Well, last night was the first time I had my new iamp200 and Wizzy out with "the band." Naturally, I had it cranked higher than I did when I was fiddling with it at home. I noticed that if I grab the E-string and wiggle it, the speaker cone moves with large excursions in response. That is, the cone was following movements of 3-5 Hz or so. Okay, so I don't wiggle my strings when I play but this very low frequency response manifests itself as substantial cone movement each time my finger is placed on a string in the natural course of playing. John at EA confirmed that the iamp has no infrasonic filter. He suggested I use the lowest band of EQ to cut the very lowest octave. That won't do as I use that band for slight boost! By the way, I tried a similar test with my old Behringer BX-1200 bass workstation. No such cone movement occurs. Can any of you recommend an outboard infrasonic filter? FYI-- I am using the Revolution Solo pickup P.S.-- Yes, "infrasonic" which refers to those frequencies below those in the audible range (sound) as opposed to "subsonic" which means below the speed of sound.