Hum Remover
The Hum Remover lets you get rid of “cycle hum” that may have been introduced into
your audio recording by power lines crossing your cables or by a shorted ground wire
in your setup. Hum from power sources generally sounds like a low buzzing and has a
frequency that corresponds to the electrical power in your country (for example,
countries in North America use 60 Hz AC power, whereas most countries in Europe
use 50 Hz power).
 Frequency: This slider lets you select the frequency of hum that this filter will attempt
to remove. Different countries use different power frequencies, so you need to
specify exactly what frequency to tune out. In general, most AC (alternating current)
operates at either 50 or 60 Hz.
 Q: This slider adjusts the filter resonance around the value of the Frequency slider.
Higher Q values result in a narrower but stronger resonance, which limits the
frequencies affected by the filter. If the important elements of your recording overlap
into the frequencies that are being filtered out, you might want to narrow the range
of frequencies affected.
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Part I
Audio Mixing
 Gain: This slider lets you set how much of the signal you’re attenuating. By default,
it’s set to the maximum value of –60 dB.
 Harmonics: These options allow you to attenuate additional frequencies that may be
introduced into your signal as a result of the primary cycle hum. These frequencies
are automatically derived by the filter, and you can specify up to five.