle to a soundbar (see above) put is encased within a deeper cabinet that’s designed to fit beneath your TV.
This is the three dimensional audio picture a pair of speakers paint.
When correctly set up a system should create such a soundstage, where
sound doesn’t appear to emanate from the speakers themselves, but
around them, with musicians placed within this stage. A classic example
with current sound engineering is to have the lead vocalist positioned
centre stage, so his or her voice will appear to come from between the
An audio enhancement feature, TruBass enhances the perception of bass
frequencies to provide deep, rich bass response from any size speaker.
Sound that surrounds! Used primarily for gaming and watching movies, a typical surround sound setup requires an AV receiver and a 5.1 speaker set, meaning five speakers and one subwoofer. The speakers are placed in specific locations to create an ambient illusion of being immersed in the movie or game. A pair of speakers, one on either side of the TV or projector screen, takes care of music and the main breadth of sound effects. A centre speaker above or below the screen deals almost exclusively with dialogue, and another pair of speakers at the back of the room or behind the viewing position handles atmospheric sounds, or anything that goes on “behind” the main action. The subwoofer usually sits behind or to the side of the screen for best results. Depending on the size of your room, you may also add two more speakers at the front or sides to make 7.1 (seven speakers, one sub) 9.2 etc.
S-Video means separate video, which is a quality analogue video
connections. It carries the video data as two separate signals
(brightness and color). Many devices have both S-Video and component
video inputs (along with the composite video input). S-Video does not
carry audio on the same cable.
THX was originally founded as part of Lucasfilm to ensure that the soundtrack for Star Wars: Return of the Jedi would sound up to George Lucas' standards in cinemas. The company has since become its own separate entity, which tests home cinema kit against its exacting standards. There are two levels of THX-certification, Select2 - for small to medium rooms - and Ultra2 - for large rooms. Both of these also have 'Plus' variants, which adds extra processing to make sure you get a balanced sound at all volumes, not just full whack!
THX Ultra2 & Ultra2 Plus
THX Ultra2 is a 7.1-speaker extension of the original Ultra spec.
Ultra2 is designed to work well with multi-channel music and movie
presentations playing up to reference levels in rooms of 3,000 cubic
feet or larger. "Plus" adds volume control technology amongst other features.
THX Select2 & Select2 Plus
THX Select is a more affordable version of THX Certification. It is
designed to play at reference levels in rooms of approximately 2,000
cubic feet. "Plus" adds volume control technology amongst other features.
Basically a technical term for a sudden loud sound, usually one whose volume "cuts through" everything else, like a snare drum for example. These are a really good test of a system’s responsiveness; the transient sound should be louder without drowning out everything else.
Another sound technology, for audio and home cinema systems. For more
information look at the site of SRS Labs Inc. at: http://www.srslabs.com
The thing found at the top of most loudspeakers! The tweeter is a drive unit that handles all the higher frequencies that need to be reproduced. Often shaped like a dome, more fancy variations include ribbon designs.
Having two tuners means you can record two programmes at the same time or watch one and record the other. This feature is most commonly found on PVRs and HDD recorders, but some TVs have it to. Bear in mind that, with TVs, you usually need to buy a separate USB drive to make recordings.
UPnP / DLNA
Universal Plug ‘n’ Play or Digital Living Network Alliance (DNLA) is a method of sharing digitally stored information between compatible devices through a shared internet connection. For example, if you want to show your friends your latest holiday snaps, you can access them from your computer and display them on your smart TV in all their glory! UPnP determines the devices compatibility and their role in the transfer i.e. which device will be sending or receiving data. DLNA has its own restrictions to govern the type of information that will be sent, such as music or video files. With more DLNA-compatible devices becoming available every year, including Blu-ray players and smartphones, you can integrate your media files with your home cinema like never before!
When the picture you want to watch isn't the same resolution as your TV, it needs to be upscaled to fit; otherwise it would be a tiny image in the middle of the screen with swathes of black all around. The process of upscaling is effectively guessing new pixels to fill in the gaps. Some systems, such as those found in higher-end Blu-ray players, make more sophisticated guesses (or "interpolations" to use the techy term) than others, resulting in pictures that appear sharper from the same DVD. A lot of units advertise their "4K upscaling" technology. This is exactly the same process as what's described above, but for the new many-pixeled Ultra HD (4K) TVs. With such a set it's more important to make sure you have high quality upscaling, as a lot of what you watch will still be either standard definition or regular 1080p HD.
A measurement of power. In hi-fi parlance it tells you how powerful your amplifier is or the amount of power your speakers can handle. Remember power doesn’t always equate to quality, so a powerful amp isn’t necessarily the best. Sometimes manufacturers tweak the figures by quoting at lower impedance or at a high amount of THD (Total Harmonic Distortion, which should always be below 0.1% for accurate power ratings). We always aim to quote the most accurate "real world" power rating for amplifiers in the specifications on our website, so you can make fairer comparisons.
With wireless routers now included with nearly every broadband service, not to mention beaming through coffee houses throughout the land, wi-fi has reached near ubiquity. But what does wireless Internet and networking mean for your TV, hi-fi and home cinema? With more and more units offering connection to the web, built-in wi-fi means easy access to your existing internet connection. Besides the web, a network connection is needed for those fancy smartphone and tablet remote control apps. All in all, from TVs to AV receivers, built-in wi-fi is a very useful feature to have!
The driver in a loudspeaker that looks after the lower frequencies. In
most speakers – which are two-way designs – this is
actually a mid/bass driver.
YouView is a rival system to Freeview and Freesat and gives you the best of both worlds by offering free to view digital HDTV and a wide range of catch-up TV services. It makes catching up on TV particularly easy by offering the now much copied, ‘scroll back’ programme guide.
A balanced audio connector usually found in professional audio equipment, you might recognise it as a microphone lead. An XLR is also a great way of connecting your premium hi-fi setup together. XLR cables provide a superior connection, plus they include an extra pin, to eliminate "ground hum".