The Audyssey DSX Surround Sound Format

Audyssey DSX Logo. Logo provided by Audyssey

Dynamic Surround Expansion

In the evolution of Surround Sound, Yamaha's Presence and Dolby's ProLogic IIz were the first audio processing formats to introduce the concept of adding front height channels into a surround sound setup, with the goal providing a more immersive surround sound experience.

In addition, Audyssey, developers of several automatic speaker setups and room correction systems incorporated into many home theater receivers, also followed with its own twist that is designed to enhance the surround sound experience, Audyssey DSX (which stands for Dynamic Surround Expansion).

While Audyssey DSX, in a similar fashion to Yamaha Presence and Dolby ProLogic IIz, adds provisions for adding a front height channel. However, it has also added another twist by providing a surround sound processing option that allows installing either front height speakers or wide channel speakers. The wide channel speakers are placed in between the left and right surround speakers and the left and right front speakers. This option is designed to eliminate sound dips that can occur between the front and surround speakers than may occur, especially in a larger room.

Also, depending on the number of amplified channels that may be provided on specific home theater receivers, Audyssey also includes the option of adding both front height and wide channel speakers in the same room setup.

Just like Yamaha Presence and Dolby ProLogic IIz, the ability to use or experience DSX does not require studios to mix soundtracks specifically for the expanded sound field.

In other words, the DSX processor looks for cues already present in 5.1 or 7.1 channel soundtracks and directs them to added front height and/or wide channels, enabling a more enveloping "3D" sound listening environment.

Channel and Speaker Configurations

In order to experience the maximum benefit of Audyssey DSX, you need a 9.1 channel home theater receiver that is Audyssey DSX-enabled.

However, DSX is adaptable for use in 7.1 channel configurations (you have to choose between using front height or wide speakers).

In a full 9.1 channel DSX setup, the speakers are arranged as follows: Front Left, Front Left Height, Front Center, Front Right, Front Right Height, Wide Left, Wide Right, Surround Left and Surround Right. The Wide Left and Wide Right speakers are placed on sides between the front and surround speakers. The .1 channel, of course, is reserved for the Subwoofer(s).

However, if you are limited to a 7.1 channel setup, you have two options: You can eliminate either the front height or wide speakers. Audyssey recommends that if you have to make this choice, adding wide speakers should be a higher priority over adding the front height speakers.

This type of speaker layout allows for the expansion of the surround sound field that fills in the gaps between the surround and front speakers, as well as adding a larger front soundstage with the addition of height channels placed above the front left and right front speakers. The sound from the height speakers also projects toward the listening position, giving the sensation of selected sounds coming from overhead.

Audyssey DSX and DSX 2

Home Theater receivers that are equipped with Audyssey DSX have the ability to upmix 5.1 or 7.1 channel content, while DSX 2 adds the ability to upmix 2.0, 5.1, or 7.1 channel content into the intended expanded surround sound environment.

More Info

Although there are some home theater receivers that come equipped with the Audyssey DSX or DSX2 surround sound processing formats, with the introduction of the Dolby Atmos, DTS:X, and Auro3D Audio immersive surround sound formats, as of 2015, home theater receiver makers have moved away from including the Audyssey DSX/DSX2 options.

However, if you have a home theater receiver, or happen to buy one, that has either DSX or DSX2 as an option, it can still be used, as it does not require specific encoding on the source end, and can definitely expand your surround sound listening experience over standard 5.1 or 7.1.