There's nothing new about a guitar pedal designed to sound like an organ's rotating speaker, but Line 6 has kept things traditional and authentic with the Roto-Machine.
The controls are more like those on a real rotary speaker than on most of the guitar simulations. Three classic rotary speakers are modelled here: two from Leslie and one from Fender.
Each one has fast and slow rotation speeds with independent speed controls; you toggle between the two speeds with the dual-action footswitch.
The drive control adds overdrive to the sound, while the blend control balances the sounds of the (emulated) horn and drum for extra authenticity. Finally, the three-position ramp switch allows you to adjust how quickly the rotation speed moves from high to low (or vice versa) when you hit the footswitch.
We'll be honest - we're suckers for a nice Leslie sound. Within just a few minutes of experimentation, we managed to get close to Stevie Ray Vaughan's sound on Cold Shot, Charlie Hunter's smoother guitar sound and played some classic B3 licks with the drive control maxed out.
You don't just have to play pseudo-organ sounds, though; The Beatles, among many others, used rotary speakers on clean guitar parts, just as we've come to use chorus.
The Roto-Machine is great for shimmering ambient chordal sounds, and the stereo outputs add a wonderful feeling of space to these sounds.