10.6

657Logic Pro Instruments
The Hammond B3 was manufactured between 1955 and 1974. It is the Hammond model
preferred by jazz and rock organ players, such as Fats Waller, Wild Bill Davis, Brother
Jack McDuff, Jimmy Smith, Keith Emerson, Jon Lord, Brian Auger, Steve Winwood, Joey
DeFrancesco, and Barbara Dennerlein.
In addition to the B3, there are a number of smaller Hammond instruments, known as
the spinet series (M3, M100, L100, T100). Bigger console models, many of which were
designed to suit the needs of American churches or theaters (H100, X66, X77, E100, R100,
G-100), were also manufactured.
The production of electromechanical organs ceased in 1974. Thereafter, Hammond built
fully electronic organs.
The Hammond name lives on in the Hammond-Suzuki range of electronic draw bar organs,
starting with the 2002 release of a digital B3 model that mimics the design and functions
of the classic B3 (without the weight). This model, as well as newer units, can be partnered
with real, mechanical, rotor speaker cabinets, also from the company.
The Leslie cabinet
Don Leslie developed his rotor cabinets in 1937 and began marketing them in 1940.
Laurens Hammond wasn’t keen on the concept of rotating speakers at all.
Leslie’s approach was to simulate a variety of locations in the pipes (as in pipe organs),
resulting in a new spatial perception for every note. The rotor speaker cabinets could
simulate this effect, and the sense of space that they impart is incomparable, when placed
side-by-side with any fixed speaker. The periodic undulations in sound and volume and the
vibrato caused by the Doppler effect (see below) aren’t all there is to the Leslie sound—it’s
the spatial effect, too.
The “classic” Leslie speaker design features two drivers—a treble driver with horns (only
one works; the other simply acts as a counter-weight) and a bass driver. The horns of
the treble driver and the sound baffle of the bass driver are physically rotated by electric
motors.
Because the speakers rotate toward the front of the cabinet (the listening position), then
toward the back of the cabinet, you hear a “Doppler effect”—where sounds become louder
and brighter as their position changes. To give you an idea of this effect, it is much like the
sound of a train going past if you were standing on the platform. On approach, the sound
is muffled, but then it becomes both louder and brighter as the train passes, and finally it
becomes more muffled as it moves away from you.
The rotating driver/sound baffle can be switched between two speeds—fast/Tremolo or
slow/Chorale (or stopped completely with a mechanical brake). The transition between
the two speeds, or the use of a fixed speed, produces the characteristic “Leslie” vibrato,
tremolo, and chorus effects.
The first Leslie, the model 30, had no Chorale—just tremolo and stop. The Chorale idea
(which came much later) was born of a desire to add a vibrato to the organ. Chorale, which
offers far more than a simple vibrato, was first introduced to the market with the 122/147
models. At this time, Leslie also added the “Voice of the pipe organ” label to his cabinets.
It wasn’t until 1980 that the two companies and brand names came together, six years after
the last tonewheel organ was built. Mechanical Leslie rotor cabinets are still being built
today, by the Hammond-Suzuki company.