Product Information

Sentinel Summary Brochure

Describes the features and capabilities of the Sentinel Surround Sound Audio Monitor with a focus on Broadcast Loudness and QoE Monitoring and CALM Act Loudness Compliance. Includes product specifications.

>PDF format, 2 pages, revised 09-Apr-2012

Sentinel Introduction

Slides and audio commentary introducing the Sentinel Surround Sound Audio Monitor. Describes the motivation behind the product, its monitoring functions, and its principal areas of application in the broadcast environment.

>PDF format, 15 pages, 289 Kb, revised 24-Jul-2013

Sentinel VisiLog Reports Brochure

Introduction to the capabilities and features of Sentinel VisiLog Reports, a reporting function that merges audio measurement data with your as-run schedule. Describes how you can use particular types of reports to monitor and analyze your broadcast audio, and how they can help you avoid CALM Act compliance problems.

>PDF format, 4 pages, 2.4 Mb, revised 23-May-2013

Sentinel User Manual

Guide to installing and using the Sentinel Surround Sound Audio Monitor. Printed copies are also available from Qualis Audio.

>PDF format, 112 pages, 2.5 Mb, revised 01-Jul-2013

Sentinel Release Notes, Version 1.34a

Describes enhancements, corrections and known issues for version 1.34a of the Sentinel firmware. Provides step-by-step instructions for installing the firmware.

To obtain the firmware update itself, please contact Qualis Audio.

>PDF format, 20 pages, 114 Kb, 22-Jul-2013

Sentinel Detailed 8-Page Brochure

Comprehensive product desription including detailed description of all features and capabilities, block diagrams, screen captures, connection diagrams, full technical specifications and ordering information.

>PDF format, 8 pages, revised 29-Sep-2010

Sentinel Quick Start Guide

Includes setup connection diagram and software settings description. All User Interface screens are described and examples of readings, displays, and graphical presentations shown.

>PDF format, 4 pages, 09-Feb-2011

Technical Notes

TechNote 1: Loudness Measurements and the CALM Act

The recent passage of the CALM act has made loudness management a major concern for broadcasters and those that supply them with programming and advertising. Most broadcasters and content creators understand that compliance will come at a cost, in capital expenditures, changes in their workflow and additional record keeping in the form of logs and reports. However, before investing in any equipment or process it is essential to understand the legislation and its likely implications. This note explains the CALM act and its ramifications, and suggests cost effective solutions to conformance issues.

>PDF format, 6 pages, revised 31-May-2011

TechNote 2: Understanding & Verifying Loudness Meters

Explains the ITU BS.1770 loudness measurement standard, how it has changed and how to verify that a loudness meter meets its requirements. Also see the accompanying Loudness Meter Test Suite.

>PDF format, 7 pages, revised 31-May-2011

TechNote 4: Loudness Variation When Downmixing

The loudness of surround format programs is generally assessed assuming they are reproduced in surround. Unfortunately, as explained in the technical note, program loudness may change considerably when reproduced in stereo.

>PDF format, 7 pages, revised 06-May-2013

TechNote 5: Quantitative Assessment of Surround Compatibility

A new method of downmix compatibility assessment has been invented by Qualis Audio. Its quantitative nature allows objective quality criteria to replace subjective interpretation of graphical displays. This document summarizes the hazards in downmixing and prior methods of assessment. It describes the new approach and its advantages, and show examples of its use.

>PDF format, 6 pages, revised 21-Apr-2013

TechNote 8: Automated Control of Loudness Measurements

Loudness measurements conforming to ITU BS.1770 must start and stop coincident with the beginning and end of the program or commercial being measured and be suspended when breaks occur in the program. The Sentinel provides this capability, and includes a mode which automatically measures both the program and interleaved commercials. This may be controlled manually through the browser interface, via logic level hardware inputs, or by software via the network interface. This note describes the control methods available for automated applications.

>PDF format, 4 pages, 13-Jul-2011

Loudness Meter Test Suite

Supplemental material for TechNote 2: Understanding & Verifying Loudness Meters. This test suite will be evolving – check back periodically for updates.

>WAV files in ZIP archive, 15.5 Mb, revised 12-May-2011

Papers & Articles

Loudness Monitoring
Broadcast Engineering, Feb 1, 2011

The ITU BS.1770 loudness measurement standard is changing. Here’s what you need to know.

By Richard Cabot and Ian Dennis

>HTML format

Automated Assessment of Surround Sound
Audio Engineering Society 127th Convention, New York, October 2009

The design of a real time electronic listener, optimized for surround sound program assessment, is described. Problems commonly encountered in surround audio production and distribution are automatically identified, including stereo/mono downmix compatibility, balance, metadata inconsistencies, channel interchange, loudness, excessive or inadequate level, and the presence of hum. Making measurements which correlate with audibility, displaying the results in a form easily understood by non-audio personnel created numerous design challenges. The technology used to solve these challenges, particularly that of downmix compatibility, are described.

>PDF format, 8 pages


Prism Sound / Qualis Audio Webinar: Is Your Loudness Meter Compliant?

Implications of the CALM Act. Delivered by Doug Ordon and Rich Cabot

>MP4 format, 152.4 Mb, 21-Apr-2011

What's Wrong With This Picture (and Sound)?
Common Problems with Program Masters

Heard of Gamut? Audio Phase? Dial-Norm? We’ll show video and audio examples of the most common problems that cause master tapes to be rejected at PBS. Through screen grabs of scopes and meters, and audio examples from actual shows, we’ll illustrate how to recognize them, how to avoid them and why it matters.

Presented at Public Television Quality Group workshops on Delivering High Quality HD Content to Viewers.

Presented at the Twin Cities Public Television Conference by Tim Mangini and Steve Scheel

>PowerPoint format, 31 pages, 6.7 Mb, 14-Jul-2010

Presented at the WGBH Public Television Conference by Tim Mangini and Jim Kutzner

>PowerPoint format, 31 pages, 6.6 Mb, 12-Nov-2010

Presented as PBS Quality Standards and Common Problems at the NET Public Television Conference by Terry Harvey, Tim Mangini, FRONTLINE/WGBH & Steve Scheel, PBS, Wendy Allen, PBS, Moderator

>PowerPoint format, 27 pages, 6.0 Mb, 13-Jan-2011

Standards & Regulation

The Commercial Advertisement Loudness Mitigation (CALM) Act

The CALM Act (H.R. 1084/S. 2847) legislation as passed by Congress and signed into law by the President. Certified by the Superintendent of Documents, US Government Printing Office.

>PDF format, 2 pages, 04-Dec-2011

FCC Report & Order adopting rules to implement the CALM Act

The FCC document specifying the rules adopted to implement the CALM Act legislation. The rules apply to digital TV broadcasters, digital cable operators, and other digital multichannel video programming distributors. They describe how the FCC will rely on a pattern of consumer complaints as an indication of possible noncompliance and cause for investigation, and the steps broadcasters must take to be deemed in compliance. For content passed through from producers, the rules also establish a “safe harbor” to establish compliance. The rules take effect on December 13, 2012.

>PDF format, 62 pages, 13-Dec-2011

FCC CALM Act Notice of Proposed Rulemaking

The FCC document describing their findings concerning implementation of the CALM Act legislation. Contains several dozen questions to industry and the public concerning implementation details, documentation requirements, forfeiture process and amounts, etc.

>PDF format, 37 pages, 27-May-2011

Qualis Audio’s Comments on the FCC CALM Act NPRM

Qualis Audio’s response to the FCC NPRM, containing suggestions for how to interpret phrases in the Act, what the FCC should require as evidence of compliance, how to handle complaints, how to implement forfeiture, etc.

>PDF format, 18 pages, 5-Jul-2011