I am reprinting this useful info that i found on the internet at this interesting link on a site called "Inside the Fender Vibratone" It is a great read! http://www.nmia.com/~vrbass/vibratone/
"The Fender Vibratone is a variant of the Leslie Model 16 and 18 speaker cabinets. (CBS bought both Fender and Leslie in the mid-1960s.) Like other Leslies, the Vibratone contains a rotating drum mounted in front of a 4-ohm speaker (a 10" in the case of the Vibratone and Leslie 16; a 12" in the case of the Leslie 18). This drum is hollow, with a curved chute which acts as a deflector for the sound, directing the signal around the room and causing interesting and uniquely characteristic phasing effects. This is the basic principle of the Leslie cabinet, and the Vibratone is just a type of Leslie. They all produce phasing effects by firing their speakers into rotating diffusers which bounce the sound off of everything around them.
Like most Leslies, the Vibratone has two speeds, dubbed chorale (slow) and tremelo (fast). The chorale speed, also called chorus, is about 40 revolutions per minute, while the tremelo is about 340 rpm. The chorale effect is a slow, shimmering kind of sound on which the familiar chorus pedal is based. It can be very subtle or can wash over the whole tonality of the instrument, depending upon how it's miked. You may or may not even notice it unless you're listening for it. On the other hand, the tremelo effect is a fast, warbling effect that is immediately recognizable and unmistakably organ-like, though again miking will make it more or less prominent.
But there are some differences that make the Vibratone a unique variety of Leslie. Unlike most Leslie speakers, these cabinets are unamplified, acting as an extension speaker for an instrument amplifier. And unlike other Leslie cabinets, they take 1/4" phono plug inputs, like a guitar speaker cabinet. And they're built like guitar cabinets, with a Tolex covering, sparkly grillcloth, and handles, while the classic Leslie for organs is an elegant piece of hardwood furniture. Most likely, the intent was to give players of "combo" organs (e.g. Vox, Farfisa) access to the Leslie sound. They already had amps, so all they needed was the cabinet. But the chart successes of several songs with Leslie guitar sounds in 1965 and 1966 may have alerted them to the larger market for the cabinets."
This one we have is in very good condition, given that these were often treated pretty harshly when used on the job, they didn't always fit as nicely in the boot of a car for example. Also, it has all the connectors required to run it, it works nicely and sounds amazing. if you have a studio, you may not know it yet, but you need this fella!