Orban Loudness Meter User Manual

Orban Loudness Meter

for Windows and macOS

OPERATING MANUAL

2019 February (version 2.9.7)

V2.7 was a major upgrade that added support for up to 7.1-channel

surround and the ability to analyze audio and the audio parts of video files

offline for their BS.1770-4 Integrated Loudness, EBU R 128 LRA, highest

tur peak level, and number of true peaks above 0 dBFS. The meter will

graph the BS.1770-4 Integrated Loudness and peak swings of the CBS

Loudness Meter as a function of time, and can display a histogram of the

BS.1770-4 Integrated Loudness.

v2.9 is now available for both Windows and Mac. Windows V2.9 works

with Windows Vista/7/8/10; It is not compatible with Windows XP and

earlier. We will continue to make v2.0 available for Windows XP users.

Mac V2.9.7 works with macOS 10.14 Mojave and some earlier versions.

Orban makes this software available free of charge, subject to the

provisions of the License Agreement displayed by the software installer.

This software is sponsored by Orban’s loudness controllers for FM radio,

television, and streaming. We invite users who need highest-performance

automatic loudness control to check out the Optimod models 1101e,

6300, 5700i, 8600Si, 8600, 8700i and 8685 at:

http://www.orban.com

and Optimod-PCn 1600 audio processing software for Intel/Windows at

https://www.indexcom.com/products/optimodpcn/

If you have a previous version of the meter installed, a successful

installation may require your doing more than just running the setup

executable. Please follow the installation instructions in the Installation

section starting on page 9.

Revision History

Version 1.0.0 was the original public beta release.

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Version 1.0.1:

 Reduces CPU load caused by refreshing the meter’s display. This

allows slower computers to operate at the meter’s maximum 100

Hz refresh rate, minimizing flicker.

 Changes the color scheme to improve appearance and to make

the meters easier to read.

 Changes the graphic design of the single-bar meter display

elements like peak hold to make them easier to read and to

prevent them from being obscured.

 On startup, checks whether the computer’s CPU supports the

SSE2 instruction set and exits gracefully if it does not.

 Increase the gain of the VU meter by 10 dB for a given setting of

the VU Meter Gain control. When the control is set to 0 dB and the

meter is fed by a sinewave, the VU meter will now display the

same level as the absolute peak meter.

 Clarifies the readme (this document) to better explain how the

meter interacts with your computer’s sound device(s).

 Moves the Audio Input selector to the Settings page.

Version 1.0.2:

 Causes the meters to be reset when disabled.

 In computers running Windows 2000, the software now gives the

correct result when testing whether the computer’s CPU supports

the SSE2 instruction set.

Version 1.0.3:

 To reduce CPU load and allow more versatile scaling of the

loudness meter window, V1.0.3 uses Windows DirectDraw and

requires DirectX 7 or higher to run.

Version 2.0.3:

 Is available for Macs running OS X10.6 and higher.

 Supports both the ITU BS.1770-1 and BS.1770-4 standards, user

selectable. BS.1770-4 adds gating to the previous BS.1770-1

standard so that the meter ignores silence and is weighted toward

louder program material, which contributes most to a listener’s

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perception of loudness. BS.1770-4 indicates only sounds that fall

within a floating window that extends from the loudest sounds

within the preset integration period to sounds that are 10 dB

quieter than the loudest sounds.

 Supports EBU R 128 measurements. R 128 calls for three meters:

an ungated “momentary” meter having a time integration window

of 400 ms, an ungated “short-term” meter having a time

integration window of 3 seconds, and an “integrated” meter,

having a user-selectable time integration window and gating as

specified in BS.1770-4.

The Orban application provides a dedicated meter for the

“momentary” indication while indicating the “short-term” and

“integrated” loudness on a second meter, where a yellow bar

displays the short-term loudness and a single cyan segment

indicates the integrated loudness. A numerical display of the

integrated loudness appears to the right of the meter.

The Orban meter implements the “loudness range” measurement

per EBU – TECH 3342, which is incorporated into R 128 by

reference. The “loudness range” measurement is most commonly

used in Manual Mode to assess the dynamic range of entire

program segments.

EBU – TECH 3341 calls for two selectable meter scales and two

selectable ranges. The scales are either absolute (in units of LUFS

or LKFS, which are the same) or are relative with respect to a

user-selectable reference level (which usually corresponds to the

program’s Dolby Digital® dialnorm metadata value [in dB] and

whose units of measure are LU or LK, which are the same). ATSC

A/85, Annex K (“Requirements for Establishing and Maintaining

Audio Loudness of Commercial Advertising in Digital Television

When Using Non-AC-3 Audio Codecs”) and EBU – TECH 3344

(“Practical guidelines for distribution systems in accordance with

EBU R 128”) provide instructions on how to choose the reference

level in systems that do not use Dolby Digital to convey the

program to the consumer.

The ATSC A/85 2011, ITU-R BS.1770-4, and various EBU R 128-

related documents are available as free downloads and can easily

be located with a search engine.

 Allows manual start/stop operation of the meter per BS.1770-4.

 Extends the maximum integration period to three hours for both

program monitoring and manual modes. This allows the meter to

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measure the integrated loudness and LRA of most long-form

program material such as feature films.

 Changes the scale of the CBS Loudness Meter to match the scale

of the EBU meters. This allows the readings of the BS.1770 and

CBS meters to be compared easily. In addition, it changes the

scaling of the “CBS Loudness Gain” control so that +10 dB on the

V1 meter is equivalent to “0 dB” on the V2 meter.

 Supports Annex 2 of ITU-R Rec. BS.1770-4 (“Considerations for

accurate peak metering of digital audio signals”) by adding a

peak-reading meter with a sample rate of 384 kHz and a recovery

characteristic that is the same as a PPM, which we chose

arbitrarily to make the meter easy to read.

This “Reconstructed Peak” meter indicates the peak value of the

signal following D/A conversion (including the reconstruction filter)

with an accuracy of better than 0.2 dB, assuming that this signal

path has constant group delay and a low frequency cutoff low

enough to avoid introducing tilt into the waveform. This meter

indicates “intra-sample peaks,” which can cause clipping in the

analog section of a playback device even if the magnitude of the

digital samples is constrained to 0 dBFS. This is a serious problem

with many popular playback devices.

Assuming that the D/A converter and reconstruction filter in a

playback device have constant group delay and that response in

the analog signal path is flat to DC, the worst-case overshoot is

+3 dBFS, as exemplified by a sinewave whose frequency is 25%

of the sampling frequency and where the samples are taken 45

degrees before and after the zero-crossings of the sinewave. If the

“Reconstructed Peak” meter indicates higher than 0 dBFS, this

indicates that clipping will occur in many playback devices.

The Orban meter does not implement the optional “HF pre-

emphasis” and “DC block” blocks in the block diagram in Section 2

of Annex 2 of the BS.1770-4 standard. This is because the choice

of pre-emphasis and DC blocking frequency characteristics is

completely arbitrary, attempting to compensate for non-constant

group delay and DC blocking that may or may not exist in the

analog signal path of a given target playback device and which

may or may not cause analog clipping from low frequency tilt even

if they do exist.

See https://www.indexcom.com/whitepaper/zerodbfsplus/ for a

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more detailed discussion of intersample peaks.

 Oversamples the PPM attack time processing to 384 kHz. This

allows the meter to match the attack characteristics of EBU Tech.

3205-E more closely because this standard was originally

developed for analog meters that are measuring analog signals.

 Permits the important meter readings to be logged into a comma-

delimited text file that can be imported into any spreadsheet or

graphing program for further analysis and display. The sample

period of the log file is user adjustable via the “Logging Interval”

control.

 Adds support for the Microsoft WASAPI Loopback Interface

(Windows Vista and 7/8 only). WASAPI Loopback eliminates the

requirement for a sound device to support Wave I/O or what is

traditionally called “Stereo Mix” to play and record/monitor files

played through Windows Audio.

 Fixes a bug that caused the sample peak meter to indicate the

values of positive-going peaks incorrectly.

 Extends the VU Gain control range to +20 dB. This allows the VU

meter to be aligned to SMPTE (–20 dBFS) or EBU (–18 dBFS) line-

up level.

Version 2.0.6:

 Fixes a bug where the LRA display would not reset if the 1770

meter is reset while paused.

 Adds Reset and Pause/Resume buttons for the LRA readout.

 Limits LRA readout to BS.1770-4 mode.

 Changed the clamping range for the BS.1770-4 long-term

integrated readout to -70 LK on the lower bound, with no upper

bound.

 Hides the refresh rate slider in Windows Vista/7/8. It is still

displayed for Windows XP and Mac OS X.

 Fixes a potential race condition in the wave input code where the

flags field was not being explicitly cleared in each wave buffer

header.

Version 2.0.8:

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 Adds support for ASIO devices. Note that to feed the Orban meter

while connected to another application, a given ASIO device must

have a “multi-client” driver, which many ASIO devices do not

have.

 Adds a “Channels” drop-down, which allows you to choose which

audio channels the Loudness Meter monitors when a given sound

device supports more than two channels.

Version 2.7.6:

 Adds support for up to 7.1-channel surround.

 Adds support for offline, faster-than-real-time file analysis.

 Removes support for Windows XP and does not yet support the

Mac OS.

 Corrects a bug that caused the integration time of the BS.1770-4

Short-Term meter to be less than 3 seconds.

Version 2.7.8:

 Corrects a bug that caused the BS.1770 Integrated Loudness to

be indicated incorrectly in the Analysis tab.

 Corrects a bug that could cause the number of reconstructed

peaks above 0 dBFS to be miscounted in the Analysis tab.

Version 2.8.0:

 Corrects a bug that caused the graph of BS.1770 Integrated

Loudness in the Analysis tab to show the progress of the whole-

file loudness integration process (i.e. the computation of the

number shown in the BS.1770 Integrated Loudness box). Instead

of tracking the localized loudness over time, this bug caused the

graph to converge on the value of the whole-file Integrated

Loudness at the right graph margin.

V2.8.0 displays the BS.1770 loudness as a function of time, using

the value of the BS.1770 Integration Time control to set the time

constant of the loudness integrator. The loudness graph is delayed

with respect to the time-domain waveform by an amount equal to

the integration time, and this lag may cause the loudness and

time domain waveforms to be slightly misaligned graphically when

long integration times are used.

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Note that if you change the value of the BS.1770 Integration Time

control, the graph for a given file will not be recalculated unless

you force a recalculation by quitting and restarting the Loudness

Meter application, or by removing and then restoring the filename

from the left window.

 Corrects a bug that prevented BS.1770-2+ Integration Time

settings of greater than 60 seconds from being saved and restored

when quitting and then restarting the meter application. The

maximum allowable integration time depends on the 1770 mode.

The meter now checks the mode and limits the maximum time to

60 seconds in -1 mode and to three hours in -2+ mode.

Version 2.8.2 (for Windows):

 Updates the LRA measurement to conform to EBU – TECH 3342

2015-03-25 DRAFT REVISION. This revision clarifies certain

ambiguities in the original published LRA algorithm.

Version 2.8.3 (for Windows):

 Corrects a bug that caused the meter to be incorrectly drawn on

the screen when Windows Text Size was not set to “100%.”

Version 2.8.5 (for macOS):

 Makes the meter compatible with macOS 10.12 Sierra and earlier

macOS versions, and updates the feature set for the Mac version.

Version 2.8.8 (for Windows):

 Corrects several bugs introduced in v2.8.3 (Windows build) due to

a build error, including inaccuracies and missing data in the

Analysis window, and potential instability on some systems.

Version 2.8.9 (for Windows and macOS):

 Windows: Corrects a bug where installations of V2.8.3 and higher

did not show the “ITU BS.1770 integrated” loudness in the

analysis tab. The cyan graph was incorrectly drawn in black and

the numeric value was not visible. This bug only occurred if V2.8.2

or earlier had not been previously installed on the computer.

 macOS: Makes the feature set of the macOS version the same as

the Windows version and unifies the Windows and macOS version

numbers.

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Version 2.9.0 (for Windows):

 Automatically implements the “invisible ‘ITU BS.1770 integrated’

loudness” bug fix from v2.8.9 without requiring the Orban audio

loudness meter.properties file to be deleted manually. (macOS

v2.8.9 does not require this fix, so there is no v2.9.0 for macOS.)

Version 2.9.5 (for Windows and MacOS):

 Modifies the oversampling algorithm in the True Peak level

calculation.

 Corrects the peak level calculation in the MacOS version.

 Disables the vertical UI layout in the Windows version.

Version 2.9.6 (for Windows and MacOS):

 For Analysis, replaces the existing MP3 decoder with an MP3

decoder capable of decoding a wider variety of files.

 (MacOS only) Corrects a bug that was causing the CBS loudness

algorithm to produce incorrect values that were about 16 dB too

low. The Mac version now agrees with the Windows version.

Version 2.9.7 (for MacOS):

 For Analysis, corrects a bug that caused the analysis to crash with

certain compressed files in MacOS 10.14.

Windows Hardware and Operating System
Requirements

 Microsoft Windows® Vista (SP1 or greater), or 7/8/10.

 Windows DirectX 7 or higher installed.

 1.5 GHz or faster Intel or Intel-compatible processor that

implements the SSE2 instruction set. Note that this is a function of

the processor, not the operating system.

http://en.wikipedia.org/wiki/SSE2

 1024x768 or larger display.

 70 megabytes of free RAM in which to run the application.