Hammond SK Pro-73 73-Key Portable Keyboard/Organ - Manual (Page 86)

*#1 SK PRO/SK PRO-73 Owner’s Manual
86
VIBRATO & CHORUS
SHORTCUT: Press and Hold the VIBRATO and CHORUS [MODE], [UPPER] or [LOWER] buttons.
Th is Page allows you to adjust the Vibrato & Chorus of the Tone Wheel Organs,
Vibrato for the Transistor Organs, and Tremulant for the Pipe Organ.
TONE WHEEL ORGAN
TYPE
Settings: See below
Th is allows you to select the Vibrato Delay Line type.
’55-57 ........Metal Box (1955 - 1957).
’57-59 ........Big Silver Box (1957 - 1959).
’59+ ............Small Silver Box (1959 or later).
RATE
Setting Range: 5.78 ~ 7.90 Hz (349 ~ 475 rpm)
Th is allows you to adjust the rate of the Vibrato & Chorus.
MIX
Setting Range: D64 ~ Even ~ 63V
Th is allows you to adjust the intensity of the Chorus (C1 to C3).
“D” = direct or dry sound. “V” = Vibrato sound.
PEDAL
PEDAL
Settings: Off , On
Th is allows you to select whether the Vibrato & Chorus aff ects the PEDAL Part when
the Vibrato & Chorus [LOWER] button is “ON.”
TRANSISTOR ORGAN
RATE
Setting Range: 0 ~ 127
Th is allows you to adjust the rate of the Vibrato.
PIPE ORGAN
TREMULANT RATE
Setting Range: 0 ~ 127
Th is allows you to adjust the rate of the Tremulant.
PEDAL
On the B-3/C-3/A-100, the Vibrato and Chorus
affects the Pedal tones in addition to the Lower
Manual Drawbar tones. Also, starting with the
B-2/C-2, vintage Hammonds had
Selective
Vibrato , meaning that Vibrato could be had on
Upper and Lower Manuals/Pedal independently
(on previous models the Vibrato and Chorus
aff ected the entire organ). These are replicated on
the SK PRO.
VIBRATO TYPE
Hammond tone-wheel organs with Vibrato &
Chorus were manufactured from 1949 through
1975. During that time, several diff erent types of
vibrato circuits were employed, particularly line
boxes of diff erent constructions. The Vibrato TYPE
feature replicates the effect of different types of
Vibrato delay lines.
ORGAN - continued
VIBRATO (TRANSISTOR ORGAN)
On an electronic organ, Vibrato is accomplished
by modulating the frequency of the master
oscillator(s.) This eff ect is replicated on the SK PRO.
TREMULANT
On a pipe organ, a Tremulant varies the air
pressure the air pressure to the pipes periodically,
producing a vibrato or tremolo eff ect. On the SK
PRO, Tremulant can be applied to the Pipe Voices.
Scanner
Amplifier
Amplifier
Sections Of Vibrato DelayLine
VIBRATO & CHORUS
T h e i l l u s t r a t i o n a b o ve s h o w s t h e v i b r a t o
equipment of a tone-wheel Hammond Organ such
as a B-3/C-3/A-100.
On a tone-wheel Hammond Organ equipped with
Vibrato & Chorus, the vibrato circuitry consists of
a series of plural coils or low-pass filter sections
called a “delay line” or “line box” and a motor-
driven “scanner” which scans the delay line and
progressively retards the phase, creating the
Vibrato eff ect.
MIX
“Vibrato Chorus,” is obtained when the vibrato
output signal is mixed with a portion of signal
without vibrato. This creates a “shimmering”
eff ect much used by jazz, blues and rock organists.
This Parameter allows you to adjust the balance
between the Vibrato and non-Vibrato signals to
create the type of Chorus eff ect you want.