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		<title>User Manual</title>
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		<dc:creator><![CDATA[admin]]></dc:creator>
		<pubDate>Wed, 29 Jan 2025 18:49:10 +0000</pubDate>
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					<description><![CDATA[<p>Table des matières 2- Introduction 1 3- Microphone Management 2 4- Measurement with GPS-identified points 3 4-1- GPS Accuracy 4 4-2- Measurement Process 4 4-3- Erasing the measurement points 5 5- Measurement with Augmented Reality-identified points 6 5-1- Camera vs LiDAR 6 5-2- Measurement Process 6 5-3- Deleting the measurement...</p>
<p>The post <a href="https://jfd974programme.fr/user-manual/">User Manual</a> appeared first on <a href="https://jfd974programme.fr"></a>.</p>
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										<content:encoded><![CDATA[<p><a id="post-155-_Introduction"></a><a id="post-155-_Toc187765614"></a><a id="post-155-_Toc187763832"></a><br />
Table des matières</p>
<p><a href="#post-155-_Toc188556958">2- Introduction 1</a></p>
<p><a href="#post-155-_Toc188556959">3- Microphone Management 2</a></p>
<p><a href="#post-155-_Toc188556960">4- Measurement with GPS-identified points 3</a></p>
<p><a href="#post-155-_Toc188556961">4-1- GPS Accuracy 4</a></p>
<p><a href="#post-155-_Toc188556962">4-2- Measurement Process 4</a></p>
<p><a href="#post-155-_Toc188556963">4-3- Erasing the measurement points 5</a></p>
<p><a href="#post-155-_Toc188556964">5- Measurement with Augmented Reality-identified points 6</a></p>
<p><a href="#post-155-_Toc188556965">5-1- Camera vs LiDAR 6</a></p>
<p><a href="#post-155-_Toc188556966">5-2- Measurement Process 6</a></p>
<p><a href="#post-155-_Toc188556967">5-3- Deleting the measurement points. 11</a></p>
<p><a href="#post-155-_Toc188556968">6- Results Display 12</a></p>
<h1><a id="post-155-_Toc188556958"></a><strong>Introduction</strong></h1>
<h5><strong>The application called XXX allows you to generate heatmaps in the field of acoustics, in order to determine the sound coverage of a diffusion system. This feature covers all thirds of an octave, from 25 Hz to 16 kHz.</strong></p>
<p><strong>The principle is as follows: pink noise is generated in the broadcast system, and several measurement points are made in the listening area.</strong></p>
<p><strong>As a result, the user gets a heatmap for each third of an octave. The colour red represents the highest noise level, which is 0 dB. The colours follow a gradient from red to orange, yellow, green, to dark blue, which indicates the lowest sound level. The noise levels indicated are therefore relative.</strong></p>
<p><strong>It is important to note that the app is not used to measure the absolute level of sound, but to analyze its spatial distribution.</strong></h5>
<h5><img loading="lazy" class="wp-image-156"  alt="Avertissement contour" width="159" height="159" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/avertissement-contour.png"><br />
IMPORTANT:</h5>
<h5>To evaluate the coverage quality, the color is not enough, you must take into account the amplitude of the scale (difference between the maximum and minimum value of the level in dB).</h5>
<h5>So, a heatmap with a scale extending between -2dB and 0dB will always be better than a heatmap extending between -15dB and 0dB, whatever the colored pattern on the heatmap.</h5>
<h5>The main screen has 4 buttons:</h5>
<p><img class="wp-image-157"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-2.jpeg"></p>
<p>Access to the list of saved projects</p>
<p>Measurement with GPS-identified points</p>
<p>Microphone selection</p>
<p>Measurement with AR-identified points</p>
<p><strong>Picture 1</strong></p>
<h1><a id="post-155-_Toc188556959"></a>Microphone Management</h1>
<p>By default, the XXX app uses the iPhone&#8217;s microphone (Picture 2)</p>
<p>This method should be avoided because the microphone is medium quality, limited frequency response and holding the phone in the hand generates parasitic noises.</p>
<p><strong><img class="wp-image-158"  alt="Ampoule avec un remplissage uni" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni.png">NOTE: the internal microphone is located at the bottom of the iPhone.<br />
The microphone must be oriented towards the sound source during the measurement phases.</strong></p>
<p><img class="wp-image-159"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-4.jpeg"></p>
<p><strong>Picture 2</strong></p>
<p>It is strongly recommended to use a quality external microphone connected via USB-C or the lightning port.</p>
<p>This type of microphones is available from Audio-Technica, Shure, Sennheiser&#8230;</p>
<p>To use the outdoor microphone, connect to iPhone and then deselect &#8220;Internal Microphone&#8221; (Picture 3)</p>
<p><img class="wp-image-160"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-5.jpeg"></p>
<p><strong>Picture 3</strong></p>
<p>Access to the microphone must be allowed or, if applicable, an external microphone selected. Otherwise, the two buttons giving access to the measurement processes remains disabled (Picture 4).</p>
<h1><a id="post-155-_Toc187763834"></a><a id="post-155-_Toc187765616"></a><a id="post-155-_Toc188556960"></a>Measurement with GPS-identified points</h1>
<p>The measuring points are located by GPS.</p>
<p>This method is suitable for measuring large outdoor areas such as stadiums, sports fields with an accuracy ranging from 2 to 3 m.</p>
<p>Press the button</p>
<p><img class="wp-image-161"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-6.jpeg"></p>
<p>The following view appears:</p>
<p><img class="wp-image-162"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-7.jpeg"></p>
<p><strong>Picture 5</strong></p>
<p>If the internal microphone is selected, the view rotates 180° so that the microphone is oriented towards the source when the application is facing you.</p>
<p>(For information: The internal microphone used is located at the bottom of the phone)</p>
<h2><a id="post-155-_Toc187763835"></a><a id="post-155-_Toc187765617"></a><a id="post-155-_Toc188556961"></a>GPS Accuracy</h2>
<p>Before any measurement, make sure that the app can access the location, choose the &#8220;when the app is active&#8221; option when you first start the app.</p>
<p>Getting enough accuracy can take a few minutes, depending on the location.</p>
<p>An indicator at the top of the screen shows you the accuracy of the GPS</p>
<p>Accuracy greater than 5m: &#8220;Accuracy not ok&#8221;</p>
<p><img class="wp-image-163"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-8.jpeg"></p>
<p>Accuracy between 3 and 5 m: &#8220;Accuracy Poor&#8221;</p>
<p><img class="wp-image-164"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-9.jpeg"></p>
<p>Accuracy less than 3 m: &#8220;Accuracy OK&#8221;</p>
<p><img class="wp-image-165"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-10.jpeg"></p>
<p>Prefer &#8220;Accuracy Poor&#8221; at the very least.</p>
<h2><a id="post-155-_Toc187763836"></a><a id="post-155-_Toc187765618"></a><a id="post-155-_Toc188556962"></a>Measurement Process</h2>
<p>Position the microphone facing the sound source and press the button</p>
<p><img class="wp-image-166"  alt="An image containing text, screenshot, software, operating system

Auto-generated description" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/an-image-containing-text-screenshot-software-op.jpeg"></p>
<p>The recording begins and lasts about 2 seconds.</p>
<p><strong><img class="wp-image-167"  alt="Ampoule avec un remplissage uni" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-1.png">NOTE: Do not speak, do not make sudden gestures with the microphone, watch out for wind and drafts that can generate significant extraneous noise in the microphone and completely distort the measurements.</strong></p>
<p>Once the measurement is performed, the coordinates of the first point are displayed, it will always have the coordinates x= 0, y = 0 because it serves as the reference point.</p>
<p>The coordinates of the other measurement points will originate from the reference point. Move to the next point and repeat the measurement The coordinates of the recorded point are displayed after the measurement is made (Picture 6).</p>
<p><img class="wp-image-168"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-13.jpeg"></p>
<p><strong>Picture 6</strong></p>
<p>Repeat the measurement on as many points as necessary.</p>
<p>At a minimum, 5 measurement points are required to generate the heatmap.</p>
<h2><a id="post-155-_Toc188556963"></a>Erasing the measurement points</h2>
<p>Press this button to delete the last point and its associated audio recording :</p>
<p><img class="wp-image-169"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-14.jpeg"></p>
<p>A deletion confirmation message will be displayed.</p>
<p>Press this button to delete all points and associated audio recordings. A deletion confirmation message will be displayed.</p>
<p><img class="wp-image-170"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-15.jpeg"></p>
<p>Long press on the point you want to select, a context menu appears, tap on the &#8220;Trash&#8221; symbol. There is no deletion confirmation message.</p>
<p><img class="wp-image-171"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-16.jpeg"></p>
<h1><a id="post-155-_Toc188556964"></a>Measurement with Augmented Reality-identified points</h1>
<p>If the GPS signal is unavailable or the area is small, augmented reality can be used to define measurement points.</p>
<h2><a id="post-155-_Toc188556965"></a>Camera vs LiDAR</h2>
<p>LiDAR, available on iPhone Pro models from the iPhone 12, offers advantages over the camera for placing points on flat, uniform surfaces.</p>
<ul>
<li><strong>Surface Detection:</strong> The camera relies on textures and contrasts to detect surfaces, struggling with nearly uniform or monochrome surfaces, making accurate detection difficult.</li>
<li><strong>Precision:</strong> Unlike LiDAR, the camera estimates depth through algorithms, which can lead to errors, especially on flat, textureless surfaces.</li>
<li><strong>Lighting Sensitivity:</strong> The camera&#8217;s performance is affected by lighting conditions, making it less reliable in very bright or dark environments.</li>
<li><strong>Depth Accuracy:</strong> LiDAR uses laser pulses for direct distance measurement, offering better precision and performance in varying lighting.</li>
<li><strong>Motion Tracking:</strong> The camera may struggle with tracking if the device moves quickly or the surface lacks distinct visual markers.</li>
</ul>
<p>In summary, for flat, uniform surfaces, the camera is less accurate than LiDAR, which provides direct depth measurement and is more reliable in diverse conditions.</p>
<h2><a id="post-155-_Toc188556966"></a>Measurement Process</h2>
<p>Press the button:</p>
<p><img class="wp-image-172"  alt="Une image contenant texte, logo, symbole, Police

Description générée automatiquement" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/une-image-contenant-texte-logo-symbole-police.jpeg"></p>
<p>The following view appears:</p>
<p><img class="wp-image-173"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-18.jpeg"></p>
<p><strong>Picture 6</strong></p>
<p>Place a dot on the ground by touching the screen, the dot is represented by a stake surmounted by its number (Picture X).</p>
<p>If you are using an external microphone, place it directly above the marked point (Picture X).</p>
<p>If you are using the internal microphone, position the iPhone above the marked point, with the microphone facing the sound source.</p>
<p>If the internal microphone is selected, the view doesn’t rotate 180° so by default the microphone is not oriented towards the source when performing the measurement. Otherwise, it would be too difficult to place points.</p>
<p>(Note: the internal microphone is located at the bottom of the iPhone).</p>
<table>
<tbody>
<tr>
<td><img class="wp-image-174"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-19.jpeg"><strong>Picture 6</strong></td>
<td><img class="wp-image-175"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-20.jpeg"><strong>Picture 6</strong></td>
</tr>
</tbody>
</table>
<p>Press the button :</p>
<p><img class="wp-image-176"  alt="An image containing text, screenshot, software, operating system

Auto-generated description" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/an-image-containing-text-screenshot-software-op-1.jpeg"></p>
<p>The recording begins and lasts about 2 seconds (Figure XX).</p>
<p><strong><img class="wp-image-177"  alt="Ampoule avec un remplissage uni" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-2.png">NOTE: Do not speak, do not make sudden gestures with the microphone, watch out for wind and drafts that can generate significant extraneous noise in the microphone and completely distort the measurements.</strong></p>
<p><strong><img class="wp-image-178"  alt="Ampoule avec un remplissage uni" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-3.png">NOTE: When using Augmented Reality (AR) on an iPhone without LiDAR, surface detection can be challenging, especially in low light or complex environments.</strong></p>
<p><strong>Here are tips to improve AR performance:</strong></p>
<p><strong>Ensure proper lighting: </strong>Good lighting is essential for surface detection.<strong><br />
Use clear, textured surfaces</strong>: Textured surfaces help the app detect reference points more easily.</p>
<p><strong>Move the camera slowly: </strong>Slow, steady movements help the system analyze the surface better.</p>
<p><strong>Increase surface coverage: </strong>Move the phone closer or pan across the surface to give the camera more to analyze.</p>
<p><strong>Clean the camera lens: </strong>A clean lens ensures better image quality.<strong><br />
Avoid reflective surfaces: </strong>Glass and mirrors can confuse the AR system.<strong><br />
Recalibrate the phone’s position: </strong>Move the phone in a figure-eight motion to reset the system.</p>
<p><strong>Use AR features that don’t need surface detection: </strong>Some apps allow object placement in space without a surface.</p>
<p><strong>Update iOS and AR app: </strong>Ensure your software is up to date for optimal performance.<strong><br />
Restart the AR app: </strong>Reopening the app can help resolve issues</p>
<p><img class="wp-image-179"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-24.jpeg"></p>
<p><strong>Picture 6</strong></p>
<p>Place the second point by touching the screen (Figure XXX)</p>
<p><img class="wp-image-180"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-25.jpeg"></p>
<p><strong>Picture 6</strong></p>
<p>Then place the microphone next to the point and then run a new recording (Figure XXXX)</p>
<p><img class="wp-image-181"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-26.jpeg"></p>
<p><strong>Picture 6</strong></p>
<p><strong>Repeat the measurement at as many points as necessary (Figure XXXX)</strong></p>
<p><img class="wp-image-182"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-27.jpeg"></p>
<p><strong>Picture 6</strong></p>
<p>At least 5 measurement points are required.</p>
<h2><a id="post-155-_Toc188556967"></a>Deleting the measurement points.</h2>
<p>There are two ways to remove the dots:</p>
<p><img class="wp-image-183"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-28.jpeg"></p>
<p>Press this button to delete the last point and its associated audio recording.</p>
<p><img class="wp-image-184"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-29.jpeg"></p>
<p>Press this button to delete all points and associated audio recordings. A deletion confirmation message will be displayed.</p>
<h1><a id="post-155-_Toc188556968"></a>Results Display</h1>
<p>Press the button, it takes minimum 5 measurement points to enable the button.</p>
<p><img class="wp-image-185"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-30.jpeg"></p>
<p>The default view is displayed (Figure 7)</p>
<p><img class="wp-image-186"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-31.jpeg"></p>
<p><strong>Picture 7</strong></p>
<p>Selecting a third octave band between 25 and 16000 Hz.</p>
<p>0 dB represents the relative highest level for the selected third of an octave (dark red color).</p>
<p>The displayed scale is dynamic, and the values change depending on the octave band displayed.</p>
<p>The values in decibels represent a deviation from the maximum level referenced at 0dB for the displayed octave band. The values are relative, so calibration is not required.</p>
<p><img class="wp-image-187"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-32.png"></p>
<p><img class="wp-image-188"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-33.jpeg"></p>
<p>Automatically the scale is recalculated for each third octave band.</p>
<p><img class="wp-image-189"  alt="Avertissement contour" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/avertissement-contour-1.png"><br />
IMPORTANT:</p>
<p>To evaluate the coverage quality, the color is not enough, you must take into account the amplitude of the scale (difference between the maximum and minimum value of the level in dB).</p>
<p>So, a heatmap with a scale extending between -2dB and 0dB will always be better than a heatmap extending between -15dB and 0dB, whatever the colored pattern on the heatmap.</p>
<p><strong><img class="wp-image-190"  alt="Ampoule avec un remplissage uni" / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-4.png">NOTE:</strong></p>
<p><strong>As a reminder, SoundMeter 2D is not a sound level meter, it does not measure the sound level.</strong></p>
<p>The &#8220;Rotation&#8221; slider allows you to orient the view between -180° and + 180°. A double tap on the slider resets the rotation.</p>
<p>The X button<br />
<img class="wp-image-191"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-36.jpeg"><br />
gives access to the menu managing the heatmap display (Figure 8).</p>
<p><img class="wp-image-192"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-37.jpeg"></p>
<p>Picture 8</p>
<p>If you press the X button again<br />
<img class="wp-image-193"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-38.jpeg"><br />
, you return to the initial menu (Figure 9)</p>
<p><img class="wp-image-194"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-39.jpeg"></p>
<p><strong>Picture 9</strong></p>
<p>The Y button<br />
<img class="wp-image-195"  / loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-155-40.jpeg"><br />
recalls the default settings.</p>
<p>The post <a href="https://jfd974programme.fr/user-manual/">User Manual</a> appeared first on <a href="https://jfd974programme.fr"></a>.</p>
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		<title>SoundMeter 2D Tutorial</title>
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		<dc:creator><![CDATA[admin]]></dc:creator>
		<pubDate>Wed, 29 Jan 2025 18:44:34 +0000</pubDate>
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					<description><![CDATA[<p>&#160; Table des matières 2- Introduction 1 3- Microphone Management 2 4- Measurement with GPS-identified points 3 4-1- GPS Accuracy 4 4-2- Measurement Process 4 4-3- Erasing the measurement points 5 5- Measurement with Augmented Reality-identified points 6 5-1- Camera vs LiDAR 6 5-2- Measurement Process 6 5-3- Deleting the...</p>
<p>The post <a href="https://jfd974programme.fr/soundmeter-2d-tutorial/">SoundMeter 2D Tutorial</a> appeared first on <a href="https://jfd974programme.fr"></a>.</p>
]]></description>
										<content:encoded><![CDATA[
<p class="wp-block-paragraph">&nbsp;</p>



<p class="wp-block-paragraph">Table des matières</p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556958">2- Introduction 1</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556959">3- Microphone Management 2</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556960">4- Measurement with GPS-identified points 3</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556961">4-1- GPS Accuracy 4</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556962">4-2- Measurement Process 4</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556963">4-3- Erasing the measurement points 5</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556964">5- Measurement with Augmented Reality-identified points 6</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556965">5-1- Camera vs LiDAR 6</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556966">5-2- Measurement Process 6</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556967">5-3- Deleting the measurement points. 11</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556968">6- Results Display 12</a></p>



<h4 class="wp-block-heading"><a id="post-151-_Toc188556958"></a><strong>Introduction</strong></h4>



<p class="has-small-font-size wp-block-paragraph">The application called XXX allows you to generate heatmaps in the field of acoustics, in order to determine the sound coverage of a diffusion system. This feature covers all thirds of an octave, from 25 Hz to 16 kHz.</p>



<p class="has-small-font-size wp-block-paragraph">The principle is as follows: pink noise is generated in the broadcast system, and several measurement points are made in the listening area.</p>



<p class="has-small-font-size wp-block-paragraph">As a result, the user gets a heatmap for each third of an octave. The colour red represents the highest noise level, which is 0 dB. The colours follow a gradient from red to orange, yellow, green, to dark blue, which indicates the lowest sound level. The noise levels indicated are therefore relative.</p>



<p class="has-small-font-size wp-block-paragraph">It is important to note that the app is not used to measure the absolute level of sound, but to analyze its spatial distribution.</p>



<figure class="wp-block-image size-full is-resized"><img  alt="Avertissement contour" class="wp-image-270" style="width:75px;height:auto"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/avertissement-contour-5.png"></figure>



<p class="has-text-color has-link-color wp-elements-f10eaf41483287f254ca1454d3afba6f wp-block-paragraph" style="color:#f50707;font-size:16px">IMPORTANT:</p>



<p class="has-text-color has-link-color has-small-font-size wp-elements-6dc7edf446191d33ef7e1bf32716a652 wp-block-paragraph" style="color:#f50707">To evaluate the coverage quality, the color is not enough, you must take into account the amplitude of the scale (difference between the maximum and minimum value of the level in dB).<br>So, a heatmap with a scale extending between -2dB and 0dB will always be better than a heatmap extending between -15dB and 0dB, whatever the colored pattern on the heatmap.</p>



<p class="has-small-font-size wp-block-paragraph">The main screen has 4 buttons:</p>


<div class="wp-block-image">
<figure class="aligncenter"><img  alt="" class="wp-image-142"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/Picture-MainScreen-300x201.png"></figure>
</div>


<p class="has-text-align-center has-small-font-size wp-block-paragraph"><strong>Picture 1</strong></p>



<h4 class="wp-block-heading"><a id="post-151-_Toc188556959"></a><em>Microphone Management</em></h4>



<p class="has-small-font-size wp-block-paragraph">By default, the XXX app uses the iPhone&#8217;s microphone (Picture 2)</p>



<p class="has-small-font-size wp-block-paragraph">This method should be avoided because the microphone is medium quality, limited frequency response and holding the phone in the hand generates parasitic noises.</p>



<p class="has-text-color has-link-color wp-elements-b71e16f5264bdb87b0497205b342ca80 wp-block-paragraph" style="color:#f90606"><strong><img loading="lazy" class="wp-image-199"  alt="Ampoule avec un remplissage uni" width="70" height="70" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-5.png">NOTE: the internal microphone is located at the bottom of the iPhone.<br>The microphone must be oriented towards the sound source during the measurement phases.</strong></p>


<div class="wp-block-image">
<figure class="aligncenter is-resized"><img  alt="" class="wp-image-200" style="width:307px;height:auto"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-4.jpeg"></figure>
</div>


<p class="has-text-align-center wp-block-paragraph"><strong>Picture 2</strong></p>



<p class="wp-block-paragraph">It is strongly recommended to use a quality external microphone connected via USB-C or the lightning port.</p>



<p class="wp-block-paragraph">This type of microphones is available from Audio-Technica, Shure, Sennheiser&#8230;</p>



<p class="wp-block-paragraph">To use the outdoor microphone, connect to iPhone and then deselect &#8220;Internal Microphone&#8221; (Picture 3)</p>


<div class="wp-block-image">
<figure class="aligncenter"><img  alt="" class="wp-image-201"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-5.jpeg"></figure>
</div>


<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 3</strong></p>



<p class="wp-block-paragraph">Access to the microphone must be allowed or, if applicable, an external microphone selected. Otherwise, the two buttons giving access to the measurement processes remains disabled (Picture 4).</p>



<h1 class="wp-block-heading"><a id="post-151-_Toc187763834"></a><a id="post-151-_Toc187765616"></a><a id="post-151-_Toc188556960"></a>Measurement with GPS-identified points</h1>



<p class="wp-block-paragraph">The measuring points are located by GPS.</p>



<p class="wp-block-paragraph">This method is suitable for measuring large outdoor areas such as stadiums, sports fields with an accuracy ranging from 2 to 3 m.</p>



<p class="wp-block-paragraph">Press the button</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-202"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-6.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The following view appears:</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-203"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-7.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 5</strong></p>



<p class="wp-block-paragraph">If the internal microphone is selected, the view rotates 180° so that the microphone is oriented towards the source when the application is facing you.<br><br>(For information: The internal microphone used is located at the bottom of the phone)</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc187763835"></a><a id="post-151-_Toc187765617"></a><a id="post-151-_Toc188556961"></a>GPS Accuracy</h2>



<p class="wp-block-paragraph">Before any measurement, make sure that the app can access the location, choose the &#8220;when the app is active&#8221; option when you first start the app.</p>



<p class="wp-block-paragraph">Getting enough accuracy can take a few minutes, depending on the location.</p>



<p class="wp-block-paragraph">An indicator at the top of the screen shows you the accuracy of the GPS</p>



<p class="wp-block-paragraph"><br>Accuracy greater than 5m: &#8220;Accuracy not ok&#8221;</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-204"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-8.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Accuracy between 3 and 5 m: &#8220;Accuracy Poor&#8221;</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-205"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-9.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Accuracy less than 3 m: &#8220;Accuracy OK&#8221;</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-206"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-10.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Prefer &#8220;Accuracy Poor&#8221; at the very least.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc187763836"></a><a id="post-151-_Toc187765618"></a><a id="post-151-_Toc188556962"></a>Measurement Process</h2>



<p class="wp-block-paragraph">Position the microphone facing the sound source and press the button</p>



<figure class="wp-block-image"><img  alt="An image containing text, screenshot, software, operating system

Auto-generated description" class="wp-image-207"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/an-image-containing-text-screenshot-software-op-2.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The recording begins and lasts about 2 seconds.</p>



<p class="wp-block-paragraph"><strong><img class="wp-image-208"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-6.png">NOTE: Do not speak, do not make sudden gestures with the microphone, watch out for wind and drafts that can generate significant extraneous noise in the microphone and completely distort the measurements.</strong></p>



<p class="wp-block-paragraph">Once the measurement is performed, the coordinates of the first point are displayed, it will always have the coordinates x= 0, y = 0 because it serves as the reference point.</p>



<p class="wp-block-paragraph">The coordinates of the other measurement points will originate from the reference point. Move to the next point and repeat the measurement The coordinates of the recorded point are displayed after the measurement is made (Picture 6).</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-209"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-13.jpeg"></figure>



<p class="wp-block-paragraph"><br></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Repeat the measurement on as many points as necessary.</p>



<p class="wp-block-paragraph">At a minimum, 5 measurement points are required to generate the heatmap.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556963"></a>Erasing the measurement points</h2>



<p class="wp-block-paragraph">Press this button to delete the last point and its associated audio recording :</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-210"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-14.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">A deletion confirmation message will be displayed.</p>



<p class="wp-block-paragraph">Press this button to delete all points and associated audio recordings. A deletion confirmation message will be displayed.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-211"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-15.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Long press on the point you want to select, a context menu appears, tap on the &#8220;Trash&#8221; symbol. There is no deletion confirmation message.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-212"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-16.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<h1 class="wp-block-heading"><a id="post-151-_Toc188556964"></a>Measurement with Augmented Reality-identified points</h1>



<p class="wp-block-paragraph">If the GPS signal is unavailable or the area is small, augmented reality can be used to define measurement points.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556965"></a>Camera vs LiDAR</h2>



<p class="wp-block-paragraph">LiDAR, available on iPhone Pro models from the iPhone 12, offers advantages over the camera for placing points on flat, uniform surfaces.</p>



<ul class="wp-block-list">
<li><strong>Surface Detection:</strong> The camera relies on textures and contrasts to detect surfaces, struggling with nearly uniform or monochrome surfaces, making accurate detection difficult.</li>



<li><strong>Precision:</strong> Unlike LiDAR, the camera estimates depth through algorithms, which can lead to errors, especially on flat, textureless surfaces.</li>



<li><strong>Lighting Sensitivity:</strong> The camera&#8217;s performance is affected by lighting conditions, making it less reliable in very bright or dark environments.</li>



<li><strong>Depth Accuracy:</strong> LiDAR uses laser pulses for direct distance measurement, offering better precision and performance in varying lighting.</li>



<li><strong>Motion Tracking:</strong> The camera may struggle with tracking if the device moves quickly or the surface lacks distinct visual markers.</li>
</ul>



<p class="wp-block-paragraph">In summary, for flat, uniform surfaces, the camera is less accurate than LiDAR, which provides direct depth measurement and is more reliable in diverse conditions.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556966"></a>Measurement Process</h2>



<p class="wp-block-paragraph">Press the button:</p>



<figure class="wp-block-image"><img  alt="Une image contenant texte, logo, symbole, Police

Description générée automatiquement" class="wp-image-213"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/une-image-contenant-texte-logo-symbole-police-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The following view appears:</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-214"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-18.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Place a dot on the ground by touching the screen, the dot is represented by a stake surmounted by its number (Picture X).</p>



<p class="wp-block-paragraph">If you are using an external microphone, place it directly above the marked point (Picture X).</p>



<p class="wp-block-paragraph">If you are using the internal microphone, position the iPhone above the marked point, with the microphone facing the sound source.</p>



<p class="wp-block-paragraph">If the internal microphone is selected, the view doesn’t rotate 180° so by default the microphone is not oriented towards the source when performing the measurement. Otherwise, it would be too difficult to place points.</p>



<p class="wp-block-paragraph">(Note: the internal microphone is located at the bottom of the iPhone).</p>



<figure class="wp-block-table"><table class="has-fixed-layout"><tbody><tr><td>
<figure><img class="wp-image-215"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-19.jpeg"></figure><p></p>
<p><strong>Picture 6</strong></p>
</td><td>
<figure><img class="wp-image-216"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-20.jpeg"></figure><p></p>
<p><strong>Picture 6</strong></p>
</td></tr></tbody></table></figure>



<p class="wp-block-paragraph">Press the button&nbsp;:</p>



<figure class="wp-block-image"><img  alt="An image containing text, screenshot, software, operating system

Auto-generated description" class="wp-image-217"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/an-image-containing-text-screenshot-software-op-3.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The recording begins and lasts about 2 seconds (Figure XX).</p>



<p class="wp-block-paragraph"><strong><img class="wp-image-218"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-7.png">NOTE: Do not speak, do not make sudden gestures with the microphone, watch out for wind and drafts that can generate significant extraneous noise in the microphone and completely distort the measurements.</strong></p>



<p class="wp-block-paragraph"><strong><img class="wp-image-219"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-8.png">NOTE: When using Augmented Reality (AR) on an iPhone without LiDAR, surface detection can be challenging, especially in low light or complex environments.</strong></p>



<p class="wp-block-paragraph"><strong>Here are tips to improve AR performance:</strong></p>



<p class="wp-block-paragraph"><strong>Ensure proper lighting: </strong>Good lighting is essential for surface detection.<strong><br>Use clear, textured surfaces</strong>: Textured surfaces help the app detect reference points more easily.<br><br><strong>Move the camera slowly: </strong>Slow, steady movements help the system analyze the surface better.<br><br><strong>Increase surface coverage: </strong>Move the phone closer or pan across the surface to give the camera more to analyze.<br><br><strong>Clean the camera lens: </strong>A clean lens ensures better image quality.<strong><br>Avoid reflective surfaces: </strong>Glass and mirrors can confuse the AR system.<strong><br>Recalibrate the phone’s position: </strong>Move the phone in a figure-eight motion to reset the system.<br><br><strong>Use AR features that don’t need surface detection: </strong>Some apps allow object placement in space without a surface.<br><br><strong>Update iOS and AR app: </strong>Ensure your software is up to date for optimal performance.<strong><br>Restart the AR app: </strong>Reopening the app can help resolve issues</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-220"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-24.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Place the second point by touching the screen (Figure XXX)</p>



<p class="wp-block-paragraph"><img class="wp-image-221"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-25.jpeg"><br><br><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Then place the microphone next to the point and then run a new recording (Figure XXXX)</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-222"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-26.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph"><strong>Repeat the measurement at as many points as necessary (Figure XXXX)</strong></p>



<p class="wp-block-paragraph"><img class="wp-image-223"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-27.jpeg"><br><br><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">At least 5 measurement points are required.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556967"></a>Deleting the measurement points.</h2>



<p class="wp-block-paragraph">There are two ways to remove the dots:</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-224"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-28.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Press this button to delete the last point and its associated audio recording.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-225"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-29.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Press this button to delete all points and associated audio recordings. A deletion confirmation message will be displayed.</p>



<h1 class="wp-block-heading"><a id="post-151-_Toc188556968"></a>Results Display</h1>



<p class="wp-block-paragraph"><br>Press the button, it takes minimum 5 measurement points to enable the button.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-226"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-30.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The default view is displayed (Figure 7)</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-227"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-31.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 7</strong></p>



<p class="wp-block-paragraph">Selecting a third octave band between 25 and 16000 Hz.</p>



<p class="wp-block-paragraph">0 dB represents the relative highest level for the selected third of an octave (dark red color).</p>



<p class="wp-block-paragraph">The displayed scale is dynamic, and the values change depending on the octave band displayed.<br><br>The values in decibels represent a deviation from the maximum level referenced at 0dB for the displayed octave band. The values are relative, so calibration is not required.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-228"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-32.png"></figure>



<p class="wp-block-paragraph"></p>



<figure class="wp-block-image"><img  alt="" class="wp-image-229"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-33.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Automatically the scale is recalculated for each third octave band.</p>



<p class="wp-block-paragraph"><img class="wp-image-230"  alt="Avertissement contour" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/avertissement-contour-3.png"><br>IMPORTANT:</p>



<p class="wp-block-paragraph">To evaluate the coverage quality, the color is not enough, you must take into account the amplitude of the scale (difference between the maximum and minimum value of the level in dB).</p>



<p class="wp-block-paragraph">So, a heatmap with a scale extending between -2dB and 0dB will always be better than a heatmap extending between -15dB and 0dB, whatever the colored pattern on the heatmap.</p>



<p class="wp-block-paragraph"><strong><img class="wp-image-231"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-9.png">NOTE:</strong></p>



<p class="wp-block-paragraph"><strong>As a reminder, SoundMeter 2D is not a sound level meter, it does not measure the sound level.</strong></p>



<p class="wp-block-paragraph">The &#8220;Rotation&#8221; slider allows you to orient the view between -180° and + 180°. A double tap on the slider resets the rotation.</p>



<p class="wp-block-paragraph">The X button<br><img class="wp-image-232"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-36.jpeg"><br>gives access to the menu managing the heatmap display (Figure 8).</p>



<p class="wp-block-paragraph"><img class="wp-image-233"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-37.jpeg"><br><br>Picture 8</p>



<p class="wp-block-paragraph">If you press the X button again<br><img class="wp-image-234"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-38.jpeg"><br>, you return to the initial menu (Figure 9)</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-235"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-39.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 9</strong></p>



<p class="wp-block-paragraph">The Y button<br><img class="wp-image-236"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-40.jpeg"><br>recalls the default settings.</p>



<p class="wp-block-paragraph">&nbsp;</p>



<p class="wp-block-paragraph">Table des matières</p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556958">2- Introduction 1</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556959">3- Microphone Management 2</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556960">4- Measurement with GPS-identified points 3</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556961">4-1- GPS Accuracy 4</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556962">4-2- Measurement Process 4</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556963">4-3- Erasing the measurement points 5</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556964">5- Measurement with Augmented Reality-identified points 6</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556965">5-1- Camera vs LiDAR 6</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556966">5-2- Measurement Process 6</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556967">5-3- Deleting the measurement points. 11</a></p>



<p class="wp-block-paragraph"><a href="#post-151-_Toc188556968">6- Results Display 12</a></p>



<h1 class="wp-block-heading"><a id="post-151-_Toc188556958"></a><strong>Introduction</strong></h1>



<p class="wp-block-paragraph">The application called XXX allows you to generate heatmaps in the field of acoustics, in order to determine the sound coverage of a diffusion system. This feature covers all thirds of an octave, from 25 Hz to 16 kHz.</p>



<p class="wp-block-paragraph">The principle is as follows: pink noise is generated in the broadcast system, and several measurement points are made in the listening area.</p>



<p class="wp-block-paragraph">As a result, the user gets a heatmap for each third of an octave. The colour red represents the highest noise level, which is 0 dB. The colours follow a gradient from red to orange, yellow, green, to dark blue, which indicates the lowest sound level. The noise levels indicated are therefore relative.</p>



<p class="wp-block-paragraph">It is important to note that the app is not used to measure the absolute level of sound, but to analyze its spatial distribution.</p>



<p class="wp-block-paragraph"><img class="wp-image-237"  alt="Avertissement contour" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/avertissement-contour-4.png"><br>IMPORTANT:</p>



<p class="wp-block-paragraph">To evaluate the coverage quality, the color is not enough, you must take into account the amplitude of the scale (difference between the maximum and minimum value of the level in dB).</p>



<p class="wp-block-paragraph">So, a heatmap with a scale extending between -2dB and 0dB will always be better than a heatmap extending between -15dB and 0dB, whatever the colored pattern on the heatmap.</p>



<p class="wp-block-paragraph">The main screen has 4 buttons:</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-238"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-2-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Access to the list of saved projects</p>



<p class="wp-block-paragraph">Measurement with GPS-identified points</p>



<p class="wp-block-paragraph">Microphone selection</p>



<p class="wp-block-paragraph">Measurement with AR-identified points</p>



<p class="wp-block-paragraph"><strong>Picture 1</strong></p>



<h1 class="wp-block-heading"><a id="post-151-_Toc188556959"></a>Microphone Management</h1>



<p class="wp-block-paragraph">By default, the XXX app uses the iPhone&#8217;s microphone (Picture 2)</p>



<p class="wp-block-paragraph">This method should be avoided because the microphone is medium quality, limited frequency response and holding the phone in the hand generates parasitic noises.</p>



<p class="wp-block-paragraph"><strong><img class="wp-image-239"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-10.png">NOTE: the internal microphone is located at the bottom of the iPhone.<br>The microphone must be oriented towards the sound source during the measurement phases.</strong></p>



<figure class="wp-block-image"><img  alt="" class="wp-image-240"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-4-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 2</strong></p>



<p class="wp-block-paragraph">It is strongly recommended to use a quality external microphone connected via USB-C or the lightning port.</p>



<p class="wp-block-paragraph">This type of microphones is available from Audio-Technica, Shure, Sennheiser&#8230;</p>



<p class="wp-block-paragraph">To use the outdoor microphone, connect to iPhone and then deselect &#8220;Internal Microphone&#8221; (Picture 3)</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-241"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-5-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 3</strong></p>



<p class="wp-block-paragraph">Access to the microphone must be allowed or, if applicable, an external microphone selected. Otherwise, the two buttons giving access to the measurement processes remains disabled (Picture 4).</p>



<h1 class="wp-block-heading"><a id="post-151-_Toc187763834"></a><a id="post-151-_Toc187765616"></a><a id="post-151-_Toc188556960"></a>Measurement with GPS-identified points</h1>



<p class="wp-block-paragraph">The measuring points are located by GPS.</p>



<p class="wp-block-paragraph">This method is suitable for measuring large outdoor areas such as stadiums, sports fields with an accuracy ranging from 2 to 3 m.</p>



<p class="wp-block-paragraph">Press the button</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-242"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-6-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The following view appears:</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-243"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-7-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 5</strong></p>



<p class="wp-block-paragraph">If the internal microphone is selected, the view rotates 180° so that the microphone is oriented towards the source when the application is facing you.<br><br>(For information: The internal microphone used is located at the bottom of the phone)</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc187763835"></a><a id="post-151-_Toc187765617"></a><a id="post-151-_Toc188556961"></a>GPS Accuracy</h2>



<p class="wp-block-paragraph">Before any measurement, make sure that the app can access the location, choose the &#8220;when the app is active&#8221; option when you first start the app.</p>



<p class="wp-block-paragraph">Getting enough accuracy can take a few minutes, depending on the location.</p>



<p class="wp-block-paragraph">An indicator at the top of the screen shows you the accuracy of the GPS</p>



<p class="wp-block-paragraph"><br>Accuracy greater than 5m: &#8220;Accuracy not ok&#8221;</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-244"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-8-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Accuracy between 3 and 5 m: &#8220;Accuracy Poor&#8221;</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-245"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-9-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Accuracy less than 3 m: &#8220;Accuracy OK&#8221;</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-246"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-10-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Prefer &#8220;Accuracy Poor&#8221; at the very least.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc187763836"></a><a id="post-151-_Toc187765618"></a><a id="post-151-_Toc188556962"></a>Measurement Process</h2>



<p class="wp-block-paragraph">Position the microphone facing the sound source and press the button</p>



<figure class="wp-block-image"><img  alt="An image containing text, screenshot, software, operating system

Auto-generated description" class="wp-image-247"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/an-image-containing-text-screenshot-software-op-4.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The recording begins and lasts about 2 seconds.</p>



<p class="wp-block-paragraph"><strong><img class="wp-image-248"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-11.png">NOTE: Do not speak, do not make sudden gestures with the microphone, watch out for wind and drafts that can generate significant extraneous noise in the microphone and completely distort the measurements.</strong></p>



<p class="wp-block-paragraph">Once the measurement is performed, the coordinates of the first point are displayed, it will always have the coordinates x= 0, y = 0 because it serves as the reference point.</p>



<p class="wp-block-paragraph">The coordinates of the other measurement points will originate from the reference point. Move to the next point and repeat the measurement The coordinates of the recorded point are displayed after the measurement is made (Picture 6).</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-249"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-13-1.jpeg"></figure>



<p class="wp-block-paragraph"><br></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Repeat the measurement on as many points as necessary.</p>



<p class="wp-block-paragraph">At a minimum, 5 measurement points are required to generate the heatmap.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556963"></a>Erasing the measurement points</h2>



<p class="wp-block-paragraph">Press this button to delete the last point and its associated audio recording :</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-250"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-14-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">A deletion confirmation message will be displayed.</p>



<p class="wp-block-paragraph">Press this button to delete all points and associated audio recordings. A deletion confirmation message will be displayed.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-251"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-15-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Long press on the point you want to select, a context menu appears, tap on the &#8220;Trash&#8221; symbol. There is no deletion confirmation message.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-252"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-16-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<h1 class="wp-block-heading"><a id="post-151-_Toc188556964"></a>Measurement with Augmented Reality-identified points</h1>



<p class="wp-block-paragraph">If the GPS signal is unavailable or the area is small, augmented reality can be used to define measurement points.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556965"></a>Camera vs LiDAR</h2>



<p class="wp-block-paragraph">LiDAR, available on iPhone Pro models from the iPhone 12, offers advantages over the camera for placing points on flat, uniform surfaces.</p>



<ul class="wp-block-list">
<li><strong>Surface Detection:</strong> The camera relies on textures and contrasts to detect surfaces, struggling with nearly uniform or monochrome surfaces, making accurate detection difficult.</li>



<li><strong>Precision:</strong> Unlike LiDAR, the camera estimates depth through algorithms, which can lead to errors, especially on flat, textureless surfaces.</li>



<li><strong>Lighting Sensitivity:</strong> The camera&#8217;s performance is affected by lighting conditions, making it less reliable in very bright or dark environments.</li>



<li><strong>Depth Accuracy:</strong> LiDAR uses laser pulses for direct distance measurement, offering better precision and performance in varying lighting.</li>



<li><strong>Motion Tracking:</strong> The camera may struggle with tracking if the device moves quickly or the surface lacks distinct visual markers.</li>
</ul>



<p class="wp-block-paragraph">In summary, for flat, uniform surfaces, the camera is less accurate than LiDAR, which provides direct depth measurement and is more reliable in diverse conditions.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556966"></a>Measurement Process</h2>



<p class="wp-block-paragraph">Press the button:</p>



<figure class="wp-block-image"><img  alt="Une image contenant texte, logo, symbole, Police

Description générée automatiquement" class="wp-image-253"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/une-image-contenant-texte-logo-symbole-police-2.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The following view appears:</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-254"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-18-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Place a dot on the ground by touching the screen, the dot is represented by a stake surmounted by its number (Picture X).</p>



<p class="wp-block-paragraph">If you are using an external microphone, place it directly above the marked point (Picture X).</p>



<p class="wp-block-paragraph">If you are using the internal microphone, position the iPhone above the marked point, with the microphone facing the sound source.</p>



<p class="wp-block-paragraph">If the internal microphone is selected, the view doesn’t rotate 180° so by default the microphone is not oriented towards the source when performing the measurement. Otherwise, it would be too difficult to place points.</p>



<p class="wp-block-paragraph">(Note: the internal microphone is located at the bottom of the iPhone).</p>



<figure class="wp-block-table"><table class="has-fixed-layout"><tbody><tr><td>
<figure><img class="wp-image-255"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-19-1.jpeg"></figure><p></p>
<p><strong>Picture 6</strong></p>
</td><td>
<figure><img class="wp-image-256"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-20-1.jpeg"></figure><p></p>
<p><strong>Picture 6</strong></p>
</td></tr></tbody></table></figure>



<p class="wp-block-paragraph">Press the button&nbsp;:</p>



<figure class="wp-block-image"><img  alt="An image containing text, screenshot, software, operating system

Auto-generated description" class="wp-image-257"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/an-image-containing-text-screenshot-software-op-5.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The recording begins and lasts about 2 seconds (Figure XX).</p>



<p class="wp-block-paragraph"><strong><img class="wp-image-258"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-12.png">NOTE: Do not speak, do not make sudden gestures with the microphone, watch out for wind and drafts that can generate significant extraneous noise in the microphone and completely distort the measurements.</strong></p>



<p class="wp-block-paragraph"><strong><img class="wp-image-259"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-13.png">NOTE: When using Augmented Reality (AR) on an iPhone without LiDAR, surface detection can be challenging, especially in low light or complex environments.</strong></p>



<p class="wp-block-paragraph"><strong>Here are tips to improve AR performance:</strong></p>



<p class="wp-block-paragraph"><strong>Ensure proper lighting: </strong>Good lighting is essential for surface detection.<strong><br>Use clear, textured surfaces</strong>: Textured surfaces help the app detect reference points more easily.<br><br><strong>Move the camera slowly: </strong>Slow, steady movements help the system analyze the surface better.<br><br><strong>Increase surface coverage: </strong>Move the phone closer or pan across the surface to give the camera more to analyze.<br><br><strong>Clean the camera lens: </strong>A clean lens ensures better image quality.<strong><br>Avoid reflective surfaces: </strong>Glass and mirrors can confuse the AR system.<strong><br>Recalibrate the phone’s position: </strong>Move the phone in a figure-eight motion to reset the system.<br><br><strong>Use AR features that don’t need surface detection: </strong>Some apps allow object placement in space without a surface.<br><br><strong>Update iOS and AR app: </strong>Ensure your software is up to date for optimal performance.<strong><br>Restart the AR app: </strong>Reopening the app can help resolve issues</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-260"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-24-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Place the second point by touching the screen (Figure XXX)</p>



<p class="wp-block-paragraph"><img class="wp-image-261"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-25-1.jpeg"><br><br><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">Then place the microphone next to the point and then run a new recording (Figure XXXX)</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-262"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-26-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 6</strong></p>



<p class="wp-block-paragraph"><strong>Repeat the measurement at as many points as necessary (Figure XXXX)</strong></p>



<p class="wp-block-paragraph"><img class="wp-image-263"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-27-1.jpeg"><br><br><strong>Picture 6</strong></p>



<p class="wp-block-paragraph">At least 5 measurement points are required.</p>



<h2 class="wp-block-heading"><a id="post-151-_Toc188556967"></a>Deleting the measurement points.</h2>



<p class="wp-block-paragraph">There are two ways to remove the dots:</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-264"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-28-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Press this button to delete the last point and its associated audio recording.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-265"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-29-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Press this button to delete all points and associated audio recordings. A deletion confirmation message will be displayed.</p>



<h1 class="wp-block-heading"><a id="post-151-_Toc188556968"></a>Results Display</h1>



<p class="wp-block-paragraph"><br>Press the button, it takes minimum 5 measurement points to enable the button.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-266"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-30-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">The default view is displayed (Figure 7)</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-267"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-31-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 7</strong></p>



<p class="wp-block-paragraph">Selecting a third octave band between 25 and 16000 Hz.</p>



<p class="wp-block-paragraph">0 dB represents the relative highest level for the selected third of an octave (dark red color).</p>



<p class="wp-block-paragraph">The displayed scale is dynamic, and the values change depending on the octave band displayed.<br><br>The values in decibels represent a deviation from the maximum level referenced at 0dB for the displayed octave band. The values are relative, so calibration is not required.</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-268"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-32-1.png"></figure>



<p class="wp-block-paragraph"></p>



<figure class="wp-block-image"><img  alt="" class="wp-image-269"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-33-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph">Automatically the scale is recalculated for each third octave band.</p>



<p class="wp-block-paragraph"><img class="wp-image-270"  alt="Avertissement contour" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/avertissement-contour-5.png"><br>IMPORTANT:</p>



<p class="wp-block-paragraph">To evaluate the coverage quality, the color is not enough, you must take into account the amplitude of the scale (difference between the maximum and minimum value of the level in dB).</p>



<p class="wp-block-paragraph">So, a heatmap with a scale extending between -2dB and 0dB will always be better than a heatmap extending between -15dB and 0dB, whatever the colored pattern on the heatmap.</p>



<p class="wp-block-paragraph"><strong><img class="wp-image-271"  alt="Ampoule avec un remplissage uni" loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/ampoule-avec-un-remplissage-uni-14.png">NOTE:</strong></p>



<p class="wp-block-paragraph"><strong>As a reminder, SoundMeter 2D is not a sound level meter, it does not measure the sound level.</strong></p>



<p class="wp-block-paragraph">The &#8220;Rotation&#8221; slider allows you to orient the view between -180° and + 180°. A double tap on the slider resets the rotation.</p>



<p class="wp-block-paragraph">The X button<br><img class="wp-image-272"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-36-1.jpeg"><br>gives access to the menu managing the heatmap display (Figure 8).</p>



<p class="wp-block-paragraph"><img class="wp-image-273"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-37-1.jpeg"><br><br>Picture 8</p>



<p class="wp-block-paragraph">If you press the X button again<br><img class="wp-image-274"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-38-1.jpeg"><br>, you return to the initial menu (Figure 9)</p>



<figure class="wp-block-image"><img  alt="" class="wp-image-275"/ loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-39-1.jpeg"></figure>



<p class="wp-block-paragraph"></p>



<p class="wp-block-paragraph"><strong>Picture 9</strong></p>



<p class="wp-block-paragraph">The Y button<br><img class="wp-image-276"  loading="lazy" decoding="async" src="https://jfd974programme.fr/wp-content/uploads/2025/01/word-image-151-40-1.jpeg"><br>recalls the default settings.</p>
<p>The post <a href="https://jfd974programme.fr/soundmeter-2d-tutorial/">SoundMeter 2D Tutorial</a> appeared first on <a href="https://jfd974programme.fr"></a>.</p>
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