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            <h1>Deesser</h1>
            <a href="images/Calf - Deesser.png" title="Calf - Deesser" class="thickbox"><img class="thumbnail" src="images/Calf - Deesser.png" /></a>
            <h2>Functionality</h2>
            <p>
                A Deesser is used to <strong>dynamically reduce high frequencies</strong>. The standard field of use is the reduction of "sssss" and "shhhh" in <strong>vocal tracks</strong>, that's where it's name came from. A deesser is mainly based on a compressor that reacts not on the full range signal but on a filtered sidechain signal. The signal is split in two different threads. The sidechain thread is sent through a filter, before it acts as a level for reducing the gain of the main thread. A deesser could also be used to reduce some high transients of a snaredrum or to bring some "air" in a sound without killing your tweeter on attack. So it may act as a <strong>creative effect</strong> just like a <strong>troubleshooter</strong>. But never compress a vocal track without adding a deesser afterwards - if you have a heart for your listeners.
            </p>
            <h2>Split mode</h2>
            <p>
                Calf Deesser is able to be driven in <strong>split mode</strong>. It means that not the full range signal will be affected by the gain reduction but only frequencies above the split frequency are manipulated in gain. Normally a wideband deesser sounds much cleaner on a single vocal track. But <strong>multitimbral vocal recordings</strong> could benefit a lot from this functionality. It also gives a great advantage for processing instrument tracks like strings for example. If you haven't understand it by now, think of a sidechain deesser like of a <strong>dynamically processing highshelf equalizer</strong>.
            </p>
            <h2>Tips</h2>
            <p>
                A neat special in the sidechain is the <strong>additional peak</strong>. Normally "sssss" and "shhhh" are dynamically far apart. With this bell filter you can <strong>accentuate or reduce significant frequencies</strong> to get the most precise control over your highs before they will reduce your main signal. The peak affects the sidechain signal but <strong>isn't added to the main signal's high band in split mode</strong>.
            </p><p>
                Male's "shhhh" typically is located around 3500-4000Hz, female's around 4000-4500Hz. Male's "ssss" is found around 4500-5000Hz, female's around 5000-5500Hz.
            </p><p>
                <strong>Main information about dynamic processing is located in the <a href="Compressor.html" title="Compressor">compressor</a> section. Additional information about sidechaining can be found in the <a href="Sidechain Compressor.html" title="Sidechain Compressor">sidechain compressor</a>'s section</strong>.
            </p>
            <h2>Controls</h2>
            <ul>
                <li><strong>Bypass:</strong> Don't process anything, just bypass the signal</li>
                <li><strong>Detected:</strong> This meter shows the level of the (filtered) signal which is used for detection</li>
                <li><strong>Gain Reduction:</strong> The level of reduction on the original signal</li>
                <li><strong>0dB:</strong> Flashes, if the signal rises about 0dB in the output stage</li>
                <li><strong>Active:</strong> Flashes, if the deesser detects a noticeable signal</li>
                <li><strong>S/C listen:</strong> Sends the sidechain (filtered) signal to the output for acoustical control</li>
                <li><strong>Detection:</strong> Choose if the deesser should take the exact signal for detection or an RMS like one (it's mainly smoother)</li>
                <li><strong>Mode:</strong> Select your operation mode between wideband or split</li>
                <li><strong>Threshold:</strong> If a signal rises above this level it will affect the gain reduction</li>
                <li><strong>Ratio:</strong> Set a ratio about which the signal is reduced. 1:2 means that if the level rises 4dB above the threshold, it will be only 2dB above after the reduction.</li>
                <li><strong>Laxity:</strong> The reaction of the deesser. Higher values won't affect really short peaks.</li>
                <li><strong>Makeup:</strong> Amplify your signal after processing. In split mode only the high band will be made up.</li>
                <li><strong>Split:</strong> The split frequency. All signals above this frequency will affect the gain reduction (and are affected in split mode, too)</li>
                <li><strong>Gain:</strong> It shifts the volume of the higher band. In wideband mode it affects the sidechain, in split mode it also affects the processed high frequencies.</li>
                <li><strong>Peak:</strong> Make a more precise selection of the sidechain signal with this bell</li>
                <li><strong>Level:</strong> Increase or decrease the chosen frequency</li>
                <li><strong>Peak Q:</strong> Set the quality of the bell. Higher values will affect a narrower, higher ones a wider band</li>
            </ul>
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