I've used a variety of devices to get the harmonizer affect. Back when we recorded Elastic, I was using a multieffects processor called the DP4 (I think). It had a pitch shifter algorithm that I could program to produce a pitch an octave below the one I was playing, or two pitches an octave and a fifth below, etc. It worked OK in the beginning, but I soon realized that the sound quality and tracking were pretty poor, so I switched to using a vintage Eventide H3000. The Eventide sounded better, but it was pretty fragile and got banged up on the road. After going through two of those units, and realizing that I really needed to travel lighter (overweight charges were killing us!), I started using a Digitech Whammy Pedal. It sounded good, the only disadvantage being that I could only produce one pitch shifted voice at a time (so no more octave and fifths.) I've discovered that, like most things in music, saxophone effects will always be a work in progress. I have to say that right now I'm really enjoying my break from the world of buttons, knobs, cables, pedals, LEDs, MIDI, instruction manuals and the like. With acoustic trio, I can just focus on playing the saxophone again. That's hard enough in itself!