How The Groove Was Won -- Mr. Hammond invents an organ
Laurens Hammond, inventor of the eponymous organ, had built his
business on making electrical clocks -- the first Hammond organs indeed have
serial number plates from "The Hammond Clock Company". The central
part in those clocks was an electrical motor synchronised to the AC
grid's frequency. This motor would drive Hammond's baby.
Hammmond started in 1933, taking an old piano's action and
hooking various things to it. The patent for the Model A, the first
Hammond organ, was then filed on January 19, 1934. The Hammond became
an immediate success, even though, around 1938, the company was
forbidden by the FTC to claim that a Hammond could accurately
imitate a pipe organ.
The Miracle Of Overengineering -- how the Hammond works
Said synchronous motor drives, through a geartrain, a shaft
with 91 metal tonewheels, each with a sinusoidally-shaped
periphery. Moving past solenoid pickups, the generator thus
delivers 91 different sinus tones. The Hammond's pitch varies with the
DC grid's frequency, and early-model Hammonds require an elaborate
starting procedure involving a special starter motor to get the motor
to sync.
For electromagnetic shielding, the generator is mounted in a
metal casing subdivided in chambers with two tonewheels inside each
chamber.
On the underside of each key of the organ's manuals and pedals,
there are contacts (nine for manual keys, two for pedal keys) facing
so-called bus bars (i.e., nine resp. two rails running the length of
the manual/pedalboard). Pressing down a manual key thus closes nine
circuits connecting nine tonewheel pickups to the amplifier via the
global volume pedal and nine drawbars -- sliders with nine
positions (0-8) that regulate the volume of that particular tone. That
way, you can mix a tone freely from nine components. (Same goes for
the pedals, but with just two drawbars.)
A set of manual drawbars, designated by pipe lengths in feet as
in old organ tradition, and with their respective notes when hitting
the middle C:
- 16' -- suboctave (c), brown
- 5-1/3' -- fifth over suboctave (g), brown
- 8' -- basis tone, the one you are actually playing (c'),
white
- 4' -- superoctave (c''), white
- 2-2/3' -- fifth over superoctave (g''), black
- 2' -- 2nd superoctave (c'''), white
- 1-3/5' -- tierce over 2nd superoctave (e'''), black
- 1-1/3' -- fifth over 2nd superoctave (g'''), black
- 1' -- 3rd superoctave (c''''), white
There are three groups: 16' and 5-1/3'; 8', 4', 2-2/3', and 2';
1-3/5', 1-1/3', and 1'. As the numbers on the drawbars go from 0 (off)
to 8 (full blast), you can note down a registration by jotting down
the numbers for thre three groups. A typical Hammond registration
looks like "54 6312 778".
Both 61-key manuals, the lower, labeled "GREAT" and the upper,
labeled "SWELL", feature a full set of 9 drawbars. (The Name "SWELL"
is just tradition. The expression pedal regulates the entire organ's
volume.) Between the lower and upper drawbar sets, there are the two
pedal drawbars, 16' and 8', for the 25-key (concert models: 32-key)
pedalboard, which makes for a bewildering total of 20
drawbars. Side note: This is nothing. Recent Wersi models
come with up to 46 drawbars. This is because Wersi use drawbars in
the role of faders for the internal mixer, and the biggest Wersi
organs come with three manuals.
There is also a strange feature called percussion. When percussion
is enabled, pressing a key generates not only the regular drawbar
sounds, but also a 'ping' that sounds, well, percussive and decays
within a fraction of a second. The 'ping' is either 4' or 2-2/3' in
pitch (refered to as 2nd resp. 3rd harmonic percussion), and there is
a soft/normal percussion volume as well as a slow/fast percussion
decay switch.
Percussion is single-triggered, that is, a key's percussion tone
will only sound when all other keys have been completely released
beforehand. A percussion run requires a very clean staccato
technique.
Ah, the elusive scanner vibrato. This is the real rocket science
about the Hammond. The signal is fed into a delay line with eight
tapping points. A rotating air-dielectric capacitor switch, the
scanner, shifts the actual tapping point back and forth along the
line, so the output signal, as tapped from the line, periodically
shifts in pitch. The rotor is driven by the generator shaft,
incidentally.
Vibrato is generated by using that signal; chorus is generated by
mixing this 'wet' signal with the 'dry' signal from the generator. The
scanner vibrato acts as a sweeping filter, by the way,
which gives a very slight phaser effect. Vibrato and chorus are
controlled by an on/off switch and a six-way switch with settings V1,
V2, V3, C1, C2, and C3.
Usually, there is an internal tube preamp as well as internal
speakers in the Hammond. There is also an (usually) 11-pin Leslie
connector to hook up a Leslie. (Go to the Leslie node; it's
good.)
Assembling a sound
A Hammond registration is determined by the following adjustments:
- 9 upper manual drawbars (0-8)
- 9 lower manual drawbars (0-8)
- 2 pedal drawbars (0-8)
- Percussion (off/2nd/3rd)
- Percussion (norm/soft)
- Percussion (slow/fast)
- Vibrato/chorus (off/V1/V2/V3/C1/C2/C3)
This makes for an astonishing 1.02e21 of different sounds from a
purely mathematical perspective. If you count in the Leslie
Chorale/Off/Tremolo setting and the internal/external speakers
Main/Echo/Ensemble setting, you even get 9.19e21 sounds.
Well, reality is a bit different. Old-style organ jocks might tell
you something about flutes, reeds, strings and diapasons when
it comes to Hammond registration, but it's really only a mix of
sinusoidal waves, and all sounds fall into a few large groups.
Besides, no matter how much the original Hammond Organ Manual waxes on
about trumpet and xylophone sounds, you won't care about ca.-1940
registrations to imitate organ registers. This instrument has its own
sound, you'll be looking for jazz, rock, soul, blues, gospel
sounds etc. etc., and you'll end up adjusting drawbars all the time
anyway. No point in setting up and remembering something like 00 6876
540.
The basic Hammond registration is 88 8800 000. That,
without any frills (i.e. percussion, V/C and Leslie all off), is the
classic Green Onions sound, just a basic tone without fancy
harmonics. (It also makes a great Deep Purple sound with heavy
solid-state overdrive.) To smooth it out, maybe make it 68 8600
000 -- that, with vibrato 1 and percussion to taste, is the sound of
A Whiter Shade Of Pale. To make a clearer sound, try 80 8800 000 or
80 8000 000; both settings do away with the 5-1/3' fifth; to make it
even softer, go for 00 8800 000. 88 0000 000 is a low rumble.
These are the basics, and you can add white drawbars to add more
brilliance. One usually starts at the top, with that high 1' whistle,
so you get something like 88 0000 08, which gives you a neat trick
with percussion (see below). To pack on more, go for something like
80 8804 008 or 88 8808 008 (full white bars).
Those black drawbars add slight dissonance and bite to the sound,
especially 1-3/5', which is the only tierce drawbar. The 1-3/5' and
1-1/3' are usually pulled as a pair to put on some dirt on top, the
2-2/3' does the same for the middle. To get Uriah Heep sounds, try
settings like 88 8868 446 with moderate to heavy tube overdrive.
Try other stuff, too, such as 80 0008 880 or the 'even bar'
setting, 80 8080 808. Oh, and of course there's the full organ,
flat-out 88 8888 888. Add tube overdrive and you get Gimme Some
Lovin'.
Jazz organ makes heavy use of vibrato and chorus, usually plain V/C
3, with fast Leslie. Rock organ usually has slow vibrato (V1), if any,
has the Leslie going slow and changing speed for effects and
articulation (classic: Steppenwolf's Born To Be Wild, which has a
Leslie with the amp wired straight to the bass driver, and the drum
spinning up and down all the time). Blues organ is somewhere in
between. Fast vibrato (V1 or V2) without chorus tends to sound
awkward, somewhat like a home organ, but can fit some songs, such as
The Animals' House of the Rising Sun.
Percussion and triggering tricks
As mentioned above, the percussion is triggered by either the 1'
(as usual) or the 1-1/3' (on the spinet models) contact. This means
that, with percussion active, that drawbar is muted, which means you
can unmute it by switching off the percussion.
In typical organ jazz sets, you'll play a setting like 88 000 008
with full vibrato/chorus, fast Leslie and percussion in the A part.
Switch off the percussion for the B part and the 1' falls in at full
volume.
Percussion is important for jazzy solo lines, but remember it's
single-triggered, so play staccato or it won't sound good.
Percussion normally isn't the thing for chords, with some exceptions:
One is, of course, Purple's Child in Time; the other
is standard jazz organ fare: Loud percussion is neat to add play in
arpeggios with a mellow sound such as 80 0000 000. Great for comping
ballads.
Keyclick
With nine individual contacts under each and every manual key,
pressing a key causes the nine drawbar registers to come on
sequentially, not all at once. This causes a characteristic 'smack' or
'click'. Its character depends on the key velocity and it has been
said that it's different for every organist.
Keyclick is a must especially for jazz organists.
Leakage
The strong magnetic fields in the tone generator's chambers
interact with each other and with the pickups. This causes signals to
'leak' out, 'singing' or even 'grunting' into the wrong pickups,
making the sound 'dirtier'. Anti-leakage filters are built into most
Hammonds, but due to the tolerancies in making them, their
success varies from organ to organ. No Hammond sounds the same.
Overdrive
Overdrive can come from the organ's internal preamp or from the
Leslie's amplifier. When pulling out more and more drawbars, a
well-adjusted Hammond goes into overdrive somewhere short before the
full setting so you can adjust the drive with the drawbars.
Hot Like 91 Wheels -- dates and models
- 1935 (June) First Hammond (Model A) released
- 1939 Novachord released, a tube
polysynth; arguably cool, but not very successful
- 1955 B-3 released (the Hammond), M-3 released (its
spinet brother)
- 1959 A-100 released
- 1961 L-100 and M-100 released
- 1965 H-100 released
- 1974-1976 All 'real' Hammonds go out of production
- 2002 Hammond Suzuki introduce the New
B3, a fully electronic instrument that is identical to the B3 in
looks and sounds, as even experts admit.
Hammond Suzuki products available today (May 2002):
- Leslie 122XB
- Leslie 21
- New B3
- XB-1 one-manual budget stage organ ('drawbar keyboard')
- XB-3 organ
- XE-1 Compact Hammond organ/entertainer keyboard with optional
XLK-1 lower manual, XPK-100 pedalboard and polished-wood STE-1 stand
- XE-200 spinet organ/entertainment system
- XH-200 console home organ
- XH-200SP spinet/console home organ
- XK-2 one-manual stage organ
- XM-1 rackmount sound module with optional XMC-1 drawbar controller
- XT-100 spinet organ/entertainment system
All Hammond products are now sample-based. None of them have got
tonewheels.