Posted on Sat, 02 Dec, 2023
Posted by Geoffrey Whittaker

What is surround sound?

In this guide to home cinema systems, we look at a basic system as well as a more advanced Dolby Atmos system. Surround sound has been around much longer than is appreciated. It began in Cinemas and was pioneered by Walt Disney in 1940. Fantasia had a multi-channel soundtrack with three audio channels and a control track. two protectors were used, one for the film and the other for the stereo soundtrack and control track. Three speakers were provided at the front. notably, these were left, right, and centre. additionally, there were three speakers at the back of the auditorium. These provided a surround effect. Fantasound as it was known was developed by RCA and Disney at the astronomical cost of $4.2 million in today’s money.

What is the difference between 5.1 and 7.2.4?

Speaker packages

Today there are many different encoding methods and ways of setting up speakers for home cinema systems. The most common is 5.1. This comprises a front left and right set of speakers along with a centre speaker for dialogue. There are also two surround speakers as well as a subwoofer. A good example of a speaker package is the Q Acoustics 3010i 5.1 Cinema Speaker Package. This is an award winning set with four Q 3010i bookshelf speakers and a Q 3060 Subwoofer. There is also a Q 3090i Centre speaker. This compact set is good for small to medium sized rooms and delivers punchy bass for movies and music. You will also need a suitable AV receiver that can decode the surround sound signal and drive multiple speakers.

AV receivers

A good example of a 5.1  AV receiver is the Yamaha RX-V4A . This can actually create a 5.2 system with two subwoofers.

It is instructive to look at the back connections of one of the simpler AV receivers, such as the Yamaha RX-V4A Black 5.2 Channel AV Receiver. in this way you can understand the basic connectivity.

Starting with the video inputs, there are usually several HDMI inputs for connecting video sources such as Blu-ray players and games consoles. There will also be an output for connecting a TV or projector. Higher cost units will have more inputs and outputs. Most AV receivers will be ARC capable meaning that you can control the volume with your TVs remote control. As the  Yamaha RX-V4A is an entry level unit there is a helpful speaker connection diagram on the back.
Next, there is usually a  range of analogue and digital inputs for connecting audio components. Some units will also have a phono preamp stage. Finally this unit also has line level outputs for two subwoofers.  However, the ultimate home cinema systems use Dolby Atmos.

What is Dolby Atmos?

Modern cinemas use Dolby Atmos sound systems. Consequently, Dolby Atmos has found its way into the home. AV receivers such as the Marantz Cinema 40 AV Receiver can be used to create a Dolby Atmos 9.4 system. As can be seen from the back they are far more complex than 5.1 systems receivers. The Marantz Cinema 40 AV Receiver has a higher power output per channel , At 125 watts, and can drive eleven speakers.

About Dolby Atmos

Dolby Atmos was first used in cinemas in 2012 and there are now around 10,000 Dolby Atmos equipped cinemas around the world. Additionally, from 2016 some TV series and music tracks have been released in the Dolby Atmos format. Each movie soundtrack can have up to 128 tracks or sound objects. These also have metadata that tells the processor the location in 3D space and volume level, amongst other data for each sound. Dolby surround speaker systems can have various configurations. Notably the numbering  system is slightly different. For example a 7.1.4 Dolby Atmos system has seven front and surround channels, one subwoofer and four ceiling speakers. Home systems use sixteen sound object clusters that can be located anywhere in 3D space for an immersive movie experience.

Surround sound encoding methods

Knowing a little about the history of home cinema encoding methods can make it easier to understand the different formats now available. Attempts at domestic home cinema were made almost as soon as stereo VHS tapes became available in the 1980s. This system was known as Dolby surround. Dolby surround provided a rudimentary surround sound system. The system had poor bandwidth and limited separation. Dolby Digital was the next surround method in use. DVDs used Dolby Digital to create a five channel system. There was also a low frequency effects channel.
DTS is a rival system that resembles the Dolby offerings. DTS stands for Digital Theatre Systems and uses a higher bit rate than Dolby. There are also different versions such as DTS HD that supports 7.1 systems. the main difference is the bit rates and compression. For example Dolby supports 640 kbits/s (kilobits per second) on Blu-ray discs while DTS supports supports higher bit-rates of up to 1.5Mb/s (megabits per second). Both systems are good and most modern AV receivers can decode both systems.

Separate processors and amplifiers

Finally there is another layer to the home cinema story. That is the separation of functionally, with more advanced systems. For example Marantz produce a range of AV processors and amplifiers that can be used to make very complex systems. One such AV processor is the Marantz AV7706 AV Processor. this is the flagship model in the range.

This processor is intended as the front end of the ultimate home cinema system. It can be used to create 11.2 systems and is meant to be used with a separate amplifier such as the Marantz AMP10.


The AMP10 is a sixteen channel power amplifier intended for home cinema systems. The point of separating the units is twofold. Firstly, it prevents mutual interference. Secondly, it gives greater versatility. The units could even be in different rooms and they are both provided with balanced inputs and outputs. This allows for long cable runs without any noise being introduced.


Overall you can make up a home cinema system depending on the size of the available room and your budget. Moreover most disc formats and many streamed movies have surround sound encoded with them.

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