The PEQ1R is a 4-band equalizer that provides 2 mid bands of parametric equalization control with adjustments for filter bandwidth (Q ), filter center frequency, cut or boost level, as well as cut or boost for bass and treble. 4-band equalizer. 2 full parametric bands. Center frequency control. Q bandwidth control. Gain control. Bass and Treble control. Bypass switch. Unbalanced input with low priority. Gradual fade back from mute for unbalanced input.