If you’ve heard of surround sound before, you may be thinking of speakers positioned on all sides — front, back, left, and right. Such a setup does offer an immersive listening experience, but fails to account for another important dimension: height. In this guide, we’ll introduce you to height channels, which add verticality to the sound experience and thus offer a home theatre experience that resembles a real-life environment.

Understanding speaker channels

A surround sound system works by surrounding the listener with various different points of audio. These points are referred to as speaker channels. The number of speaker channels helps to determine how ‘immersive’ a sound system feels to the listener. Generally speaking, the more speaker channels, the more immersive the system.

Where the speakers are placed matters, too, though this is standardised in the most common surround sound configurations. A typical 5.1 surround sound system allows for five ear-level speaker channels and one subwoofer. These are placed in the following configuration:

• Three front channels (left, centre, and right)
• Two rear channels (left and right)
• One subwoofer

Another common configuration is the 7.1 setup, which adds two additional ear-level channels to fill any potential gaps in the sound experience.

It’s worth noting that adding more channels doesn’t necessarily require adding more speakers to your configuration. Some speakers and soundbars can deliver multiple channels at once. A Sonos soundbar covers the three front channels (left, right, and centre) all by itself.

A truly immersive sound experience depends on more than just ear-level channels, though. You can also add additional channels above ear level. These so-called height channels can bring an entirely new dimension to a surround sound setup.

What are height channels?

Put simply, a height channel is a point of audio positioned above the listener. This audio may come directly from an in-ceiling speaker (as is the case in many architectural setups), though height channels don’t necessarily require speakers positioned overhead.

Advancements in spatial audio design have led to new possibilities for adding height channels to a surround sound system. Object-based sound technology, such as Dolby Atmos, assigns different sounds to specific locations in a room. Speaker drivers positioned at the ear level can then fire certain sounds upwards, so that they bounce off the ceiling and hit the listener’s ear from above. The result is a truly three-dimensional soundscape, with sounds projected from all sides as well as from various different heights.

To account for this extra dimension of height, many speaker configurations now include a third number. For example, a 7.1.4 configuration includes the following:

• Seven ear-level speaker channels
• One subwoofer
• Four channels above the ear level

How do you get height channels at home?

If you think a 7.1.4 setup requires investing in an abundance of speakers, we have good news. You can achieve this exact configuration with as little as three speakers and a subwoofer.

To do this, though, you’ll have to choose a combination of a soundbar and speakers that supports the spatial audio capabilities of Dolby Atmos. Of course, you can also add in-ceiling speakers if you prefer a more architectural setup. Let’s take a closer look at these options.

Choosing the right speakers or soundbar

Installing speakers in your ceiling is the most obvious way to add height channels to your home theatre setup. It may make sense if you favour a custom, discreet solution that blends with your home’s design. Just note that this option may require a professional installer, and it’s not as flexible if you want to change the positioning of your sound system later down the line.

For most people, using Dolby Atmos-enabled speakers is a much easier path toward truly immersive sound. For example, you can achieve a 7.1.4 home theatre system with the following Sonos configurations:

• 1x Beam (Gen 2) + 2x Era 300 + 1x Sub
• 1x Beam (Gen 2) + 2x Era 100 + 1x Sub or Sub Mini

For a next-level immersive sound that rivals — if not beats — watching in the theatre, Arc Ultra renders a 9.1.4 surround sound experience from the soundbar alone. Pair it with two Era 300 speakers and Sub 4 for a listening experience you’ll have to hear to believe.

Several of these configurations are sold in immersive speaker sets, so you don’t need to buy them separately.

Streaming Dolby Atmos-compatible content

If you do opt for a Dolby-Atmos compatible setup, you’ll need to keep an eye out for content that’s specifically mixed in the Dolby Atmos format. Otherwise, your system will still sound good but may lack some distinction between height and ear-level channels.

Film and TV streaming services continue to expand their Dolby Atmos-supported libraries, and you should find a growing library of options on Netflix, Disney+, Apple TV, and Amazon Prime Video. Some music streaming services, like Apple Music and Amazon Music, also stream a selection of songs in spatial audio.

Experience height channels with Sonos

With the development of spatial audio technologies like Dolby Atmos, we’ve arrived at a new era of surround sound — an era where we’re opening new dimensions in the home audio experience. Height channels are the key development in this era, and you don’t need overhead speakers to add them to your home setup. If you’re interested in bringing a new dimension to your sound experience, get in touch with a Sonos expert by phone or chat.