Hello Shaun123, Phase adjust the amount of lag or lead one signal has in reference to another. Frequency is an adjustment of the number of cycles pers second a signal will produce. Gain refers to the amplification factor of a signal. now in reference to you amplifier by changing phase you can set the delay of a signal (if used right you can make a wicked reverb effect), but setting phase normally will affect the tones Frequency will affect for bass and treble functionality Gain will both preset and provide amplitude adjustment (volume) Take into mind these are more then likely presets. I hope this helps
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