Music Editors for Small Computers
source Creative Computing, Februari 1981
by Rebecca T. Mercuri, RCA, David Sarnoff
Reasearch Center Princeton, NJ 08540
An abundance of music editors for small computers have recently appeared
on the market. At RCA's David Sarnoff Research Center,
where I an involved with computer music experimentation, I have had the
opportunity to compare these systems.
The presently available music editors appear to fall into three
-Text editors which enable the user to directly enter a music file in a
program like format.
-Editors which display musical notation,
but require the user to enter the notes using an ASCII keyboard.
-Graphic editors where entry of notes directly on the music staves is
made possible by cursor manipulation.
The VIP's system could be called a machine-language editor since it
requires the user to directly input hexadecimal codes for
each of the notes, each hex word specifying both the pitch and duration
of one note. Musicraft and Orchestra-8O both take this
idea one step further, and permit the user to input notes as they would
be read aloud from conventional music. For example,
A3H would indicate a 440 Hz half note.
Since both of these systems are similar to standard text editors,
features have been incorporated which make it easy to manipulate
the music program. Insertion and deletion procedures can utilize line
numbers, and looping, segmentation and external calls to
other portions of the program are processes available to the user.
Both Musicraft and Orchestra-8O require compilation of the music program
before playback, but an interesting feature of the
Orchestra-8O editor allows the tempo to be changed during play by
depressing number combinations on the keyboard. This feature
enables the piece to be heard at various speeds: These may be adopted
into the program text at a later time.
The MMI and Atari systems use ASCII input information similar to the
Musicraft and Orchestra-80 systems, but provide a visual
staff display for editing and playback. MMI utilizes a full four-voice
display and requires that all notes in each chord be written
vertically during editing. In the display-and-play mode, the score is
scrolled from right to left, and note durations may not
always be sounded precisely. In the play mode, there is no video
display, but all rhythms are correctly performed.
Atari permits the independent writing of up to nine separate phrases.
The arrange mode enables the user to insert these phrases
into any of the four voices. In addition, the volume of each phrase may
be changed each time it is called. Looping can be used in
order to implement repeats or rounds. The color display used in editing
assists the user in specifying the octave for each note.
On playback, only one voice at a time may be displayed, the display
voice being selected by the user.
Considering the rapid development of the personal computer industry, it
should soon be possible to construct music editors which
bear a striking resemblance to printed music, and can also be used in
real-time performance. My photograph of the "ideal" music
editor demonstrates the high level of readability which is presently
possible using the Apple II graphics display. Notes were
input using a light pen, and sufficient space is available between
staves to permit insertion of text and dynamics markings.
The black-on-white display further enhances the similarity to printed
notation. Let me remind the reader that this editor is only
in the development stage and is not commercially available.
KL-4M, Supersound, ALP, and Mountain Hardware all offer music editors
which permit cursor manipulation and note insertion directly
on the musical staff.
The Visible Music Monitor provided with the KL-4M DAC Board permits
fourpart harmonic input for PET ICBM Computers. The notes
are displayed horizontally, but grouped into chords with small lines.
The cursor can be moved up or down to change the pitch of
notes, and may also be moved right or left for insertion or deletion
purposes. Due to display requirements of the PET, the notation
appears much like that used in medieval music, but this does not detract
much from its readability.
Persons familiar with the VIP system will recognize the Super Sound name
in reference to the four-channel music player. At RCA,
an experimental prototype music editor for the VIP was developed. The
VIP four-channel Super Sound has the same music-playing
features as the prototype Supersound editor. The major difference is
that with the VIP, notes and measures must be handcoded
into memory, while the Supersound editor permits graphic entry of notes.
Another feature of the prototype involves the use of
the note cursor. As the note is moved up or down in halfstep increments
on the staff, the pitch is also heard. Future availability
of this editor will most likely depend on user interest; information may
be obtained from RCA Customer Service.
The ALF system is similar to the two editors I mentioned previously, in
that it permits cursor manipulation directly on the musical
staff. In addition, it incorporates many of the features of the text
editors such as subroutine calls and recursiveness. Meters,
key signatures, envelopes, volumes, and tempi can all be redefined at
any point in the music, thus providing the capability for
inventiveness and flexibility in musical interpretations. The pitch of
notes is heard as they are entered, providing immediate
auditory feedback for the user.
In addition, measure bars are automatically inserted by the editor.
Notes which exceed the measure
boundaries are tied over into the subsequent measure. The ALF system
resolves the problem of real-time music display by utilizing
a set of horizontal bars. As the notes are played, a small rectangle
moves across each bar, and its position relative to middle C
may be viewed. The color of the rectangle is dependent upon the volume
of the note. It is my understand- ing that ALF is now
marketing a single nine-voice board which has a six-(rather than eight-)
octave range, and a 28 db dynamic range (instead of 78 db
for the 3-voice board).
The Mountain Hardware system utilizes 16 oscillators in order to obtain
high-quality polyphonic instruments. Instead of specifying
a monophonic voice, the user may select one of six instruments which
have been preset. Of course, the number of notes played at
anyone time must not exceed sixteen. This editor permits single or
double stave notation utilizing the treble, bass, tenor and alto
clefs. A wide range of dynamic and tempo resets are also available,
which may be inserted throughout the music.
A light pen (which is provided) may be used to access the menu. Version
#1.1, which I viewed, did not provide the software support
which I understand will be available in future versions. For instance,
it is not yet possible for the user to create his/her own
instrument tables in order to augment those that are supplied. It may be
useful to review this system again at a later date when
more software becomes available. I regret that I was unable to obtain a
picture of Mountain Hardware's unique display.
a 37-point comparison of eight available music
The following chart is a 37-point comparison of eight available music
editors, a VIP-compatible editor prototype, and what I feel
would be the "ideal" music editor.
The music editors in this chart have been listed in order of increasing
complexity , and grouped according to the categories
mentioned above. Increased complexity does not imply that these editors
are harder to use; in fact, the reverse is often the case.
I have avoided subjective factors (e.g. which is best?) so that the
reader will be able to peruse that chart and determine which
system suits his/her present needs.
It is important to note that the cost listed for each editor can be
deceptive, and should therefore be considered only in
conjunction with the list of the equipment required. Some of the less
expensive systems demand extensive hardware support; but,
on the other hand, a number of the systems have special circuitry which
cuts costs for the user.
Although all efforts were made to com- plete this chart, not all needed
information was available. Where no information was
available on a specific topic "NI" was used. "None" was only used if the
product did not incorporate a particular feature.
There were also occasional discrepancies between information presented
in user's manuals and by the software representatives of
the various music editors (or by the editors' performances alone). 0