# 28-Band Graphic Equalizer in Matlab

I'm trying to design a MATLAB audio player that includes something like a 31-band equalizer. Right now I have the filters working by using the FIR1() function to create an FIR bandpass filter at each frequency specified on the bands. This is great except that it's not exactly what I'm wanting to do. I want to either boost or cut the desired frequency, not isolate the frequency.

How would I go about using these FIR filters in parallel to boost or cut the signal instead of just isolating the signal?