How to control the band equalizer

Question

Now I have some band:

self.eqFrequencies= @[ @32, @500, @1000, @2000, @4000, @8000, @16000 ];

I want to do it like:

_{(source: apple.com)}

I know that kAudioUnitSubType_NBandEQ:(A generalized N-band graphic EQ with specifiable filter types per-band). I need the frequency is divided into Wave band (range, 20 - 16000), and then control the gain of each Wave band.