The Hammond organ is an electric instrument created by Laurens Hammond and John M. Hanert. It was first made in 1935. Many models have been produced, and most use sliding drawbars to change sounds. Before 1975, sound was made by spinning a metal wheel near an electromagnetic pickup, and the electrical signal was then amplified through a speaker cabinet. The Hammond organ is often used with a Leslie speaker.

About two million Hammond organs have been made. The instrument was first sold by the Hammond Organ Company to churches as a less expensive option compared to wind-powered pipe organs or pianos. It quickly became popular among professional jazz musicians in small groups called organ trios. Club owners found that these trios were cheaper than hiring a large band. Jimmy Smith’s use of the Hammond B-3, which includes a special harmonic percussion feature, influenced many musicians. This organ became widely used in the 1960s and 1970s in styles such as rhythm and blues, rock (especially progressive rock), and reggae.

In the 1970s, the Hammond Organ Company stopped using tonewheels and switched to integrated circuits. These new models were less popular, and the company closed in 1985. The Hammond name was later bought by the Suzuki Musical Instrument Corporation, which made digital versions of the most popular tonewheel organs. This led to the creation of the "New B-3" in 2002, a digital copy of the original B-3 organ. Hammond-Suzuki continues to make a variety of organs for both professional musicians and churches. Companies like Korg, Roland, and Clavia have also made lighter, portable versions of tonewheel organs, called clonewheel organs. The sound of a tonewheel Hammond organ can now be recreated using modern software audio tools.

Features

The Hammond organ has features not usually found on a piano or synthesizer. Some parts are similar to a pipe organ, but others are only found on the Hammond organ.

Most Hammond organs have two 61-note (five-octave) keyboards called manuals. Like pipe organ keyboards, the two manuals are placed on two levels close to each other. Each manual is arranged like a piano keyboard, but pressing a key on a Hammond makes the sound play continuously until the key is released. On a piano, the sound gets softer over time. The volume on a Hammond does not change based on how hard or soft a key is pressed, so players use a pedal (called a "swell" or "expression" pedal) to control the overall volume. The keys on each manual have a lightweight action, making it easier to play fast notes than on a piano. Unlike piano or pipe organ keys, Hammond keys have a flat-front shape, often called "waterfall" style. Early models had sharp edges, but later models, like the B-2, had rounded edges because they were cheaper to make. The M series of spinets also had waterfall keys, which made them useful for replacing parts on B-3s and C-3s. Later spinet models had "diving board" style keys, similar to those on church organs. Modern Hammond-Suzuki models use waterfall keys.

Hammond console organs include a wooden pedalboard played with the feet for bass notes. Most console pedalboards have 25 notes, starting with a low C and ending with a middle C two octaves higher. Hammond used a 25-note pedalboard because he found that the top seven notes on traditional 32-note church pedalboards were rarely used. Some Hammond Concert models, like the E, RT-2, RT-3, RT-3, and D-100, had 32-note pedalboards that reached up to the G above middle C. These models also had a separate solo pedal system with its own volume control and other features. Spinet models had smaller pedalboards with 12 or 13 notes.

Hammond manuals and pedalboards were originally made with solid palladium alloy wire to ensure strong electrical connections when keys were pressed. This design was later replaced with transistor technology. This means tonewheel Hammond organs contain between 3.2 and 8.4 grams of palladium, depending on the model.

The sound of a Hammond organ is changed using drawbars. A drawbar is a metal slider that controls the volume of a specific sound part, like a knob on an audio mixing board. Pulling a drawbar out increases its volume, and pushing it all the way in reduces the volume to zero.

The drawbar labels come from the pipe organ system, where the length of a pipe affects the pitch. Most Hammond organs have nine drawbars per manual. The "8′" drawbar produces the main note, the "16′" drawbar is an octave below, and the "4′", "2′", and "1′" drawbars are one, two, and three octaves above, respectively. Other drawbars create harmonics and subharmonics. Mixing these drawbars can create complex sounds, making the Hammond organ a type of additive synthesis.

Hammond organs made after 1969 have the length of each drawbar engraved on its end. Some drawbar settings are famous and linked to certain musicians. A popular setting is 888000000, which is known as the "classic" Jimmy Smith sound.

Many Hammond models also have presets, which are pre-set drawbar combinations activated by pressing a button. Console organs have one octave of reverse-colored keys (naturals are black, sharps and flats are white) to the left of each manual. The far-left key (C) deactivates all presets, and the two right-most keys (B and B♭) activate specific drawbar settings. Other preset keys have preselected settings built into the organ.

Hammond organs include a built-in vibrato effect, which slightly changes the pitch while a note is played, and a chorus effect, where a note’s sound is combined with another sound at a slightly different pitch. The most well-known system has six settings (V1, V2, V3, C1, C2, C3) selected with a rotary switch. Vibrato and chorus can be used independently on each manual.

The B-3 and C-3 models introduced "Harmonic Percussion," which mimics the sounds of a harp, xylophone, and marimba. When activated, this feature plays a short, decaying second- or third-harmonic overtone when a key is pressed. The volume of this effect can be set to normal or soft. Harmonic Percussion only triggers after all notes are released, so it works best on the first note or chord of a legato passage.

Before a Hammond organ can make sound, the motor that turns the tonewheels must reach full speed. Most models require two switches: the "Start" switch turns on a starter motor for about 12 seconds, and the "Run" switch is then turned on for about four seconds. After this, the organ is ready to play. Some models, like the H-100, E-series, L-100, and T-100, had self-starting motors that only needed a single "On" switch. A pitch bend effect can be created by turning the "Run" switch off and on again, briefly slowing the motor to lower the pitch. The New B3 model includes similar switches, though it is a digital instrument.

History

The Hammond organ's technology came from the Telharmonium, an instrument invented in 1897 by Thaddeus Cahill. The Telharmonium used spinning electric generators to create tones that could be sent through wires. The instrument was very large, requiring several train cars to move it, because the generators needed to be big enough to produce strong electrical signals. The Hammond organ solved this issue by using an amplifier.

Laurens Hammond graduated from Cornell University with a degree in mechanical engineering in 1916. By the early 1920s, he had designed a spring-powered clock that helped him start his own business, the Hammond Clock Company, in 1928. In addition to clocks, his early inventions included 3D glasses and an automatic bridge table shuffler. However, as the Great Depression continued into the 1930s, sales of the bridge table dropped, and he decided to find another product to sell. Inspired by the sounds of gears in his electric clocks, Hammond created the tonewheel, or "phonic wheel." He used parts from a second-hand piano he bought for $15 and combined them with a tonewheel generator, similar to the Telharmonium but smaller and more compact. Since he was not a musician, he asked W. L. Lahey, the company’s assistant treasurer and a trained organist, to help create the desired organ sound. To save money, Hammond made a pedalboard with only 25 notes, instead of the usual 32 on church organs. This became a widely accepted standard.

On April 24, 1934, Hammond filed a patent for an "electrical musical instrument." Hanert, the co-inventor, personally delivered the patent to the patent office, explaining that production could begin immediately and would help create jobs in Chicago. The invention was shown to the public in April 1935, and the first model, the Model A, was available in June of that year. Over 1,750 churches bought a Hammond organ in the first three years of production. By the end of the 1930s, more than 200 instruments were made each month. By 1966, about 50,000 churches had installed a Hammond organ. Although the organ later became popular with professional musicians, the original company did not aim to sell it to that market, believing there would not be enough profit.

In 1936, the Federal Trade Commission (FTC) accused the Hammond Company of making "false and misleading" claims in its advertisements, such as saying the Hammond could produce "the entire range of tone coloring of a pipe organ." This led to long legal hearings, including tests where a Hammond organ costing about $2,600 was compared to a $75,000 Skinner pipe organ in the University of Chicago’s Rockefeller Chapel. Musicians and others tried to tell the difference between the two instruments. Hammond’s lawyers argued that listeners were often wrong, while FTC witnesses claimed Hammond employees had made the Skinner organ sound more like the Hammond. In 1938, the FTC ordered Hammond to stop making certain claims, such as saying its instrument was equal to a $10,000 pipe organ. Hammond claimed the hearings proved his company’s belief that the organ made "real," "fine," and "beautiful" music, even though these phrases were not included in the "cease and desist" order. He also said the publicity from the hearings helped sell enough organs to cover the costs.

The Hammond Organ Company produced about two million instruments in its lifetime, which are considered "probably the most successful electronic organs ever made." A key factor in its success was the use of dealerships and a sense of community. Many organ dealers opened businesses in the United States, and a newsletter called The Hammond Times was sent to subscribers every two months. Advertisements often showed families gathered around the instrument, with a child playing it, to show the organ as a central part of home life and to encourage children to learn music.

Hammond organs made by the original company can be divided into two main groups:

• Console organs have two 61-note manuals and a pedalboard with at least two octaves. Most consoles do not have built-in amplifiers or speakers, so an external amplifier and speaker cabinet are needed.
• Spinet organs have two 44-note manuals and one octave of pedals, plus an internal amplifier and speakers.

The first model produced in June 1935 was the Model A. It included many features that became standard on all console Hammonds, such as two 61-key manuals, a 25-key pedalboard, an expression pedal, 12 reverse-color preset keys, and one for the pedals.

To improve the Hammond’s sound, the Model BC was introduced in December 1936. It added a chorus generator, which used a second tonewheel system to create slightly sharp or flat tones, making the sound richer. The cabinet was made deeper to fit this. Production of the old Model A cases stopped, but the older model was still sold as the AB until October 1938. A Model BA from 1938 can be seen and heard at the Musical Museum in Brentford, England.

Criticism that the Hammond looked more like a home instrument than a church organ led to the introduction of the Model C in September 1939. It had the same internal parts as the AB or BC but added "modesty panels" to cover female organists’ legs when playing in skirts. The Model C did not include the chorus generator, but the cabinet had space for it. The Model D was a Model C with the chorus generator already installed. The vibrato system was developed in the early 1940s and added to production after World War II. Models available included the BV and CV (vibrato only) and the BCV and DV (vibrato and chorus).

The B-2 and C-2 models, introduced in 1949, allowed vibrato to be turned on or off for each manual separately. In 1954, the B-3 and C-3 models were introduced with

Speakers

The approved loudspeaker enclosure for a console organ was the Hammond Tone Cabinet, which included an external amplifier and speaker. This cabinet received a balanced mono signal and AC power directly from the organ through a six-pin cable. Spinet organs had built-in amplifiers and speakers.

The tone cabinet was the original way to add reverberation to a Hammond organ. The first models made were the 20-watt A-20 and 40-watt A-40. The A-20 was designed for churches and small halls and had doors in front of the speaker that could be closed when the organ was not being used. The D-20, introduced in 1937, allowed sound to escape only through a slotted opening on one side and a gap at the top. The PR series, released in 1959, became very popular. The 40-watt PR40 weighed 126 pounds (57 kg) and was 37.5 inches (950 mm) tall. It responded well to bass pedal inputs.

Many musicians prefer to use a Hammond organ with a cabinet that has a rotating speaker, later known as a Leslie speaker, named after its inventor, Donald J. Leslie. A typical Leslie system combines a speaker and amplifier. It produces sound through a rotating horn above a stationary treble speaker and a rotating baffle below a stationary bass speaker. This creates a unique sound due to the changing pitch caused by the movement of the sound sources, an effect called the Doppler effect.

The Leslie speaker was designed to copy the complex tones and shifting sounds of a large pipe organ. The effect depends on the speed of the rotating parts, which can be set to fast (tremolo) or slow (chorale) using a console switch or pedal. The most popular models were the 122, which used a balanced signal for console organs, and the 147, which used an unbalanced signal and could connect to spinet organs with an adapter. The Pro-Line series, made for portable use with solid-state amplifiers, became popular in the 1970s.

Leslie first tried to sell his invention to Hammond, but Laurens Hammond refused to buy it. Hammond changed their connectors to prevent Leslie speakers from working, but Leslie found a way to fix the problem. Some Hammond employees thought Hammond was being unfair to Leslie, but Leslie later said the situation helped promote his speakers.

In 1965, the Leslie company was sold to CBS. The next year, Hammond officially supported the Leslie speaker. The T-200 spinet, released in 1968, was the first Hammond organ with a built-in Leslie speaker. Hammond bought Leslie in 1980. In 1992, Hammond-Suzuki acquired the rights to Leslie. Today, the company offers original Leslie speakers and announced in 2013 that it would produce a standalone Leslie simulator in a stomp box.

Tone generation

Hammond organs are often grouped with electronic organs, but most are actually electric or electromechanical. This is because their sound is created by moving parts, not electronic oscillators.

The main sound of a Hammond organ comes from a tonewheel. Each tonewheel spins in front of an electromagnetic pickup. As the tonewheel moves, it changes the magnetic field, creating a small electrical current at a specific frequency. This current is similar to a sine wave. When a key is pressed, it connects nine electrical switches linked to the drawbars. The position of the drawbars and the switches chosen by the key determine which tonewheels produce sound. Each tonewheel is connected to a motor through gears, ensuring all notes stay in a consistent pitch relationship.

The combined sound from all pressed keys and pedals is sent to the vibrato system, which uses a rotating metal scanner. As the scanner moves, it slightly changes the pitch of the overall sound.

Next, the sound travels to the main amplifier and then to the speakers.

Hammond organs make compromises in tuning. Instead of using exact harmonic multiples as in equal temperament, they use the closest available frequencies from the tonewheels. The only guaranteed frequency is concert A at 440 Hz.

Crosstalk, or "leakage," happens when magnetic pickups pick up signals from tonewheels not selected by the organist. Hammond initially saw this as a problem and added resistor–capacitor filters in 1963 to reduce crosstalk and 50–60 Hz hum. However, the sound of crosstalk is now considered a key part of the Hammond organ’s unique tone, and modern digital copies often mimic it.

Some Hammond organs make a short pop or click when a key is pressed. This was once seen as a flaw, and Hammond tried to reduce it with filters. However, many musicians preferred the sharp, percussive sound, and it became a defining feature. Alan Young, a Hammond engineer, noted that performers liked the clear attack of the sound.

Because Hammond organ tones are mechanically generated, different models were made for the US and Europe. US models run on 110 volts at 60 hertz, while European models use 240 volts at 50 hertz. These models have different gears and motors, spinning at 1,200 RPM and 1,500 RPM, respectively. Adapters are available to allow Hammond organs to work in different regions, and they are used by bands that tour internationally.

Clones and emulation devices

The original Hammond organ was not made to be moved often. A Hammond B-3 organ, along with its bench and pedalboard, weighs 425 pounds (193 kg). When combined with a Leslie speaker, the total weight makes the instrument hard to carry between places. This led to a need for a lighter and easier-to-use instrument that could still produce the same sound. Electronic and digital keyboards that copy the sound of the Hammond are called "clonewheel organs."

The first efforts to copy the Hammond electronically began in the 1970s. These included models like the Roland VK-1 and VK-9, the Yamaha YC45D, and the Crumar Organizer. The Korg CX-3 (single manual) and BX-3 (dual manual) were the first lightweight organs to create a sound similar to the original Hammond. Gordon Reid from Sound on Sound said the CX-3 "came close to matching the deep and emotional sound of a vintage Hammond," especially when played through a Leslie speaker.

In 1997, the Roland VK-7 tried to copy the Hammond’s sound using digital signal processing. An improved version, the VK-8, released in 2002, also copied sounds from other old keyboards and included a connection for a Leslie speaker.

Clavia introduced the Nord Electro in 2001. This model used buttons to copy the physical movement of adjusting a drawbar, with an LED display showing the current setting. Clavia later released updated versions of the Electro and created the Nord Stage using the same technology. The Nord C2D was Clavia’s first organ with real drawbars.

Diversi, started in 2003 by Tom Tuson, a former Hammond-Suzuki sales representative, focused on making Hammond copies. The company received support from musician Joey DeFrancesco.

The Hammond organ has also been copied in software. One well-known example is the Native Instruments B4 series, which has been praised for its detailed design and features. Emagic (now part of Apple) also made a software copy called the EVB3. This software allowed a Hammond organ module with all the controls and features of the original to be included in the Logic Pro audio production program.

Notable players

Early customers of the Hammond organ included Albert Schweitzer, Henry Ford, Eleanor Roosevelt, and George Gershwin. At first, some classical musicians did not like the Hammond because the sound of two notes an octave apart was perfectly matched, unlike the slightly different sounds on a pipe organ. However, jazz musicians gradually began to use the Hammond. Ethel Smith, known as the "first lady of the Hammond organ," was one of the first to perform on it. Fats Waller and Count Basie also started using the Hammond. Organist John Medeski said the Hammond became "the poor man's big band," which made it easier and cheaper to book organ trios.

Jimmy Smith began playing the Hammond regularly in the 1950s, especially during his recordings for the BlueNote label between 1956 and 1963. He played all the bass parts himself using the pedals, often combining a walking bassline with rhythmic chords on the left hand. His trio format, which included the Hammond, guitar, and drums, became famous after a performance at the Newport Jazz Festival in 1957. Medeski said musicians were inspired by Jimmy Smith's recordings. "Brother" Jack McDuff switched from piano to Hammond in the 1950s and performed regularly in the 1960s and 1970s. Keith Emerson tried to copy McDuff's sound in his arrangement of "Rock Candy." Emerson also admired Billy Preston's work, especially the 1965 piece "Billy's Bag." He avoided using the Leslie speaker, thinking it was Preston's style, and instead combined a European musical approach, classical music, and rock.

Booker T. Jones is considered a key figure in connecting rhythm and blues to rock. British organist James Taylor said the Hammond became popular in the UK when artists like Booker T. & the M.G.'s and Stax Records musicians performed in London. Matthew Fisher first heard the Hammond in 1966 when he listened to Ian McLagan of the Small Faces play it. After hearing him, Fisher decided to buy a Hammond. He played the Hammond on Procol Harum's "A Whiter Shade of Pale," which became a top hit in the UK in 1967. Steve Winwood started his career playing guitar and piano with the Spencer Davis Group but switched to the Hammond when he used it to record "Gimme Some Lovin'."

Gregg Allman became interested in the Hammond after hearing Jimmy Smith's music. His brother, Duane, asked him to play the Hammond when forming the Allman Brothers Band. Allman received a new B-3 and Leslie 122RV when he joined the band. He remembered the instrument was hard to move, especially on stairs, and required the whole band's help. Author Frank Moriarty said Allman's Hammond playing was an important part of the band's sound.

Deep Purple's Jon Lord was inspired to play the Hammond after hearing Jimmy Smith's "Walk on the Wild Side." He modified his Hammond to use a Marshall amplifier, creating a loud, distorted sound that became his trademark. This instrument was later used by Joey DeFrancesco. Hugh Banton, a member of Van der Graaf Generator, made many changes to his Hammond E-100, including adding effects and rewiring the motor. He described the result as "unimaginable sonic chaos."

The Hammond was important in progressive rock music. Author Edward Macan said this was because the Hammond could play both chords and lead lines, and it could produce quiet, clean sounds or loud, aggressive sounds. However, historian Paul Stump said the Hammond's popularity in progressive rock was more about how common it was in other music, like the electric guitar. Emerson first gained fame with the band the Nice, where he used an L-100 in unusual ways, such as cutting it with knives or riding it on stage. He continued to use the Hammond in Emerson, Lake and Palmer. Other notable Hammond players in progressive rock include Rod Argent of Argent, Tony Kaye and Rick Wakeman of Yes, Thijs van Leer of Focus, Ken Hensley of Uriah Heep, Richard Wright of Pink Floyd, Steve Walsh of Kansas, and Tony Banks of Genesis. Banks later said he used the Hammond because it was easier to transport than a piano.

Ska and reggae music often used the Hammond in the 1960s and 1970s. Junior Marvin started playing the Hammond after hearing Booker T. & the MGs' "Green Onions," though he found it heavy. Winston Wright was known as one of the best Hammond players in Jamaica. He used the Hammond when performing with Toots and the Maytals and on recordings with Lee "Scratch" Perry, Jimmy Cliff, and Gregory Isaacs. Tyrone Downie, best known as Bob Marley and the Wailers' keyboardist, used the Hammond on "No Woman, No Cry," recorded at the Lyceum Theatre in London for the album Live!

By the late 1970s, the Hammond was seen as old-fashioned, especially in the UK, where it was often used for pop songs in social clubs. Punk and new wave bands preferred used combo organs from the 1960s or no keyboards at all. Some groups used cheaper, portable synthesizers instead. Dave Greenfield of The Stranglers was an exception, using a Hammond during the band's early years. Andy Thompson, known for the Mellotron, said the Hammond was still used in many studios. The Hammond had a brief revival in