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<h1>Gate</h1>
<a href="images/Calf - Gate.png" title="Calf - Gate" class="thickbox"><img class="thumbnail" src="images/Calf - Gate.png" /></a>
<h2>Functionality</h2>
<p>
A gate is mainly used to <strong>reduce lower parts of a signal</strong>. This kind of signal processing reduces disturbing noise between useful signals.
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<h2>Basics and controls</h2>
<p>
Gating is done by detecting the volume below a chosen level ("<strong>Threshold</strong>") and divide it by the factor set with "<strong>Ratio</strong>". The bottom of the noise floor is set via Max Gain Reduction. Because an exact manipulation of the signal would cause distrotion of the waveform the reduction can be levelled over the time. This is done by setting "Attack" and "Release".
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"<strong>Attack</strong>" determines how long the signal has to fall below the threshold before any reduction will occur and "<strong>Release</strong>" sets the time the signal has to raise above the threshold to reduce the reduction again. Shorter signals than the chosen attack time will be left untouched.
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<h2>Line graph</h2>
<p>
The line graph shows exactly what your gate is doing at the moment. <strong>The x-axis shows the input level and the y-axis</strong> displays the output. <strong>The dot</strong> represents the actual level of the detected signal. Here you can see exactly how much your audio is reduced.
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<h2>Examples and Tips</h2>
<p>
When it comes down to modern music production todays listeners are used to you need to compress and limit the signal which brings unwanted noise to the foreground. For example compressing the toms of a drumset raises every other signal the microphone received inbetween the hits on the drum. This may be disturbing even without compression so it's useful to reduce the unwanted signals from the particular track. It may be useful to reduce the resonating sound of openly tuned drums as well and make the signal shorter and more "direct".
</p><p>
A gate is mainly a <a href="Compressor.html" title="Compressor">compressor</a> in "upside down" mode so understanding the level detection via attack and release inside a compressor is useful to get an understanding of the procedure inside a gate.
</p><p>
If your source contains a <strong>complex waveform</strong> and you want the gate to react on a defined range of frequencies choose a <a href="Sidechain Gate.html" alt="Calf - Sidechain Gate">sidechain gate</a> to process the sidechain signal which is used for level detection first.
</p><p>
If you want to reduce the noise with different settings in different bands perhaps the <a href="Multiband Gate.html" title="Multiband Gate">Multiband Gate</a> could be your choice.
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<h2>Controls</h2>
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<li><strong>Bypass:</strong> Don't process anything, just bypass the signal</li>
<li><strong>Input (VU-meter):</strong> The level of the original signal</li>
<li><strong>Input (LED):</strong> Flashes if the level of the original signal raises above 0dB (it doesn't clip your signal)</li>
<li><strong>Output (VU-meter):</strong> The level of the compressed and made up signal</li>
<li><strong>Output (LED):</strong> Flashes if the level of the output signal raises above 0dB (it may clip your signal depending on your host and your systems' bitrate!)</li>
<li><strong>Max Gain Reduction:</strong> The level of gain reduction when the signal is below the threshold</li>
<li><strong>Gating:</strong> The level of reduction on the original signal</li>
<li><strong>Attack:</strong> Amount of milliseconds the signal has to rise above the threshold before gain reduction stops</li>
<li><strong>Release:</strong> Amount of milliseconds the signal has to fall below the threshold before the reduction is increased again</li>
<li><strong>Knee:</strong> Curve the sharp knee around the threshold to enter gain reduction more softly</li>
<li><strong>Ratio:</strong> Set a ratio about which the signal is reduced</li>
<li><strong>Threshold:</strong> If a signal rises above this level the gain reduction is released</li>
<li><strong>Makeup:</strong> Amplify your signal after processing</li>
<li><strong>Stereo Link:</strong> Choose if the average level between both channels or the louder channel affects the reduction</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>
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