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Dolby® Digital Plus™ extends the capabilities of Dolby Digital, optimizing sound quality and efficiency for a richer, cinematic audio experience.

Delivers scalable sound, optimizing quality and efficiency for available bandwidth

Supports a wide range of existing and emerging home theater, broadcast, streamed content, and mobile applications

Provides up to 7.1 channels of cinematic surround sound for a more involving experience and dramatic special effects

Includes compatibility with millions of existing playback systems

Dolby Digital Plus is a versatile digital audio coding technology that extends the capabilities of Dolby Digital. Dolby Digital Plus delivers up to 7.1 channels of cinematic surround sound, with scalable sound delivery and a wide range of bit rates ensuring optimized sound quality and efficiency for the available bandwidth. These advances are just a few reasons why Dolby Digital Plus delivers a more enveloping audio experience for existing and emerging applications, including new digital broadcast TV formats, Internet-delivered audio, and high-definition video discs.

Dolby Digital Plus for Over-the-Top (OTT) Streaming

A new era in home entertainment has arrived. Consumers increasingly stream online content to their living room systems—and they expect the same high-quality surround sound they get from HD broadcast and packaged media. Dolby Digital Plus offers the best way to deliver this solution. It’s fully compatible with existing A/V entertainment systems and has the flexibility to adapt to any bandwidth delivery requirements.

Learn about the advantages of Dolby Digital Plus for streamed entertainment. (PDF)

Dolby Digital Plus for Home Theater

Dolby Digital Plus takes the home theater surround sound experience to the next level by enabling Blu-ray Disc™ and other digital formats to deliver more channels, less compression, and higher data rates.

Dolby Digital Plus also supports secondary audio applications for interactive BonusView content on Blu-ray Disc.

Why Dolby

With more channels, less compression, and higher bit rates, Dolby Digital Plus helps equipment manufacturers and content producers differentiate their products by delivering a sound experience that some reviewers have described as being “virtually transparent” to the original source.

Delivers up to 7.1 channels of surround sound from Blu-ray Disc players

Enables up to 13.1 channels of dynamic sound to support new and emerging content delivery formats

Supports interactive Blu-ray Disc features: BonusView, an embedded picture-in-picture option that mixes multichannel secondary audio and video content, and BD-Live, which displays content streamed from the Internet

Allows single-cable connection and full application of the A/V receiver’s digital signal processor (DSP) postprocessing and bass management via HDMI™ 1.3 data transport

Includes complete metadata support and backward compatibility with existing home theaters

Channels: 1.0 to 7.1, discrete

Data rate: 32 kbps–6 Mbps, scalable; typical range on HD optical discs is 768 kbps–1.5 Mbps

Supports Dolby metadata: Yes

Connections: S/PDIF, HDMI, IEEE 1394

Mixing/streaming capabilities: Yes

Backward Compatibility: Yes; S/PDIF to legacy A/V receivers (640 kbps data rate)

Connector Signal Types

Line output: Two-, six-, and eight-channel analog

S/PDIF: Two-channel PCM and Dolby Digital

HDMI 1.1/HDMI 1.2: Two-, six-, and eight-channel PCM and Dolby Digital

HDMI 1.3: Two-, six-, and eight-channel PCM, Dolby Digital, Dolby Digital Plus, and Dolby TrueHD bitstreams

Dolby Metadata Parameters

Professional metadata parameters are only carried in the Dolby® E bitstream and are used to configure a downstream decoder. Consumer parameters are carried in the Dolby E, Dolby Digital Plus, and Dolby Digital bitstreams, and are used by the consumer’s decoder.

Extended bitstream information parameters are in italics.

Metadata Parameter
Program configuration
Program description text
Dialogue level  
Channel mode  
LFE channel  
Bitstream mode  
Line mode compression  
RF mode compression  
RF overmodulation protection  
Center downmix level  
Surround downmix level  
Dolby Surround mode  
Audio production information  
Mix level  
Room type  
Copyright bit  
Original bitstream  
Preferred stereo downmix  
Lt/Rt Center downmix level  
Lt/Rt surround downmix level  
Lo/Ro Center downmix level
Lo/Ro surround downmix level  
Dolby Surround EX mode  
A/D converter type  
DC filter
Lowpass filter
LFE lowpass filter
Surround 3 dB attenuation
Surround phase shift

Special Parameters

There are other professional parameters included in the Dolby E bitstream that are not under direct user control, such as timecode and pitch shift.

Dolby Digital Plus

Dolby Digital Plus is a highly sophisticated and versatile audio codec based on Dolby Digital and designed specifically to adapt to the changing demands of future audio, video delivery, and audio storage systems while simultaneously retaining backward compatibility with the existing Dolby Digital 5.1-channel home theater systems in use today.

Choose from the drop-down menus below to get Dolby professional reference material.