2 The Loudness Analyzer & Normalizer is a tool that is useful at the
3 end of the mixing process to make the final audio file comply with
4 different specs regarding loudness.
8 It is enabled by checking
9 <kbd class="option">Enable master-bus output gain control</kbd> in the
10 <a href="@@preferences#preferences-mixer">Preferences</a>.
11 The <a href="@@master-bus-strip">Master Bus strip</a> then shows a <kbd class="menu">LAN</kbd>
12 button to start the analysis, and a volume slider that is the global gain
13 that can be set either manually or by the loudness normalizer.
16 The LAN can also be started from the <kbd class="menu">Session > Loudness
17 assistant…</kbd> menu. If the option above is not enabled, Ardour
18 will link to the relevant page of the Preferences.
21 <p>Either method show the following window:</p>
24 <img src="/images/pre_loudness.png" alt="The Loudness Analyzer realtime selector">
26 The Loudness Analyzer realtime selector
31 This window allows to start the loudness analysis. A choice is offered
32 between freewheeling (i.e. Ardour renders the session as fast as possible
33 to measure the loudness), by default, or Realtime, for cases where freewheeling would
34 not accurately render the session, e.g. if a hardware or JACK effect
35 is used in the session, by clicking on the <kbd class="menu">Realtime</kbd>
40 After the analysis is over, the Loudness Analyzer and Normalizer is shown:
44 <img src="/images/loudness_analyzer.png" alt="The Loudness Analyzer and Normalizer">
46 The Loudness Analyzer and Normalizer
50 <h2>The Loudness Graph</h2>
53 At the top of the window, a loudness graph visually represents the
54 analysis. The x-axis represents the time, and the y-axis represents
55 the perceived loudness in <abbr title="Loudness Units referenced to
56 Full Scale">LUFS</abbr>:
60 <li><span style="color:green;">Integrated loudness</span> averaging the loudness on the whole session</li>
61 <li><span style="color:red;">Short loudness</span> using a sliding time window of 3 seconds</li>
62 <li><span style="color:blue;">Momentary loudness</span> using a sliding time window of 400 ms.</li>
65 <h2>Normalization Parameters</h2>
68 As loudness is a perceived sonic energy, and depends on the level, frequency,
69 duration and nature of the sound, this window allows to base the calculation
70 of the loudness normalization on different parameters :
73 <li><dfn>Peak :</dfn> is the highest signal level value</li>
74 <li><dfn>True Peak :</dfn> is the highest signal level value where the
75 signal has been oversampled to figure out more in-between values
76 between the samples (interpolation)</li>
77 <li><dfn>Integrated Loudness :</dfn> is the loudness computed from the
78 whole session or range</li>
79 <li><dfn>Max Short Loudness :</dfn> is the maximum loudness computed
80 on short time ranges (3 seconds)</li>
81 <li><dfn>Max Momentary Loudness :</dfn> is the maximum momentary loudness</li>
84 Any combination of these parameters can be taken into account when determining
85 the gain normalization, by checking its momentary button, and setting a
86 <em>Target</em> value.
89 Ardour shows both the <em>Measured</em> value of the parameters, and the
90 <em>Delta</em> value, i.e. the difference between the <em>Target</em>
91 and <em>Measured</em> values, hence the gain correction.
94 The maximum <em>Delta</em> value is the Gain correction to apply to fit
95 all the Target values.
98 Ardour shows, under the parameters, a summary of the calculation :
101 <li><dfn>Gain to normalize:</dfn> is the max <em>Delta</em> value</li>
102 <li><dfn>Previous output gain:</dfn> is the current Master track gain</li>
103 <li><dfn>Total Gain:</dfn> is the difference between these two values,
104 hence the correction to apply</li>
110 A selection of presets is offered to simplify the normalization. These
111 presets apply the relevant parameters and their target values. Below
112 is a table of these presets:
116 <tr><th>Parameter name: </th><th>dbFS </th><th>dBTP </th><th>LUFS </th><th>short</th><th>mom. </th><th>FS</th><th>TP </th><th>int</th><th>sht </th><th>mom</th><th>maxIntg</th><th>notes</th></tr>
119 <tr><th>EBU R128 </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-1.0</td><td>-23</td><td> 0</td><td> 0</td><td>-22.5</td><td> -23.5</td></tr>
120 <tr><th>EBU R128 S1 </th><td>false</td><td> true</td><td> true</td><td> true</td><td>false</td><td> 0</td><td>-1.0</td><td>-23</td><td>-18</td><td> 0</td><td>-22.5</td><td> -23.5</td></tr>
121 <tr><th>ATSC A/85 </th><td>false</td><td> true</td><td> true</td><td> true</td><td>false</td><td> 0</td><td>-2.0</td><td>-24</td><td> 0</td><td> 0</td><td>-22.0</td><td> -26.0</td></tr>
122 <tr><th>AES Streaming </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-1.0</td><td>-18</td><td> 0</td><td> 0</td><td>-16.0</td><td> -20.0</td></tr>
123 <tr><th>ASWG-R001 HOME </th><td>false</td><td> true</td><td> true</td><td> true</td><td>false</td><td> 0</td><td>-1.0</td><td>-24</td><td> 0</td><td> 0</td><td>-22.0</td><td> -26.0</td></tr>
124 <tr><th>Digital Peak </th><td> true</td><td>false</td><td>false</td><td>false</td><td>false</td><td> 0</td><td> 0.0</td><td> 0</td><td> 0</td><td> 0</td><td> 0.0</td><td>-200.0</td></tr>
125 <tr><th>CD/DVD </th><td> true</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-0.1</td><td> -9</td><td> 0</td><td> 0</td><td> 0.0</td><td>-200.0</td></tr>
127 <tr><th>Amazon Music </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-2.0</td><td>-14</td><td> 0</td><td> 0</td><td> -9.0</td><td> -19.0</td></tr>
128 <tr><th>Apple Music </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-1.0</td><td>-16</td><td> 0</td><td> 0</td><td>-15.0</td><td> -17.0</td></tr>
129 <tr><th>Deezer </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-1.0</td><td>-15</td><td> 0</td><td> 0</td><td>-14.0</td><td> -16.0</td></tr>
130 <tr><th>Soundcloud </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-1.0</td><td>-10</td><td> 0</td><td> 0</td><td> -8.0</td><td> -13.0</td></tr>
131 <tr><th>Spotify </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-1.0</td><td>-14</td><td> 0</td><td> 0</td><td> -8.0</td><td> -20.0</td></tr>
132 <tr><th>Spotify Loud </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-2.0</td><td>-11</td><td> 0</td><td> 0</td><td> -5.0</td><td> -17.0</td></tr>
133 <tr><th>Youtube </th><td>false</td><td> true</td><td> true</td><td>false</td><td>false</td><td> 0</td><td>-1.0</td><td>-14</td><td> 0</td><td> 0</td><td>-13.0</td><td> -15.0</td></tr>
138 New presets can be created at will and saved/removed using the <kbd>Save</kbd>
139 and <kbd>Remove</kbd> buttons next to the preset choice. The Standard
140 presets listed above can not be removed or edited.
144 The <kbd>Analysis Report</kbd> button allows to visually represent
145 the analysis with a graph in a very similar window to the one in the
146 Post-<a href="@@export-dialog">Export</a> analysis.
149 <h2>The Conformity Analysis Panel</h2>
153 At the lower right end of the window is a <em>Conformity Analysis</em>
154 info panel indicating, for each of the presets above, if the corrected
155 gain would fit the required values:
158 <li><span style="color:red;">✖</span>: the signal is too loud</li>
159 <li><span style="color:orange;">✔</span>: the signal is too quiet, but satisfies the max. loudness spec</li>
160 <li><span style="color:green;">✔</span>: signal loudness is within the spec.</li>
164 Lastly, the gain correction is, by default, applied after all the processors
165 of the master bus. This can also be changed, either by checking the
166 <kbd>Custom Amplifier Position</kbd> temporaty button in this window, or in the Master
167 strip, by <kbd class="mouse">Right</kbd>-clicking the gain slider and
168 checking <kbd class="option">Custom LAN Amp Position</kbd>. The gain
169 normalizer then becomes a processor in the processors box of the Master
170 strip, that can be moved as needed like any processor/effect.