Filter axemasters Richard Patrick and Geno Lenardo are both Fender guitar purists, but they're also big fans of the Line 6 POD, and of their Amp Farm software, which generates digital models of classic amps. "If you want a Vox AC30 sound or a 1968 Fender Twin, you can dial it up," Lenardo explains. "Some of them sound really good and some of them are like, [heavy sarcasm] 'Yeah, that sounds just like it.' But they're all there. You can mix and match different heads and cabinets." As for Patrick, he's a self described meat-and-potatoes guitarist. He uses a Marshal JMP-1 preamp, a Marshal stack with Celestion Greenback speakers, and a 3200 power amp. He also employs an Eventide DSP4000, which effectively eliminates the need for any other effects. We recently talked shop with the duo about their tuning and playing techniques, and their obsession with feedback.