Loudness Pilot

Quick start

From an unknown level to a file that meets the spec.

The window

Numbers on top, the last minute in the middle, the controls below.

Header

The preset bar (previous, next, the list, SAVE), the power button (bypass) and the menu (three lines) with this manual. Click the logo for the version and credits.

Readouts

Integrated (wide), Short-term, Momentary, Range, True peak and Input. See The readouts.

Graph

The last 60 seconds of loudness round the target, with the leveller's gain and the limiter's reduction in a strip under it. See The graph.

Target

The loudness to aim for and the true-peak ceiling.

Auto Level

The leveller, with its switch in the card's title: Speed, Range and Gate.

Output

Gain, the limiter switch, TRIM TO TARGET, RESET and Reset on play.

Tooltip strip

Along the bottom: what the control under the mouse does.

Signal flow

Measure, level, trim, limit, measure again.

The input is measured first (the Input readout). The leveller takes that measurement every 100 ms and sets its gain from it, then Gain is added, then the limiter keeps the true peaks under the Ceiling. Everything else on screen measures what comes out at the end: what your listeners will hear.

The limiter looks 2 ms ahead, so the audio is delayed by that much (plus a few samples), on or off. The host is told and compensates. The measurements follow ITU-R BS.1770 and EBU R128, as the streaming services and broadcasters use them.

The readouts

Six numbers, coloured by how they sit against the target.

Integrated

The loudness of everything since the last reset, gated as EBU R128 does it (silence and pauses don't pull it down). This is the number delivery specs talk about. Under it: on target (within 1 LU), or how many LU too loud or too quiet. Its colour says the same: the accent on target, red too loud, blue too quiet.

Short-term

The loudness of the last 3 seconds, and the highest it has been since the reset.

Momentary

The loudness of the last 400 ms, and its highest.

Range

How much the loudness varies (LRA, EBU Tech 3342), once there are 3 seconds or more to judge. Speech usually sits between 3 and 8 LU; under it, Even, Dynamic (over 6 LU) or Very dynamic (over 10 LU).

True peak

The highest peak since the reset, between samples too, as a decoder will see it. It turns red when it went over the ceiling.

Input

The integrated loudness of what comes in, before the leveller, the gain and the limiter, with its short-term loudness under it. Compare it with Integrated to see how much Loudness Pilot moved.

RESET (in the Output card) starts Integrated, Range, True peak and the maximums over.

The graph

The last minute, round the target.

Time runs from right (now) to left (a minute ago). The vertical scale is centred on the target: 12 LU above it and 24 below, with a line every 6 LU labelled in LUFS and the target drawn as a band across the graph.

Momentary

The filled area: the loudness of each 400 ms, jumping with every word or beat.

Short-term

The bright line: the loudness of the last 3 seconds, the one to keep near the target band.

Gain strip

Under the graph, ±12 dB round 0. The green line is the leveller's gain (LEVELLER, with its current value); red bars down from the top are the limiter's reduction (LIMITER). Frequent red bars mean the limiter is working hard: lower Gain or the Target.

Target

Where it has to land.

Target

The integrated loudness to aim for: Apple Podcasts −16, Spotify and YouTube −14, mono podcasts −19, EBU R128 −23 LUFS. The readouts, the graph, TRIM TO TARGET and the leveller all work towards it. −30 … −10 LUFS

Ceiling

The highest true peak allowed out; the limiter keeps peaks under it. −1 dBTP suits most services; audiobooks often ask for −3. −9 … 0 dBTP

Auto Level

An engineer on the fader, for speech.

Switch it on with the On pill in the card's title. The leveller listens to the input's momentary loudness, keeps a slow average of it and sets the gain that brings that average to the target. A soft speaker comes up, a loud one goes down, and the integrated loudness stays close to the target before any trim. Its gain glides between steps, so it never clicks. With it off, its gain glides back to 0 dB and the three knobs grey out.

Speed

How many seconds the leveller listens back before it moves the gain. Short follows every phrase; long only rides big changes, like a new speaker. It turns down four times faster than it turns up, as a compressor would. 0.5 … 10 s

Range

The most it may turn up or down. 1 … 24 dB

Gate

Under this loudness (pauses, breaths, room noise) it holds its gain instead of turning silence up. Raise it in a noisy room. −70 … −30 LUFS

Output

Trim, limit and measure.

Gain

Added after the leveller, before the limiter. TRIM TO TARGET sets it for you. −24 … +24 dB

True-peak limiter

Keeps peaks, between samples too, under the Ceiling. It looks 2 ms ahead, so the gain is already down when a peak arrives, and recovers smoothly (120 ms). Off, the audio is still delayed by the same amount, so switching it never moves the timing.

TRIM TO TARGET

Sets Gain so the integrated loudness lands on the target, then starts the measurement over. It needs a measurement first: play the whole programme, or a typical stretch of it.

RESET

Starts the integrated, range and peak measurements over.

Reset on play

Starts the measurement over whenever the host starts playing, so a bounce or a take is measured from its start.

Presets

The delivery standards, and the same with the leveller riding.

Press SAVE in the header to keep your own. The preset menu has Save As, Delete and Open Folder. An asterisk after the preset's name means you've changed something since loading it. Every control is a host parameter and can be automated.

Recipes

Starting points for common jobs.

Specifications

The numbers.