The DTS Neural Surround™ DownMix provides a process for taking a 5.1 mix and creating a stereo mix. This is called a LwRw watermarked signal and is backwards-compatible with Dolby® ProLogic® II. The stereo mix can be monitored, mixed, stored, edited and played back using a stereo audio infrastructure.
DTS Neural Surround™ DownMix enables the transport of 5.1 surround sound through any stereo infrastructure. The process is based on the principle that both natural stereo and 5.1 content are two-dimensional; both contain width and depth spatial attributes. The DownMix can represent six channels of discrete audio sources in a stereo downmix by transforming the source positions into pure intensity and coherence.
| NEO 1RU Frame | 6800+ 2RU Frame |
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NEO 3RU Frame | Selenio 3RU Frame |
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| X85
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By transforming signal sources, intensity, time, coherence, polarity and phase into pure intensity and coherence before the six channels are combined, the DownMix amelio-rates problems suffered in traditional matrix encode systems (comb filtering, spatial distortion, etc). This proprietary DTS Neural Surround™ process, or watermark, guarantees that surround information is faithfully reproduced when later rendered by the UpMix and is backwards-compatible with Dolby® ProLogic II®. The stereo mix can be monitored, mixed, stored, edited and played back using a stereo audio infrastructure. In brief, the DownMix produces a stereo DownMix that accurately represents the original content, whether monitored in mono, stereo, matrix or Neural 5.1 Surround Sound.
There is a plug-in option available for adding the DownMix to the NEO® XHD-3903. The AES option for the XHD-3903 is required. Click here for more information on the XHD-3903.
The 6800+ platform includes the all-in-one APM6803+ Multichannel Audio Processing Station for AES and embedded audio processing. A range of single function modules is also available with the APM6801+ series.
There is a plug-in option available for adding the DownMix to the X85™ processors.
The Selenio™ Media Convergence Platform supports DTS Neural Surround™ DownMix as well.
Versions are available (see ordering information) for applications where DownMix and Loudness Control are required.
Commonly used in: production studios, audio monitoring, DTV facilities.
For more information, see the Neural Audio Website.
Block Diagram

DownMix with Loudness Control

5.1 Loudness Control with DownMix

Specifications and designs are subject to change without notice.
| Sample Rate | 32 to 48 kHz (AES/EBU, wordclock-slave) |
| Number of Available Channels | Depending on configuration, up to 4 AES3 input (stereo) and 4 AES3 output (stereo) |
DTS Neural Surround™ DownMix in 6800+ | |
APM6801DM+D | DTS Neural Surround™ DownMix DTV 5.1 transport solution on the APM6801+D |
APM6801LC+DM+D | DTS Neural Loudness Control for 5.1 program audio with DTS Neural Surround™ DownMix output on the APM6801+D |
| APM6801DM+LC+D | DTS Neural Surround™ DownMix DTV 5.1 transport solution with DTS Neural Loudness Control on the APM6801+D |
| DTS Neural Surround™ DownMix for NEO XHD-3903 | |
| XHD39OPT-DM | DTS Neural Surround™ DownMix DTV 5.1 transport solution, plug-in for NEO XHD-3903 (AES input/output version required, for field upgrade order XHD3903-UG-AESC) |
| XHD39OPT-LC+DM | DTS Neural Loudness Control for 5.1 program audio with DTS Neural Surround™ DownMix output, plug-in for NEO XHD-3903 (AES input/output version required, for field upgrade order XHD3903-UG-AESC) |
| XHD39OPT-DM-LC | DTS Neural Surround™ DownMix DTV 5.1 transport solution with DTS Neural Loudness Control, plug-in for NEO XHD-3903 (AES input/output version required, for field upgrade order XHD3903-UG-AESC) |
| DTS Neural Surround™ DownMix for X85/X75 | |
| X75OPT-DM | DTS Neural Surround™ DownMix DTV 5.1 transport solution, plug-in for X75 and X85 |
| X75OPT-LC+DM | DTS Neural Loudness Control for 5.1 program audio with DTS Neural Surround™ Downmix output, plug-in for X75 and X85 |
| X75OPT-DM-LC | DTS Neural Surround™ DownMix DTV 5.1 transport solution with DTS Neural Loudness Control, plug-in for X75 and X85 |