RMI KC-II User manual

Rocky Mount instruments, Inc.
Sales Office: Macungie, Pa. 18062
Phone: [phone]
Subsidiary of Alien Orgsn Company
© 1977
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MODEL
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THE
FIRST
DIGITAL
POLYPHONIC
SYNTHESIZER

HEVBDflRD
CDMPUTER
Model KC-11 Keyboard Computer:
In 1974 musicians hearing the Keyboard Computer for the first time responded with comments like
"Astounding!" or "Can't believe it!" The Computer's ability to polyphonically generate twelve voices
simultaneously added to the excitement. The idea began to catch on. Some "big-name" artists picked it up.
Concerts, record albums, and two years later, we realized the sound of the KC was here to stay. It was
time to create KC-II. Making the Computer easier to play, we added a new Permanent Voice Memory
containing popular KC sounds of the past few years, Presets for quick changes, a few extra pedal controls
for further flexibility, and Rocker Controls with greater function description.
The RMI Keyboard Computer is: NOT a Piano . . . NOT a Synthesizer . . . NOT an Organ
The Keyboard Computer Tone Generation System has: NO Audio Oscillators . . . NO Formant
Filters . .. NO Organ Divider Circuits . . . NO Electro-Mechanical Moving Parts . . . NO Voltage Controlled
Tracking Trims or Op Amp Off-Set Trims ... NO Critical Periodic Calibrations to be Maintained.
The RMI Keyboard is truly a Musical Digital Computer:
If a sound is to be duplicated, the harmonic content of its waveform must be duplicated. Filter circuits
can extract waveforms from oscillators. However, filtering is largely guesswork, and control of many complex
waveforms is just about impossible, as anyone familiar with synthesizers will attest. A more predictable
method has arrived. Allen Organ introduced a new system in 1971 to be shared by RMI—the Musical
Digital Computer.
The principle of operation is similar to that of an artist's reproducing an enlarged picture on a billboard
employing a grid of squares to aid their accuracy. The waveform to be reproduced is analyzed on a graph.
Points where the waveform intersects the grid are assigned numbers and the numbers are stored in the
computer. Reading this group of numbers out at the frequency of a given musical pitch regenerates the
waveform. This concept provides an order of accuracy in waveshape control never before achieved. With
all waveforms reduced to a series of numbers, the ability to repeat a given sound is absolutely precise and
very quick—a feature concert and studio musicians alike will appreciate. To indefinitely expand the Com
puter's tonal range, these number series representing waveforms have been punched on standard computer
cards—hundreds are available from an ever increasing Tone Card Library for use in the Computer's Card
Reader. The most popular and useful sounds have been stored in a Permanent Memory LSI device that
can be activated manually or by Twelve Presets. Sounds from the Permanent Memory'and Card Reader
can be mixed in any combination.
Presets allow instant change of contrasting sounds:
Strings—musicians who have heard agree nothing else approaches the realism of the KC strings. Attack/
Decay and Vibrato are pedal-controlled. Even the "bowing noise" is heard.
Electric Organ—tell-tale sound of that famous electro-mechanical organ with drawbars, third harmonic
percussion and two speed revolving speakers.
Organ and Bells—Variable with foot pedals from Bells to high-pitched funky organ percussion.
Organ and Guitar—Stereo effect. Guitar can be stylized with. Pitch Bender pedal from a sliding Pedal
Steel to Rock Guitar.
Horn—mellow and rich non-imitative sound good for jazz work.
Electric Piano—warm and realistic, complete with sustain pedal.
Clav—highly characteristic.
Jazz Flute and Clav—stereo effect. Jazz Flute complete with "over-blow" transients due to "tongueing".
Alto Recorder and Harpsichord—stereo effect. Exceptionally delicate and articulate.
Bells—clanging realism due to KC's forte in complex waveforms and chorus tuning.
Pipe Organ—Diapason Chorus with four-rank Mixture.
Echo—notes repeat like tape echo, but in a different tone color one octave lower. Rate is pedal-variable.
Add Manual—instantly combines manual set-ups with presets.
Other popular set-ups: #
Calliope with Chiff, Cathedral Choir, Ring Modulator Gong, Steel Drum, Sax with Random Over-Blow
Effect, Marimba, Tubular Chimes, Assorted Pulses for Funk sound, Several Bell effects, Jaw Harp,
Bagpipe, Banjo, etc.
Processors Create Contrasting Voices in Stereo:
Twelve independent Digital Voice Processors are each capable of generating independent frequencies,
attack/decay envelopes, and waveforms. Processors can be assigned to the keyboard in one, two, or three-
to-a-key modes for multiple voice-per-key effects. Processors can be split in Stereo for contrasting effects—
example: Alto Recorder vs. Harpsichord. Groups of Processors can be assigned various pitch deviations
such as Chorus Tuning or Vibrato. Chorus Tuning is a phenomenon of acoustic instruments due to slight
"imperfections" in tuning—slight beats are heard between two notes closely in tune.
Envelope Controls Provide a Degree of Sophistication beyond Synthesizers:
Digital Envelope Generation provides a stop-motion feature freezing a note or chord while other notes or
chords can be played independently—handy for multiple keyboard performers who need a sustained chord
on one instrument while playing another. Successive chords can be cross-faded or latched at any point in
the fade. Percussion, Sustain, or Variable Attack/Decay can be assigned to different groups of Processors
for multiple envelope effects in Stereo. Scaled Attack/Decay is an effect musicians have grown to expect
from acoustic instruments—higher pitched notes are faster and lower notes are slower due to physical size
and resonance of the instrument (example: Tuba vs. Piccolo). The KC offers two different curves of Scaled
Attack, one Scaled Decay curve, a Pedal-Variable Attack/Decay, or an abrupt Staccato Attack/Decay for
funky playing. Certain envelopes can be Delayed for Echo effects.
Pedal Assembly Provides Expression and Flexibility:
When both hands are busy at a Polyphonic keyboard, Pedal Controls become an absolutely necessary part
of expression; therefore, RMI includes its pedal assembly at no extra charge. Volume Pedals control the
left and right Stereo Channels independently. Length of Percussion, Sustain, and Variable Attack/Decay
Modes are pedal-controlled. Pitch-Bending a Perfect Fourth sharp or flat is controlled by a spring-loaded
pedal to assure return to standard pitch. Sustain Latch, Staccato Mode, Percussion, and Sustain are
footswitch controlled. Vibrato intensity, a critical factor in music, varies from none to a shaking synthesizer
effect with the Vibrato Pedal.
RMI is famous for its Rugged Construction and Quality:
Feel it. Lift it. Rap on the case—tough! Check out our legs—sturdy, but easy to set up. Open the lid
and look inside—notice the neatness? Feel the natural wood key action with individually-adjustable
tension, travel, and point-of-contact—we build it ourselves. Tilt the Rocker Controls—notice the feel?
Rocky Mount Instruments are built to last.
Package:
High-impact molded case withstands rough handling on the road. Keyboard and controls have locking
cover. Case: height 9-3/4"—width 44"—depth 24-1/2"—weight 99 lbs. Four heavy chromed steel legs
unfold adding 26-3/4" to total height.

MODEL
KEVBDflRD
hC-H CDMPJTER
FROM THE COMPANY WITH EXPERIENCE IN
DIGITAL
POLYPHONIC
SYNTHESIS
RMI PIONEERS DIGITAL SYNTHESIS
Forgotten the last time you used a mechanical adding
machine? That's because everything is going DIGITAL! The
reason—a desire for increased accuracy inherent in digital
systems and high function density in a small, reliable, and
economical package. Articles have proclaimed digital
synthesis as the ultimate musical instrument system of the
future. RMI is in that future NOW and it works! Since
1971, our parent company, Allen Organ, has been marketing
musical instruments relying exclusively upon digital waveform
generation. This experience has given RMI the knowledge
to build a reliable, easily playable, and highly musical
instrument with sounds musicians are seeking. You will find
other companies just beginning to experiment while RMI's
digital ability is already well-established.
NEW TONAL FREEDOM
Free from sawtooth or pulse wave "mother tones" of earlier
synthesizers, RMI's digital system can create a wider range of
timbres with greater precision and absolute repeatability
Controls are binary—on/off. Gone are the approximations,
cr.t.ca adiustments and unrepeatable "patches" associated
W!th slidepots and knobs. Even the most complex effects
are quick and exact.
DIGITAL WAVEFORM GENERATION
An order of accuracy in control never before achieved.
To control sound is'to control waveshape. Therefore better ^
waveshape control means better sound control. KC-II ^
employs no audio oscillators. Instead, wqyeferms are pbtted
on an amplitude-versus-time graph. Points of intersection 1
on this grid are assigned binary code numbers representing \,
Jj*e ^F^0™11' ^ven $? fn°s* complex waveshapes can be
"frozen" for accurate reconstruction at a Uiter date. By
reading out the entire group of numbers dnd translating ^
them into relative voltages, at a rate of 440 times per
second, for example, a tone of middle "AV can be generated.
This tone will exhibit all timbre quality inherent in the
waveshape. Timbre can remain stable regardless of
frequency (pitch). Tracing problems, along with filters, are
eliminated. A whole new world of exotic sounds opens up
born realistic and • ^ - —
■■■■» ik ''■■■■■■■■■■■■■■■■■Si
PERMANENT WAVEFORM MEMORY
Years were spent working with musicians developing timbres
constituting useful and popular sounds. These timbres,
represented by 38 individual waveforms in binary code,
have been permanently stored in the memory of KC-II. In
live performance, these waveforms can be recalled instantly
either individually or mixed in groups:
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with the permanent memory^ Waveforms in any combination. ; ?
Programming can be up-dated by merely slipping another %
lone Card in and out. !:■.-• - - -
TONE CARD LIBRARY
Our Tone Card Library is to the musician what a paint store
is to an artist—it contains the materials in raw form.
Currently, cards number in the hundreds with new sounds and
variations under continual development. Each card contains
not only timbre information, but also precise amplitude
(R.M.S. value) and pitch data. Many cards are available in
multiple amplitudes for mixing a wide variety of relative
strengths. As many as 20 pitch references are available
from 16' through 1/2' and including such esoteric fractions as
2 2/7', 1 5/11', and 8/9'. Creativity potential is staggering.
TWELVE INDEPENDENT DIGITAL ENVELOPE
GENERATORS
Substantially increased control and musical merits are gained
over voltage-controlled predecessors while critical calibrations
are eliminated. Envelopes are plotted on amplitude-versus-
time grids much like our digital waveforms. As attack and
decay stages are "clocked", amplitude values rise and fall
in precise sequence creating envelope curves. Several
independent curves including an abrupt gating can be selected
in combinations. Envelope timing can occur from two sources:
1. Variable Rate Pedal
2. Key Frequency (scaled attack/decay: high notes
speak quickly, low notes speak slowly—12
independent rates possible simultaneously)
Clocking sources can switch automatically while crossing
from attack to decay ramps or upon key release. Also,
clocking can be stopped on specific voices to create "drones"
while others are free to play. Envelopes can be mixed to
obtain more complex curves or even envelope timbral
changes. Total independent polyphony and creativity
extend well beyond familiar ADSR devices.
NATURAL NOISES IN ACOUSTIC
INSTRUMENTS
Noises are a natural inherent characteristic of acoustic
instruments: the squeak of round-wrapped guitar strings, the
"chiff" of flutes and organ pipes, valve noises, air noises, etc.
Musicians have become accustomed to hearing these noises
integrated with the sounds of acoustic instruments. Remove
these noises and the resulting sound will be unnatural—too
perfect or sterile. Digital waveforms and envelopes
integrate certain subtle noises with the playing of each note
for a natural sound. As a result, KC-II seems to "breathe"
when played. Cello, viol, or any bowed string is another
example of this noise phenomenon. A well-rosined bow is
sticky. Now notice, like the bow, the long attack ramp
in the envelope graph is not smooth. There is a remarkable
similarity in the subtle noises generated by the bow and
slower digital envelopes. This factor adds to the excellence
of the KC-II strings.

SCALED ENVELOPES
Scaled envelopes are a natural phenomenon found in
acoustic instruments. High-pitched instruments (example:
piccolo, violin) tend to exhibit rapid attacks and decays due
to their small physical size. However, a large tuba or bass
viol would be much slower since it takes time for the air
inside the case to begin oscillation. Once set in motion, and
due to case resonances, oscillation continues slightly beyond
the time when the stimulus (blown air, bowing, etc.) is
removed. A large chord played on KC-II could have as
many as twelve different attack and decay rates
simultaneously. This feature lends great plausibility to
orchestral effects.
AUTHENTIC
BOWED
STRINGS
POLYPHONIC VOICE ASSIGNMENT—
12 VOICES
There is no "free lunch": the more you spend for each voice
generating unit, the more sophisticated, flexible and better
sounding it can be. Therefore, among keyboards in the
same financial ballpark, those with more voice generators
will, of necessity, have less control, and those with fewer
voice generators can afford more control (over each sound).
Also, the least control will come from systems whose generators
are hard-wired to each key—one for every note. Such
systems are inflexible and, in essence, are filtered organs.
For example, when playing a 6-note chord on a 61-note
organ approximately 9/10's of the tonal resources are lying
dormant. The longer the keyboard, the more generators
wasted. When you are paying for each generator, you
want a more cost-effective system. RMI has a new approach.
Survey your manual anatomy—ten fingers? KC-II provides
twelve voice generators (two more than you have fingers).
In fact, you probably average somewhere between four and
six voices at a time in most music (Bach did well with four).
Many interesting effects and "fat" sounds are created by
having multiple voices on each key. Dividing our twelve
voices between Divisions A and B, A and C, or A, B, and C
allows one, two, or even three voices per key. Selecting the
proper assignment mode for your music will keep most of the
voices speaking most of the time—an efficient use of your
tonal resources. Now, even simple chords can create big,
rich, and complex sounds.
per
Key (Total = 12 Voices
from 12 Keys)
Division A
12 Trumpets
Channel One (left audio)
Division A
6 Violins
Channel One (left audio)
Tunings "A" 440-
Division B
6 Violins
Channel Two (right audio)
Tuning: "A" 442
per
Key (Total = 12 Voices
from 6 Keys)
I CHAN. 1 I I CHAN. 2 I
DIGITAL CHORUS/VIBRATO
One of the beauties of acoustic instruments is their slight
imperfection in pitch when played in ensemble. KC-II has
stored this "imperfection" precisely for recreation of the
phenomenon. Chorus de-tuning or digital vibrato can be
selected individually for Divisions A, B, or C. Channel One
can have vibrato on a Flute Solo while non-vibrato Bells
emanate from Channel Two. Both digital and master pedal
vibratos are synchronized and rate adjustable
Division C
4 Bolls
Channel Two (right audio)
Percussion Envelope
Division A
. 4 Organ Pipes
Channel One (left audio)
Tuningi "A" 440
\
Division B
. 4 Organ Pipes
Channel Two (right audio)
Tuning: "A" 442
Three
Voices
Key (Total = 12 Voices
from 4 Keys)
ASSIGNMENT
EXAMPLES
CONTRASTING VOICES-
LIVE PERFORMANCE FLEXIBILITY
Predictable and accurate control over quick changes is the
secret to live performance. KC-II provides much of the
flexibility of double keyboards: contrasting envelopes and
waveshapes can be assigned opposite audio channels for
rapid control with pedal faders. Contrasting effects can even
be mixed in a single channel with a third effect on the
opposite channel, keeping your audience guessing. Fat and
rich bass lines from the lower end of the keyboard are
available simultaneously with clean and brilliant chords or
lead lines from the upper end—all without split keyboard
problems. Digital waveforms make it possible.
CHORUS TUNING
» ♦ ♦
LEFT
AUDIO
A44O
TUNING
A442
TUNING

PRESETS ALLOW RAPID-FIRE CHANGES
Strings—typical electric string machines are buried in the
mix while KC-ll's realism merits solo work. Proper waveshape
maintained to the extremities of the keyboard and
independent envelopes contribute authenticity. Details such
as variable phrased vibrato and variable attack/decay
(pedals) are musically convincing. Even string pizzicato can
be added by footswitch. Chords can be "latched" to free
hands. "Bowing noise" is the final touch.
Electric Organ—the old tone-wheel and drawbars sound
has been captured complete with third harmonic percussion
and two-speed rotary speakers. Staccato footswitch is
percussion cancel. Vibrato pedal is tremolo control.
Organ and Bells—very commercial. 1' sine tone pedal
variable from long wailing sustained percussion to a short
funky "popcorn" percussion—all on top of an organ sound.
Organ and Guitar—B-3 effect in Channel One with pedal
steel or rock guitar in Channel Two. Pitch Bender creates
slides up to a fourth. Pedal faders make rapid changes.
Horn—Rich, fat, and breathy.. Scaled attack/decay. Just
the raw material for "synthesizer licks" (pitch bends and
vibrato). Addition of percussion pedal creates piano.
Electric Piano—8' transpose is warm and realistic with
sustain pedal. 16' takes on an electric bass in lower end.
Latch pedal creates a mellow organ or holds notes or chords
while the remainder of the keyboard is free.
Clav—funky metallic sound (very popular). Decay is
pedal-variable from "loose" to "tight".
Jazz Flute and Clav—highly realistic metal flute contrasts
clav in opposite audio channel.
Alto Recorder and Harpsichord—wood flute contrasts
plucked strings in opposite audio channels. Exceptionally
delicate and articulate.
Bells—clanging realism due to KC-ll's forte in complex
waveforms and chorus tuning. Decay is pedal-variable.
Pipe Organ—diapason chorus with 4-rank mixture. The
Allen Organ heritage shines here.
Echo—notes repeat like tape echo, but in a different timbrr
one octave lower. Delay time is pedal-variable.
CUSf0M^5ET-UPSrf DO-IT-YOURSELF SOUNDS
While playing on a preset, you can create your own sounds
one tab at a time. When ready, turn off the preset and
your custom sound is on (presets override custom set-ups).
For further flexibility, your custom sounds can be added to
any preset with the Add Manual tab. You can play
non-stop for hours continually changing to new effects. Our
comprehensive Owner's Manual currently contains over 50
creative "patches". Some of the favorites are: Sax with
random over-blow, Vibes, Marimba, Steel Drum, Banjo,
Dynamic Brass (timbral change), Honky-Tonk, Choir, and
Abstracts. ~- .
PEDAL ASSEMBLY IS
INCLUDED
With a Polyphonic Synthesizer,
serious professional keyboard
people concentrate on their music
with both hands on the keys.
Attempts at reaching for controls
destroy the natural flow. Therefore,
musical expression such as Pitch
Bend, Vibrato, etc., must come from
the feet. KC-ll's Pedal Assembly is
included as an integral part of
the
instrument, not an accessory.
Musicians will find KC-II a full-time
instrument—much like driving a
sports car. Tooling through your
licks takes on new expression.
Envelopes can be compressed or
expanded right in the middle of
your most difficult runs. KC-II
responds as an extension of
your body.
PLUG-IN CIRCUITRY
0J£our belief that a musician who
iipalces a substantial investment in
Ja/najor keyboard relies upon that
^fcfrument. Expensive and lengthy
jSdown time" on the job is
; intolerable. KC-II functions are
gd$y|ded into five plug-in boards,
^ifce event of failure, a quick
^exchange plugs you back in
business. Pictured on the right is
^our main computer board—a "chip"
foff the old block below.
Rocky Mount Instruments, Inc.,
Sales Office: Macungie, Pa. 18062,
Subsidiary of Allen Organ Company
/ VARIABLE \
I from off \
/ through \
/CLASSICAL STRINGS^
/ to heavy
/ SYNTHESIZER LICKS
yv-nerates abrupt attacks & decays
acts as an envelope modifier
acts as an envelope sub-preset
* push ON/OFF with L.E.D. indicator
HOLES \
assembly
so peda/s j
do not /
"walk away" /
during /
performance /
STEREO FADERSl
cross fade \
from I
organ to guitar \
flute to clav I
etc., or '
add them together
CONTROLS: ~ ^-^
variable attack/decay rate
percussion decay rate S
sustain decay rate yr /
echo delay time jS /
jingle notes or chords
modifies other envelope functions
cross-fades preset chords
push ON/OFF with L.E.D. indicator
/a PERFECT FOURTH \
/ sharp or flat
spring loaded to assure
return to standard pitch
RMI's FAMOUS RUGGED
CONSTRUCTION AND QUALITY
Heritage dates back to 1939 with our parent, the
Allen Organ Company. Musicians are the benefactors.
The same quality level as Allen is maintained and
many parts are identical. For example, all control
tab legends are engraved. Our front panel is
routed out of wood. RMI keyboards are literally a
"piece of the rock" from giant four-manual consoles.
Key action is natural wood with individually-
adjustable tension, travel, and point-of-contact.
Our legs are sturdy, but quick and easy to set up.
Expensive extra travelling cases are unnecessary
with RMI because we build our instruments into an
enclosed case. We invite you to look inside any
instrument before you buy, particularly ours—
you will see the difference.
Rocky Mount Instruments are built to last.
PACKAGE .
Case: height 9-3/4", width 44", depth 24-1/2'
Legs: add 26-3/4" to height
Pedals: height 3", width 46", depth 13"
Power: 90 watts <Sb 117 vac—50/60 hz

7 *

Dear KC-11 Owner:
Congratulations! You have chosen a unique instrument that will no doubt
cause
you to stand out as a musician.
Your decision to purchase the Keyboard Computer was probably based on
the sounds you heard either on the demonstration record or in person at
a live demonstration. We would agree that the sound of an instrument is
its most important quality. Instant-action Presets controlling the most
popular sounds allow you quick access to a wide variety of effects, how
ever, the potential of this instrument extends far beyond the Presets.
We would like to see you realize the greatest return on your investment
by exploring the total potential of your Computer.
This Owner's Manual is a comprehensive collection of data gathered over
a period of years beginning in 1974. Contributions in the form of Set-Up
Sheets and ideas have been made by owners like yourself. Blank Set-Up
Sheets are provided for your convenience to jot down new sounds. If you
create some new Set-Ups you feel are unique, please send them our way -
the Owner's Manual is loose-leaf and we up-date it from time to time.
Finally, if you are to realize the full potential of your KC-11 you must
give the Owner's Manual a thorough reading - at least once. There is
much more to the Computer than meets the eye from the front panel.
Should you get in a bind understanding some part of the instrument, we
are as near as your phone (no collect calls, please).
Enjoy the knowledge that your sounds will eventually affect the music
business as have synthesizers. Good luck.
Sincerely,
Clark A. Ferguson
RMI Performing Artist

TABLE OF CONTENTS
Page Subj ect
1 INSTANT KC-II - OR HOW TO START PLAYING IMMEDIATELY WITHOUT MUCH READING
2 AUDIO REQUIREMENTS:
"Flat" Response
Type of Equipment
3 SETTING UP YOUR KC FOR PERFORMANCE
7 RMI 360 SERIES AMPLIFIER AND SPEAKER SYSTEMS
11 KC CONTROL FUNCTIONS - BRIEF DESCRIPTION
15 WAVEFORMS:
16 Tone Card Hole Designation (Clarinet - Wood 8T)
17 One Cycle of Clarinet - Wood 8! MOOR1084 (graph)
18 Waveform Symmetry
19 Tone Card Pitch Control
20 PITCHES:
21 Pitch Footage Chart
22 Pitch Characteristics and Usage
25 Pitch Characteristics and Usage Chart
27 FIXED VOICES:
29 Fixed Voices Chart
30 TONE CARDS:
R.M.S, Values
31 Custom Cards Polic>
32 Current RMI Tone Card Library Categories
35 Mixing Pulse Waves (graph)
36 Mixing Pulses to Create Staircase Waveform (graph)
37 Sax Set-Up: Random Tone Change and/or Octave Jump (graph)
38 VOICE COMBINATIONS (recommendations)
41 PROCESSORS
43 ENVELOPE GENERATION:
47 Long Attack/Normal Decay (graph)
48 Short Attack/Normal Decay (graph)
49 Percussion Decay (graph)
50 CHANNEL ASSIGNMENT - VOICES, PROCESSORS, 5 ENVELOPES (block diagram)
51 Pitch Generation
Add Channel Two
52 Chorus/Vibrato
53 Chorus Effect - Divisions "B" 5 f!C" (panel facsimile)
54 Envelopes

Page Subject
54 Fixed £ Alterable Voices
55 Processors
56 PROCESSOR AND ENVELOPE ASSIGNMENT COMBINATIONS:
57 Recommendations (panel facsimile)
59 KEYBOARD COMPUTER TECHNIQUE:
60 Instrumental Realism Styles
61 Presets: Strings
64 Electric Organ (B-3)
65 Organ § Bells
Organ § Guitar
67 Horn
68 Electric Piano
69 Clav
Jazz Flute § Clav
71 Alto Recorder § Harpsichord
Bells
v Pipe Organ
72 Echo
74 THE PEDALS:
Vibrato
Attack/Decay
75 Volume
Foot Switches: Latch, Staccato, Percussion, Sustain
76 Pitch Bender Technique
78 Transposer Tuning § Pitch Bender Controls
80 Model KC-II Pitch Bender Controls (schematic)
ORIGINAL MUSIC WRITTEN FOR KEYBOARD COMPUTER - COMPOSED BY CLARK FERGUSON
TRANSCRIBED BY RALPH SPOETTLE
SET-UP CHARTS (panel facsimiles):
The 12 Presets - Explanation
Add Manual - For Presets
Custom Set-Ups
25 Blank Set-Up Sheets
SERVICE MANUAL - SEE TABLE OF CONTENTS IN SERVICE MANUAL SECTION

INSTANT KC-II — OR HOW TO START PLAYING IMMEDIATELY
WITHOUT MUCH READING
1. Place all control tabs in NORMAL or OFF position - push top end,
2. If red LATCH or STACCATO lights are lit, push corresponding foot switch
to cancel.
3. Open CHANNEL 1-2 and CHANNEL 2 pedals - toe down all the way.
4. Place LEFT FOOT on VIBRATO pedal.
5. Place RIGHT FOOT on ATTACK-DECAY pedal.
(Do not allow your foot to catch on an adjacent pedal).
NOW, YOU ARE READY TO TRY THE PRESETS
1. Select one preset at a time - start with STRINGS.
2. Use 3-voice "open" harmony - large spaces between voices.
3. Notice you hear 2 strings playing for every key you hold - Chorus Tuning.
4. Adjust ATTACK-DECAY time (right foot) while repeating a chord - listen.
5. Add some VIBRATO (left foot) as each musical phrase builds.
6. Try TRANSPOSE 8 (under GENERALS) for high violins.
NOWf YOU ARE READY TO TRY OTHER PRESETS
1. Notice the word "priority11 and an arrow to the right. When more than one
preset is turned on, the one farthest to the right will be in operation.
2. As you change from one preset to the next, you will notice that adjustments
will be required in the ATTACK-DECAY time (right foot) to obtain realistic
musical results - experiment with extremes. Some presets will not be
affected by the ATTACK-DECAY pedal: Pipe Organ & Clav.
3. Some presets will sound best with VIBRATO added - STRINGS particularly.
4. Some presets have contrasting instruments in Stereo. Open and close
CHANNEL 1-2 and CHANNEL 2 pedals independently.
5. Experiment with effects LATCH, STACCATO, and SUSTAIN-PERC pedals have on
the presets.
THERE IS A LOT MORE TO THE COMPUTER THAN MEETS THE EYE
So, read your Owner's Manual.

RMI Keyboard Computer Audio Requirements
Probably the most unique single feature of the KC is its ability to control
waveshape and thereby control even the most complex harmonic content. When
one has paid substantially for such an instrument that can generate an
extremely wide range of sound, it would follow that the audio system through
which you will hear this instrument should also be of che same wide-range
calibre, if you are to hear what you paid for.
There are probably numerous excellent systems manufactured by many companies .
that would give successful results with the KC. Since we cannot investigate
all of them, here are some general guidelines to follow to make your own
choice.
The KC requires "flat" response. An absolutely flat system would respond
with equal efficiency at all frequencies of the audio range. The term Mflatlf
is in quotes, however, since it is not technically possible today to build
an absolutely flat system. This need not become a problem, but instead an
advantage. The most critical part of the range in creating the realism in
imitated instruments that the KC is so famous for is the mid-range and upper
frequencies. Frequencies lying in this area must remain in precise and
proper proportions to each other if realism is to be achieved. While the
lower end is certainly important to high fidelity, if lows tend to roll off
or drop out, most of the realism will still be present. The lower end pro
vides a sense of power - the listener feels the results on the floor and on
his or her chest and it adds emotion to the music. However, in many situ
ations where KC players work in a band, there is a bass player and the bass
portion of the spectrum is delegated to that instrument. Since the KC
player would not want to fight the bass player, a drop off in the bass
range of the KC audio system is a definite advantage even though it is not
flat. A KC performer doing a solo gig, however, would want plenty of bass
power since he would be called upon to create his own bass lines.
What type of equipment does flat response require? Almost without excep
tion flat response requires some form of multiple speaker system. Due to
efficiencies and inefficiencies in mechanical design, certain types of
speakers are more efficient operating in different portions of the audio
range. Of course, the end result is to have the entire range covered with
equal efficiency. In general, larger speakers cover the bass, medium size

cover the mid-range, and very small ones cover the upper end. No company
has ever successfully covered the entire range with one speaker.
Most bass speakers are of the paper cone variety, and a very common and
efficient size is fifteen inches. These speakers must be mounted in one of
several types of cabinets. Horn-loaded cabinets tend to be very efficient
by nature but in a rather narrow band of frequencies, causing a "boominess"
quality. Ducted or ported cabinets are a little less efficient, but their
efficiency is spread over a wider range of frequencies. Finally, sealed or
flair-suspension!l cabinets offer the very best in wide-range coverage of the
bass range; however, their efficiency is very poor causing them to require
substantial amounts of amplifier power for the same volume levels.
Mid-range speakers commonly used in the hi-fi industry are also of the paper
cone type, due to their physical ability to cover a given range with relatively
equal efficiency. Such devices as rubber or cloth edges further expand range
and ability to generate transients - so critical to percussive attacks. These
types of mid-range speakers are generally sealed from the rear and therefore
do not react with the cabinet in which they are installed. Horn-loaded com
pression drivers (known as mid-range horns) are more frequently used in the
P.A. and musical instrument business due to their well-known ability for
penetration. Once again, horns are highly-efficient but at the sacrifice of
wide range response, although some people will tell you they can be equalized
flat. Solo instruments, guitar and voice sound okay through horns due to the
fact that most of the audio being generated by these sources falls within the
range of the horn. However, full range instruments like the KC and particularly
"string11 keyboards sound like horn or brass sections when heard through horns.
Avoid using horn speakers when trying to achieve flat response for keyboards.
Tweeters is the term applied to upper range speakers and most hi-fi manu
facturers again stick with the paper cone or dome type for the same reasons
outlined before. Horn tweeters tend to become "peaky."
When choosing the speaker system for your KC, checkout the types of speakers
used and how many. You should try for all paper cones or dome type (avoiding
horns) and try for at least a three-way system - bass speaker, mid-range
speaker, and tweeter. Better systems will usually have more than one of
each mid-range and tweeter. If you are in doubt, try the KC Strings Preset
through the system you are considering. Can you imagine yourself in the

middle of a real string quartet, or does it sound electrically amplified?
Amplifiers should be chosen AFTER you have chosen your speaker system,
because speaker requirements have everything to do with amplifier power.
Obviously more and larger speakers will require more power; however, there
are other factors to consider - efficiency. Flat systems with crossovers
absorb the most power for the amount of volume they deliver (they are ineffi
cient), and generally, the flatter a system becomes, the more inefficient it
becomes. Of course, the flatter the system becomes, the better it tends to
sound to the ear. Power requirements go up and vown and so do cost, weight
and physical size. For most people a compromise must be made somewhere. Where
is the best place to compromise without sacrificing performance? Usually in
the bass end, since this is the range that requires the most amplifier power,
the
most expensive speakers, the largest cabinets, and creates the most weight.
Once you have made final decisions about your speaker system, make absolutely
sure that you purchase adequate amplifier power so that "clipping distortion11
does not occur on the heavy transients frequently generated by the KC or
during heavy bass passages. Remember, if you are playing in a band that
already has a bass player, you will not need as much bass power,
Bi-amping, tri-amping, quad-amping? These are terms applied to the technique
of using independent amplifiers for each speaker range. For example, a tri-
amp system would have three amplifiers - one for bass, one for mid-range,
and one for the tweeters. This technique does provide the ultimate in high
volume undistorted sound reproduction; however, the cost is quite high. If
money is no issue, this is no doubt the way to go.
Stereo? The KC is definitely conceived as a stereo instrument and certainly
there is no question that the very best results are achieved using dual
amplifiers driving dual speaker systems. However, there may be situations
where stereo is not needed, such as in film and video work or even some bands
using a mono P.A. system, particularly if volume levels are more critical
than tone quality.
RMI, realizing the requirements of an audio system made by the KC, has
designed an amplifier and speaker system particularly suited to these require
ments. The system is called a 360-K which includes one 360 amplifier head
with one K-180 five-speaker three-way cabinet and a switchable crossover for
mid-boost. The amplifier head has 180 watts RMS power. Two 360-K systems

are required for stereo. This 360-K System is excellent for any type of
keyboard instrument. In fact, you will hear sounds from your keyboards you
never heard before due to the "flat" response. You will find information on
this amplifier contained in this section on audio.
Setting Up Your KC for Performance. Assuming you have removed the cover and
unfolded the legs, you are ready to connect the pedals and audio. Locate the
metal jack panel under the KC on the right side. Note the polarizing key way
in the plug and jack for the pedal cable. Insert plug and screw retainer ring
to secure. To insure that the retainer ring does not "seize,11 back off one
quarter turn fromnsnug.ff Remaining are two quarter-inch phone jacks labeled
"1" and "2" - outputs for the left and right stereo channels. The output
impedance is around 150K ohms (very high) with the volume pedals full open,
and the level is low (like a dynamic microphone or a guitar). Two audio
cables are provided with your KC and these should always be used rather than
other types for two reasons: 1. RMI uses RG-59U transmission cable for low
loss of highs and reliability, and 2. RMI plugs are all-metal construction
with strain reliefs for long-lasting durability and freedom from hum. A
pre-araplifier will be required ahead of your power amplifier to boost the
signal - this feature is already incorporated in most amplifier heads and
mixers. The response curve should be essentially flat - '-.hat is, no EQ (no
cut or boost). Some microphone mixers have a high frequency boost built in -
find some way of eliminating or attenuating this high boost or it will cause
unnecessary buzz in the softer and more mellow KC sounds. Be sure the input
impedance of your amp or mixer is at least above 100k ohms. If not, add
resistance- in series with the "hot11 audio lead (this can be done in an adapter
box or inside the cable plug). If impedance is much lower than 100k, there
is a good possibility that the clock R.F. (radio frequency - 3-4meghz) will
travel down the audio line into the amplifier causing a "zinging" or whining
noise in the audio. No harm will be caused, but it can become distracting if
the levels are high enough. A clue to the existence of this phenomena is that
it changes pitch with the Pitch Bender pedal.
Now, you should be ready to set levels. If you are running mono, both channels
will be mixed into one at the mixer - do not use a "Y" connector or closing
the volume pedal of one channel will short out the other. In fact, make sure
that your mixer has isolation between the "hot" leads of the inputs or
shorting will still occur (only the very cheapest mixers do not have input

isolation). Select the Electric Organ Preset, open Channel One and Channel
Two pedals fully, and hold a three-note chord between the third and fourth
octaves and hold one note in the bass in the first octave (you can even
activate the Sustain and Latch pedals to hold the chord while you make
adjustments and listen at various locations in the room). First make sure
all EQ controls (if there are any) are in the "zero11 or Mflatff position -
you want to hear exactly what the KC is generating, no more, no less. If
you are in mono, turn the Channel One input volume up to about two-thirds
of what you would 1\ke to be full volume, then set Channel Two to equal
it - with both together, you should achieve full volume; if not, adjust
both accordingly. It is important that both channels be of equal volume so
that certain effects between channels can be created. It is also of equal
importance that both channels have the same degree of "flatness" in their
response. Channel balancing is even more critical in stereo. Once you
think you have a volume and EQ balance, sit down at the KC and make a quick
pedal switch from One to Two - are they the same (there will be a small amount
of residual percussion decay added to Channel One, making the channels not
exactly equal). Now, change to the Strings Preset - both channels should be
exactly equal. How are the highs? Does it sound like sitting in the middle
of a string quartet? If it doesn't, there is work to be done. Speaker place
ment is very important since the highs, so critical to strings, are very
directional. Point the speakers and/or tweeters specifically toward both the
performer (yourself) and the audience or whoever is to hear it. Bass speakers
should always be placed next to a large plane that is part of the room - sit
ting on the floor and/or against a wall. It is in this manner that the bass
"couples" with the room. The Electric Piano Preset has the most transient
generation and the Electric Organ Preset has the most mid-range transient
generation - use these presets, one, then the other, to check for amplifier
"clipping distortion" (use same chord and bass as before, only keep repeating).
Set both channels equal and as high as you want before distortion sets in on
the attack of the chord. Be advised that amplifier "clipping distortion" is
not only an unpleasant sound, particularly in transistor amplifiers, but it
also generates an infinite order of super high frequency odd harmonics that
can easily channel the amplifier's power into destroying tweeters (a mishap
not uncommon with today's high power amplifiers).

360
SERIES
PLIFIER
— and —
G-180
B-180
K-180
SPEAKER
SYSTEMS
No matter what instrument you play the RMI 360 Amplifier Head will deliver the output.
A unique Equalizer System in this head gives the performer unusually wide versatility from
"flat" response for many keyboards to the customized "peaks" and "valleys" needed for Bass
and Guitar. All you do is select the proper RMI Speaker System for your job: model G-180
with JBL High Efficiency for High Volume applications like Guitar or RMI Electra-Pianos,
model B-180 with "Rock-Solid Bottom" for your Bass Axe, or model K-180 with "Flat"
response necessary for the RMI Keyboard Computer or Synthesizers.
ROCKY MOUNT INSTRUMENTS,
215/965-9801
ROCKY MOUNT, N.C. 27801

RMI MODEL 360 AMPLIFIER HEAD
Two Input Channels: Variable Gain Input circuitry (unlike standard attenuators) allows
an unusually wide range of input levels without sacrificing dynamic range of the instrument.
Input clipping is virtually eliminated. Both High and Low Impedance input signals are
accepted without loss of level or gain in distortion.
Input Sensitivity: 47mv—4.0 volts RMS yields full output into 4 ohms.
Input Impedance: 300k ohms Channel One and Channel Two inputs (independent).
Input Both Channels: Parallel Input designed for use with one guitar to allow flexibility of
using EQ controls of both channels together. This feature also permits rapid change between
preset EQ settings. Input Impedance 150k ohms.
Equalization Controls: Placing all EQ controls at the 12 o'clock position renders the
system "flat". For guitar, special "active" circuitry provides extreme "boost" and "cut"
deviations. Variable Frequency Control for the critical Mid-Range Band offers a new area
of creativity in generating Response Contours. All EQ controls are duplicated for each
channel.
Bass Cut & Boost: ± 18db @ 100hz with 6db/octave slope
Treble Cut & Boost: ± 20db @ 10khz with 6db/octave slope
Mid-Range Cut & Boost: ± 14db @ Top End Band
+ 22db @ -80db @ center of Bottom End Band
Variable Mid-Range Frequency: Top End Band 176-900hz with 6db/octave slope
Bottom End Band 112-470hz with 6db/octave slope
Reverb: Master Level Control affects both channels. Three-way switch turns reverb on
Channel One, Channel Two, or Both. Jack for Foot Switch control on rear panel. Unique
Constant-Current Drive circuit assures quiet clean response. Unit is particularly insensitive
to physical shock.
Amplification: 180 watts RMS into 4 ohms @ less than 1% THD
110 watts RMS into 8 ohms @ less than 1% THD
IM .15% @ 4 ohms with 1.0 volt input/20 volts composite output
IM .075% @ 8 ohms with 1.0 volt input/20 volts composite output
Bandwidth ± ldb @ 30hz - 125khz
Solid-State and Short-Circuit Proof
Power Requirements: 117VAC 50/60hz-full output draws approximately 300 watts
Package: Height 9-1/2" — Width 21-5/8" — Depth 13-3/8" — Weight 31 lbs.
RMI SPEAKER SYSTEMS model K-180
Model G-180: JBL 15" Full Range with Two Tweeters. A highly
efficient unit with extra available Mid-Range Energy. Recom
mended for High Volume applications with RMI Electra-Pianos or
other instruments. Dual Parallel Jacks allow use of two model
G-180's in parallel for additional power. 8 ohms each.
^^^ TWFFTFR3
Model B-180: Single 15" Heavy-Duty Bass Speaker for use with ™ ■*■*■*»
Bass Guitar, Manual Bass, or Organ Bass Pedals. Special flat
wound copper ribbon voice coil vented for dissipation of heat.
4 ohms.
Model K-180: Five-Speaker Three-Way System providing the
"Flat" response required by RMI Keyboard Computer or Synthe
sizers. Crossover switchable from "Flat" to "Mid-Boost" for
extra "Punch". Two Tweeters, Two Mid-Range, One 15" Bass
Ported and Tuned for ultimate efficiency. 4 ohms.
Package: Height 31-1/2" — Width 21-5/8" — Depth 13-3/8" — Weight 62 lbs. approxi
mate. Rugged corners, recessed handles, convenient size and weight for ease in carrying.
Ported and Tuned for maximum use of bottom end. Applies to all models.
[ ROCKY MOUNT INSTRUMENTS, INC. Sales Office: Macungie, Pa. 18062 Phone: [phone]
© 1977
MIDS ^^
o o
TUNED PORT

360 AUDIO SYSTEMS: DIFFERENCES IN APPLICATIONS
The RMI 360 Amplifier has been designed with the power and wide tonal range
to allow the musician great amplifying flexibility. When this amplifier is
matched with the proper speaker cabinet, an optimal Audio S3'stem is
developed for each application.
The 360-G Audio System, consisting of a 360 Amplifier and a G180 Cabinet,
is a high efficiency system which is recommended for guitars and many
keyboards when higher amplitude is needed. The RMI Electra Piano, among
other electric pianos, will not be able to achieve highest volume with the
360-K amplifier/speaker due to heavy "piano attack". When highest volume
is required, always use the 360G. We have included the same tweeters
used in the !IK!I cabinet in the flGM cabinet. The 360-G also has a 1511 JBL
speaker which is highly efficient --it concentrates amplifier power in the
mid-range area where the human ear is most sensitive. This increase in
volume is achieved at some sacrifice of "flat11 response, particularly in
the bass area. However, by properly manipulating the equalizer controls
on the amplifier, the system can be made more "flat11.
A musician who needs even more volume can use two G180 speaker cabinets
with the 360 amplifier head -- the cabinets are 8 ohms and two can be plugged
in parallel for 4 ohm operation to increase volume. There are two jacks
on the back of the cabinet. The K180, however, is of 4 ohms impedance,
cUid only one can be used with each amplifier.
The 360-B Audio System, consisting of a 36 0 Amplifier and a B180 Cabinet,
allows the Bass guitarist to achieve a solid sound from a system that is
practical in size.
Remember, when highest volume is an important part of the musician1 s needs,
the 360-G should be used. When "flat" response is the most important
requirement, the 360-K should be chosen.
The 360-K Audio System, consisting of a 360 Amplifier and a K180 Cabinet,
was designed for "flat" response, specifically to make the Keyboard
Computer sound its best. In order to achieve "flat" response in an audio
system, the sound must be able to spread over the entire audio range with
equal efficiency. The model 360-K does exactly that. In the process the
power of the amplifier is also spread over the entire audio range. The
model 360-K will make most keyboard instruments sound better. However,
there is a point of coition - some customers may require even more volume.
With the crossover switch on the K180 speaker cabinet in the "Mid-Boost"
position and the Equalizer Controls adjusted for less bass and extra treble

and mid-range, a higher level of volume can be created with the Keyboard
Computer and many synthesizers using the 360-K. Other keyboard
instruments may require a more efficient speaker cabinet. For these
cases we advise the G180 Cabinet.
WARNING - K180 Cabinet: Due to the large amount of power available from
the 360 amplifier, prolonged use at high volume with excessively boosted
mid or treble may cause crossover and/or tweeter damage to the K180 cabinet.
1/14/77