I'm getting nearly identical frequency responses for reson and areson.  If I set iscl=1 the results are stranger still.  Am I doing something wrong?  Here are graphs of what I'm seeing:

graph #1:

ar rand .05

agreen=reson(ar,3000,1000,0)

ablue=areson(ar,3000,1000,0)

graph #2:

ar rand .5

agreen=reson(ar,3000,1000,1)

ablue=areson(ar,3000,1000,1)

I thought that the blue graph should have a dip where the green one has a peak.  Have I misunderstood something?