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Sound bars glossary

By Jack Turner

Before you choose a sound bar, it helps to understand the key terms. Our jargon-busting glossary explains the different terms and how they will affect your choice.

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A sound bar is a bar-shaped enclosure of speakers that, when plugged into the TV, bypasses the internal TV speakers. It's a neat and tidy option that is designed to sit on the same stand as the television fitting snugly below the screen, although some can also be fixed to a wall using mounting brackets. Sound bars are a compact alternative to home cinema systems which come with several speakers to be placed around a room. While sound bars are generally simpler to setup, many of the same technical terms are used when referring to their specifications.


Analogue audio inputs

The old method of connecting bits of audio equipment is with analogue inputs (red and white phono sockets and connectors). If you connect this way, some TVs allow you to use the TV's remote to control the volume of the sound bar. However, many new televisions no longer feature analogue inputs.



Cables from the cheaper end of the market will normally do the trick for sound bar set-ups. However, cheap cables used over 'long runs' may deteriorate sound. It's not as relevant for sound bars but, if you have a discerning ear or an expensive audio system, you will probably notice. We’d recommend you spend a minimum of £2 per metre and up to £10 per metre if you need to have decent terminals fitted.

Like HDMI cables, audio cables can go up to ridiculous prices with Oxygen-free cable, solid silver and even directional cable. These can generally be disregarded.


All the sound bars we’ve tested would work with any brand of TV. They will work with any size of TV too, but for aesthetic reasons they are best suited to particular screen size ranges (usually from 40 inches to 50 inches). A sound bar that's too long or short for your TV display might look a bit odd.

The good news is that, in most cases, there’s no need to attach the sound bar to the television. Sound bars are designed to sit on the same stand as the TV and fit underneath the screen.


Digital optical (Toslink)

On some TV brands, analogue outputs have been phased out and superseded by digital audio outputs, though many more feature both types. The most common is known as Toslink, or digital optical.

However, Toslink doesn't quite have the convenient functionality of some HDMI or even analogue inputs. Toslink carries surround sound as well as stereo, and is commonly used for connecting to home cinema systems.



A feature found on newer TVs, ARC stands for audio return channel. It's easy to spot as the socket on your TV will normally be labelled ARC (but check the user guide if in doubt or it doesn't work). A sound bar with an HDMI ARC socket has the advantage of having a single connection that can deliver digital audio and provide CEC remote control.


Most HDMI sockets support some sort of consumer electronics control (CEC) feature. This allows you to control other bits of CEC-enabled equipment, such as the volume and power of your TV, via just one remote control.

Different brands give CEC different names such as LG Simplink, Samsung Anynet+, Sony Bravia Theatre Sync, and Toshiba Regza link. Many manufacturers imply that their TVs will only link with AV equipment from the same brand, but basic CEC functionality usually works between brands - just make sure HDMI CEC is enabled.

Headphone port

Most sound bars have a 3.5mm mini-jack input, commonly referred to as a headphone port. This is useful for playing music from a portable audio device such as an MP3 player, but it can also be used for the TV if it's not possible to connect it via a digital connection. However, if both your TV and sound bar have a digital connection, such as HDMI or Toslink, we recommend using this instead.


Power usage

Sound bars don't tend to use too much extra power - usually around 10 watts or less, no more than a typical table-top radio. Many sound bars switch to standby if no signal is detected from the TV, but they don't tend to have an actual 'off' switch. We provide power information for each model in our reviews.



Most sound bars have an additional speaker called a 'subwoofer', which is designed to deliver extra bass. It is often built into the sound bar, but some have an external subwoofer speaker which is about the same size as a bookshelf speaker. Sound is either passed to an external subwoofer over a wired (audio cable) or wireless (Bluetooth) connection from the sound bar.

This will normally be a big plus for film fans, but our experts feel the extra bass is probably excessive for serious music listening.



Audio power is measured in watts, which describes the energy output of the receiver or amplifier that powers a loudspeaker (such as a sound bar). The power output of all of the sound bar system's speakers (including the subwoofer) is normally stated as the total 'watts RMS'. The figure given for a sound bar's audio output shouldn't be confused with that stated for its power use which, confusingly, is also given in watts.

Watts aren’t actually a measure of volume - which is measured in decibels - but rather power. A higher audio wattage can result in a wider, richer range of sound, but this type of power doesn't always equate to quality, and sound quality is what counts.

So, a powerful sound bar isn't necessarily the best. Our listening tests assess the sound quality of speech, music, TV, and film across different tracks, so you can choose a sound bar that offers the best chance of improving your TV's sound. We've also provided the recommended audio settings from our listening tests in the 'full specification' tab of each sound bar review.


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