Discussing the ease of integration of Dolby encoding within Fairlight

Whilst surround audio production for HD TV requires a new type of audio-production environment with full multi-channel surround audio capabilities, facilities also need to consider the integration of multi-channel production finishing tools, in particular the installation of encoders and decoders, within their surround-capable mix consoles and multi-channel audio monitoring systems.

Adding these devices greatly increases the overall complexity of newly designed audio rooms but making the transition successfully doesn’t have to be all about buying lots of new gear and implementing technical changes.

Dolby Digital and/or Dolby E

One of the biggest challenges today involves the process of creating Dolby multi-channel surround-audio content. Facilities need to be able to monitor the encode process in real time so that the mix maintains compatibility when the signal is decoded. In addition the mixer must decode the surround signal prior to routing the signals to amplifiers and speakers. Since, potentially, the signal is delivered to the consumer in a wide range of listening environments — from mono to full 5.1 surround — the operator should be able to monitor the mix in these different formats to assure signal compatibility. 

We have heard a lot of talk these days about “Mixing in the Box”. Well … we here at Fairlight, like to use the term “Mixing without Compromise”. One of the main reasons that we use this expression is that DREAM products, with their powerful mixing and automation features, also include powerful and comprehensive “Monitoring in the Box”. No compromises here!

Fairlight’s highly flexible monitoring system is completely configurable with programmable fold-down and fold-up modes allowing instantaneous switching to up to nine different speaker sets and  16 external source feeds, each of which can be configured for any desired buss format – Mono up to 7.1 !  Fairlight systems also provide control of up to nine sets of monitor speakers or headphone feeds for the Studio. Studio monitors can be in mono or stereo formats.

16 Programmable Control Room Monitor Sets and eight Studio Monitor Sets provide storage and instant recall of any complete monitoring configuration. These Monitor sets can store setups as simple as source selection, or as complex as a complete monitoring configuration including: fixed level, speaker mutes, speaker set, monitor format and sources.

The embedded Monitor matrix can manipulate any physical I/Os in either analogue, AES, AES SRC, and MADI formats and a sophisticated internal patching system allows totally free routing of inputs, outputs, and Busses between external and internal destinations.

In addition … an Alternate Format switch lets you instantly hear your work in any pre-determined fold-down/up desired. You could listen to a 5.1 mix in 7.1 channels, all the way down to mono. Fold-down and Fold-up laws can be tweaked and saved in a user-defined stored text file.

Inserts in Monitoring

Inserts in monitoring can very easily be chosen by using the Source Setup Menu, which allows any physical inputs to be monitored. This allows, for instance, both the Lt, Rt outputs of a Dolby encoder and the individual LCRS outputs of a Dolby decoder to be monitored directly as external monitor source inputs … and all of this in a pure digital domain if desired!

All of this adds up …

These are all important considerations for a multi-format surround based audio facility, as once again, this power and flexibility is essential when multi-channel audio monitoring is involved.

Unlike the Digidesign ICON systems it is not necessary to add an expensive third party monitoring system to provide the functionality that is missing. Even though these systems offer some basic monitoring facilities they are analogue only and cannot handle digital sources unless you buy more converters.

Same thing for DAW controllers such as the Euphonix System 5-MC, and that other Smart Australian controller, remember that these are ONLY controllers and not a console.  Monitoring / foldback / talkback system? You are only relying on your DAW for this, and I still don't think any DAW does this as well as a proper console.

In addition, and to further to exacerbate the cost, attaching external third party monitoring systems will require a great deal of additional I/O. Despite all this extra cost you are still only left with a compromised “fix” sourced from two separate manufacturers and not a true integrated system. For us … “Monitoring in the Box” is an integral part of “Mixing without Compromise”.

With Fairlight, Xynergi MPC, Constellation, and Anthem we offer a very tight integration for a Dolby based encoder/decoder system, with single-key configuration from the control surface for a variety of operational modes, including external machine setups, bussing structure and formats, and monitor formats and modes.

Example:

Click on the following PDF link for nice example of DREAM/DOLBY integration … inspired from “right around the corner” here in Sydney.

Click here for PDF Diagram

Hopefully some of you can refer to this document when designing your studio in association with similar Dolby requirements. Integration of connections of the DP571Dolby E Encoder, DP572 Dolby E Decoder, DP570 Multichannel Audio Tool, DP563 Dolby Surround and Pro Logic II Encoder, Sony - DVWM2000MP Digital Betacam, Dolby Cat.549. GPIO Remote Controller, Dolby Remote 570 Windows Software.

1) DREAM monitor Analogue outputs 1-8 ( Mon - L,R,C,Sub,LS,RS, TV-L & TV-R )

2) Main Buss ( up to 7.1 ) out to Digital Audio In. DP570 – QDC digital outputs ( 41-48 )

3) DP570 Emulator Outs. Digital audio outputs for monitoring the effects of metadata and
    downmixing on the audio program. These outputs are affected by metadata changes and  
    are used to send a signal to the back to the monitoring system. QDC digital inputs 41-48.
    Coming in directly as an external source for monitoring.

4) Main Buss out – ( digital outputs from QDC 1-8, Multiple Mode ) to DP571 Dolby E  

    Encoder.

5) Main Output (Dolby E stream) from DP571 Dolby E Encoder going to DigiBeta AES inputs

    3 & 4.

6) DigiBeta AES outputs 3 & 4 to Main In - DP572 Dolby E Decoder.

7) DP572 Dolby E Decoder - Dolby E ( Decoded ) Channels 1 – 8 / AES Out to QDC Digital 

     inputs, Coming in directly as an external source for monitoring.

8) Processing delays – Another challenge.

The Dolby E and Dolby Digital encoders and decoders all have processing delay through them. The Dolby E encoder and decoder each have a one-frame delay.

Now here’s something clever … Showtime lays down an additional PCM stereo mix of their program audio onto the Digibeta’s Digital inputs 1 & 2. What about the delay? Well, 1st off they use a QDC editor Macro to offset all the audio by 2 frames.

They use an additional stereo mixbuss (how about buss reduction) and output this buss using QDC digital outputs 9 & 10. This mix runs to the DP572 Dolby E Decoder’s delay in-out path where they pick up one frame. Then, this mix runs through the DP571 Dolby E Encoder’s delay in-out path where they pick up the additional frame. Then, it goes straight to Digibeta digital inputs 1 & 2.

Result - A one frame difference between the Dolby E on Digibeta tracks 3 & 4 and the standard PCM mix on 1 & 2. Now … decode the Dolby E on 3 & 4 and both mixes are now in sync!

No additional delays are required.

9) This mix also comes back into the QDC on Digital inputs 9 & 10 (Digibeta AES outputs 1 &

     2) as an external source for direct monitoring.

10) If required, an additional or “parallel 5.1 mix” (another sub/reduction buss for more  
      control) using QDC digital outputs 33-38 can be sent to the DP563 Dolby Surround and   
      Pro Logic II Encoder. Lt/Rt output from the encoder can be sent back to the QDC, digital
      inputs 11 & 12. Patched either to a Live/Ret feed. These can then be assigned to another
      Sub-Buss and once again, using “Multiple Mode”, patched out using QDC digital outputs
      11 & 12 to the DP570 for monitoring. At the same time … patched out of QDC digital
      outputs 7 & 8 to be laid back to corresponding input channels 7 & 8 on the DP571
      Dolby E Encoder, therefore embedding the Lt/Rt mix into the Dolby E stream if desired.