Eric R's List: Recording

• The first thing to notice is that the cutoff point is not actually where the gain reduction starts. This is because the definition of the cutoff point of a filter is that point at which there is 3dB of gain reduction, and this is worth bearing in mind when using any filtering — even though the controls of the filter may indicate that gain reduction is only happening within a certain frequency zone, there will almost always be some gain change outside this zone as well.
• CUTOFF FREQUENCY: the frequency at which a high-pass or low-pass filter has attenuated the signal by 3dB.
• FILTER SLOPE: the gain change per octave of a high-pass or low-pass filter.
• SWEPT FILTER: any filter which allows the user control over its characteristic frequency.

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• ‘Peak Reduction’
• you get more compression (more reduction of peak levels) as you crank the knob.
• Input Gain
• difference is that as you compress with a Compression or Peak Reduction control (or a Threshold control), the overall processed sound tends to reduce in level, while with the Input Gain approach the overall signal level gets louder

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• Reducing volume in software is basically equivalent to reducing the bit depth
• Attenuating a signal is done by multiplying each sample by a number less than one, with the result being that you're no longer using the full resolution to describe the audio, resulting in reduced dynamic range and signal-to-noise ratio