New Loudness Tools for System 6000 MKII

Dinsdag 03 juli 2012, 13:36 • 4383 keer gelezen

The Live Aid license allows you to easily comply with new loudness broadcast standards, even under live and OB conditions. It includes two pristine loudness processing algorithms plus a host of new presets.

Developed for broadcasters covering no compromise live events such as the London Olympics, one System 6000 MKII is now all it takes to upgrade an entire studio or OB truck with low latency, high resolution loudness processing for multiple platforms; at the same time metering adhering to American, European or Japanese standards on all outputs.

New Loudness Tools for System 6000 MKII

Live Aid includes two powerful algorithms, ALC6 and DMix, as well as a host of presets targeted to various loudness and true-peak requirements around the world.

ALC6 - Hit Your Target
ALC6 offers BS.1770 compliant Loudness Correction and True-peak limiting for mono, stereo and 5.1 programs. This low latency, 48 bit resolution processor may be used as a loudness safety-belt for easily hitting a -23 or -24 target directly from a live studio or an OB truck. Unlike a compression or limiting type of processor, ALC6 only performs adjustments when needed. Rest of the time, audio is passed untouched.

Keep CALM. Keep R128. Keep TR-B32
For live processing, select the "Not Normalized" profile, and decide whether ALC6 is allowed to add positive gain or not. The adaptive Stridency Reduction parameter brings overly loud content under tight control while leaving normal content untouched, and True-peak limiting on the 5.1 outputs sets a precisely defined upper limit to instantaneous level.

Live Downmix Compliance
Measuring the loudness of a 5.1 program can give significantly different results from measuring a stereo or a mono downmix of the same program. These differences are systematic because measuring loudness according to BS.1770 is insensitive to inter-channel phase differences, while a downmix is not. Tight tolerances on program loudness therefore presents a dilemma when it comes to mono or stereo listeners, generally the vast majority of a station's audience. 

ALC6 introduces a new way of dealing with this issue: A 5.1 program may be adjusted based on what it measures in 5.1, or on what it measures using a specific set of downmix coefficients. 

ALC6 also helps getting a higher audio quality and more headroom out of AC3 data reduction. The downmix part of the decoder is prone to overload, especially when AC3 DRC is set to Off. On the other hand, enabling DRC inserts a crude processor which nobody can get rid of again. Use the new "AC3 Codec" setting with ALC6's true-peak limiter to prevent downmix clipping while preserving headroom, thereby making it safe to switch off DRC and make AC3 more transparent.

DMix - Mobile Matters
TC's acclaimed Trickle-down processing is now available for System 6000 MKII. DMix is perfect for converting a 5.1 program to a great sounding mobile platform stereo version in a one-step process; at an impeccable audio quality, and at almost zero latency (0.8 ms).

DMix packs on-the-fly Downmix, Loudness Range conversion, EQ, MS Processing, 5-band Processing and True-peak Limiting into one single, powerful Engine. Consequently, the user may concentrate on a 5.1 mix while DMix takes care of stereo simulcast for mobile or web platforms.

Presets
All Live Aid presets are found in the new F13 Loudness preset bank. 

Three ALC6 and three DMix preset folders targeted to ATSC A/85, EBU R128, ITU-R BS.1770-2 and TR-B32 requirements are included with the license. Note how we're continuing the trend from DB4 and DB8 of having separate folders for dedicated ATSC, EBU and Japan presets. 

DMix presets include iX types with image enhancement for listening in headphones or listening to desktop speakers.