you can learn a lot about it at http://www.tdpri.com/forum/amp-central-station/313889-peavey-wiggy-amp-designed-dweezil-zappa.html
but you can read a bit from the designer, Dweezil Zappa:
After "Music For Pets" I designed an amp with Peavey called "Wiggy." This became my main amp for a while. It was solid state with an interesting low mid frequency graphic eq circuit. Tonally it was very reminiscent of the Acoustic amp Frank used in the mid 70's alongside his Marshall. The Wiggy is what I used when I recorded with Lisa Loeb on "Cake And Pie." At that time my main guitar became an Ernie Ball Albert Lee model. I didn't realize the subliminal effect of his signature on my tele until the time I started playing his signature model EB! He also played a very memorable solo on "What The Hell Was I Thinking?" I did many recordings for film and television with my "Wiggy" rig. At that time I began to take a serious interest in recording and engineering. Certain types of amps and effects were being developed as smaller alternatives to big amps. There was a system by Lexicon called MPXG2 which had a 6 watt rack mounted amp along with a multi effects processor. I used this for a lot of sessions including the Britney Spears cover song "Hit Me Baby One More Time." I liked the idea of such a compact guitar rig option. At the time it was not a complete solution for every kind of tone though. I also used it and my Wiggy amps for the album "Automatic." The song Automatic featured an effect in a TC electronics G-Force box. The first time played with the effect I started recording the song. There's also a cool wide stereo effect from a short delay made by an old ADA multi efx 4. I've added that into different versions of rigs since then specifically for that doubling effect. It was in the 2009 ZPZ rig and the 2011 ZPZ rig. The guitar orchestration for "The Grinch" and "Hawaii 5-O" is all done with the Lexicon and some crafty eq from an Orban Parametric Equalizer. Next I started experimenting and recording more stuff in the studio without amps. I made some strange sounding recordings for textures on "What The Hell Was I Thinking?" by running into different distortion boxes and then directly into channel strips on the console. I used Native Instruments Guitar Rig for several projects and many overdubs on my "Go with What You Know" CD. At that time I was also in development for a tube version of the Wiggy amp with Peavey. They never went to market with it but I used the prototype on "Go With What You Know." The Tube Wiggy is most notably heard on Noitpure and the solo in Fighty Bitey.