Of all the analog effects painstakingly emulated through the magic of digital signal processing (DSP), perhaps none is as difficult to nail as the swirl and warble of a rotary speaker cabinet. It’s easy to understand why. Unlike, say, an analog fuzz, which is merely another tone-altering circuit between your guitar and amp, the rotary speaker is practically a living, breathing thing at the speaking end of your signal chain—an organic combination of machine and moving air that’s exceedingly difficult to imitate with a computer chip and mounted speaker.
Rotary speaker cabs have the distinction of being immensely impractical too. The largest and most powerful specimens are hefty enough to justify the use of a small forklift. And even more manageably sized units like Fender’s Vibratone are still potential maintenance nightmares—if you can find a solid working unit at all. This conundrum leaves a lot of players lusting for the authentically wobbly sounds of Pink Floyd’s “Us and Them” arpeggios, Stevie Ray Vaughan’s queasy and chugging “Cold Shot,” or George Harrison’s funky Let It Be tones between a rock and a hard place. But if Neo Instruments Ventilator rotary cabinet simulator is any indication, DSP technology—aided by some very inspired and obsessive engineers—has taken another important step in bridging the gap.
Spinning While Sitting Still
A lot of manufacturers had a go at rotary speaker manufacturing in the ’60s and ’70s. Fender’s Vibratone (a derivative of the Leslie 16) was among the most successful, finding favor with the Beatles, and more recently, Heartbreaker Mike Campbell. Odd brands like Cordovox, Elka, and Dynacord, to name a few, also made very cool sounding rotary cabinets that have found their way onto records ever since. But none are more legendary than the Leslie—the original rotary speaker cabinet, built for use with the Hammond organ, and adopted by guitarists in the mid ’60s. The Neo Ventilator is modeled after one of the most famous Leslies of all, the 122, which features a tube amplifier section, woofer and treble speakers, and most importantly a cylindrical lower rotor that disperses the woofer’s output, and two spinning horns that distribute sound from the treble speaker.
For anyone who has lugged a Leslie (never but never return your keyboard player’s call when he tells you he’s moving his Hammond), the compact dimensions of the 2-pound, 7-ounce Ventilator alone make it worth a look. But while the German-made Ventilator is small and light, it feels about as rugged as an old wood-cabinet Leslie. The enclosure is all aluminum and thoughtfully designed with recessed knobs that are well out of the way of errant boots, and the unit’s high-quality switches for selecting bypass and Slow/Fast modes feel especially precise.
The knobs themselves control five parameters that can drastically modify the sound in strikingly realistic ways. A Speed knob increases or decreases virtual rotation speed from the basic Slow and Fast modes. The very cool Acceleration knob slows or increases the rate at which the rotation spools up—mimicking the mechanical properties of a real rotary cabinet motor. The Balance knob adjusts the relative volume of the virtual lower rotor (for bass tones) and rotating horn (which produces treblier tones). Drive approximates the tube overdrive of a Leslie amplifier. And Distance, which really affects the rotary simulation’s intensity, simulates a range of microphone placements relative to the rotors.
The rear panel includes stereo outputs, as well as a Remote jack for the optional Ventilator Remote footswitch, which lets you stop the effect in a manner similar to a single-speed Leslie. There’s also a Key/ Git (keyboard/guitar) switch. Switched to Key, it replicates the frequency response of a Leslie 122, while in the 6-string-optimized Git mode, the output is more linear and has less signal coloration.
Let it Whirl
A real rotary speaker can color sound in ways that range from subtle to extreme. I was interested in exploring the musical potential of the Ventilator in a quieter setting for my first tests, so I placed it between a 15-watt Vox Pathfinder amp and a DeArmond Jet Star and Martin 00-15 with L.R. Baggs iBeam electronics. With the Martin out front, faster modulations more commonly associated with Leslies sometimes sounded a bit alien and out of scale. But a slow setting and distant virtual microphone placement lent a beautiful, dynamic, and dreamy texture to minor, open-tuned fingerstyle acoustic sections— a cool, if unorthodox application of the rotary speaker sound.
The Jet Star and Ventilator were a more obvious match. And though a small amp and speaker can be a major obstacle to authentic rotary cabinet sounds, the Ventilator still sounded incredibly deep and rich—both in slow and fast settings—particularly when I emphasized low-end content with the balance knob. In a small room, there was still something almost odd about hearing such a rich swirl in the absence of a hulking, monolithic Leslie cabinet. But it’s remarkable how convincing this emulation can sound on tape—all with a rig you can fit in a gig bag and whatever free hand you can spare to carry a little tube amp.
To really experience how good the Ventilator sounds, it’s good to go big. Rotary speakers are incredibly effective at stretching and shifting time and space. And those aspects of the Ventilator’s performance are best experienced with the assist of volume and dimension. To get them, I ran one output from the Ventilator into a 35-watt Vox TB35C2 Bruno, ran a second output into a Fender Vibroverb, and placed the amps about six feet apart facing each other at a 45-degree angle. And standing in between the two amps with eyes closed and the Jet Star slung over my shoulder, the sonic likeness to a Leslie was uncanny.
With the Ventilator set to Slow, a little treble horn emphasis, and a Distance setting midway between minimum and maximum, the plaintive arpeggios of Pink Floyd’s “Eclipse” came alive with a motion and breadth that was beautiful and startling. The same settings worked great for deep, funky Ernie Isley-style chord vamps too—lending a cool wobble that didn’t obscure pick attack or string muting dynamics. Faster settings benefitted less from the two-amp setup, but still made the simplest arpeggios and leads sound larger than life. Interestingly, the pedal often sounded best using the Key mode, which made the signal brighter and more defined—particularly at lower volumes.
If there’s any one mode in which the Ventilator sounds less than completely natural in a room, it’s when the Distance knob is set to zero. At these levels the Ventilator gains intensity, but loses some of the sense of dimension that is its greatest strength in a live setting. In a recording environment, however—especially one with a dense mix—the more intense pulses from the close mic’d emulation can be a huge asset, particularly if the Ventilator’s stereo output is hard panned on a mixing desk.
At nearly 500 bones on the street, the Ventilator is not cheap. Those who rarely use rotary speaker sounds may be hard pressed to justify the expense, no matter how incredible the Ventilator sounds. But if you tend to use phase or chorus effects with any regularity, the Ventilator sounds as organic as anything short of a real Leslie. And if you’re a studio hound or a session player who loves to keep a real knock-’em-dead doozy in your bag of tricks, the Ventilator can totally transform a song or composition.
It doesn’t take two amps to get a gorgeous and very real rotary cabinet sound out of the Ventilator. But if you have two amps at your disposal, it’s the best way to maximize the pedal’s potential—especially for slow, underwater, Gilmourish textures. Regardless of how many amps you use, the Ventilator can enliven the simplest song or guitar part on stage or in the studio. The pedal’s super-solid construction suggests it can survive regular use in either environment. Given that, and the fact that the Ventilator weighs about 145 pounds less than a Leslie 122, this rotary cabinet simulator could be worth its weight in gold to any modulation-happy guitar slinger.
you thirst for the unmistakable sounds of a Leslie, but haven’t the space to keep one or the dough to acquire and maintain it.
your limited use of this modulation effect won’t justify the expense.
Street $499 - Neo Instruments - neo-instruments.de