allpass band bandpass bandreject bass bend biquad chorus channels compand contrast dcshift deemph delay dither divide downsample earwax echo echos equalizer fade fir firfit flanger gain highpass hilbert input ladspa loudness lowpass mcompand noiseprof noisered norm oops output overdrive pad phaser pitch rate remix repeat reverb reverse riaa silence sinc spectrogram speed splice stat stats stretch swap synth tempo treble tremolo trim upsample vad vol