Composition
beatZap composes each song based on a single genre:
A genre in beatZap refers to a set of parameters that are
used by the composer to create a song. These parameters are set in such a
way that when the right combination of musicians are playing, the rhythm sounds
like a typical song of the genre.
One of the jobs of the composer is to create rhythms for the musicians:
Musicians: For each song there are a group of musicians. Each
musician plays a single rhythm but can switch instruments as it plays. Musicians
are divided into monotonic and polytonic, since rhythms appropriate to each
type of instrument are often different.
Musician rhythms are designed to suit specific types of instrument:
Instruments: Sounds loaded into beatZap
are converted into
instruments. These are split into two groups:
Monotonic – Can only play one note, like drums or other percussion
instruments. This distinction is arbitrary since some percussion instruments can
play multiple notes. In those cases, beatZap would classify them as Polytonic.
Polytonic – Can play an octave of notes. Within this group some can
play chords – i.e. more than one note at the same time. (Some polytonic
instruments are too complex to sound good playing chords.)
Instrument types are further subdivided for a total of 12 aspects:
| MonoTonic |
Polytonic |
| Bass - an instrument that plays low notes
(usually < 60 Hz) |
Bass - an instrument that plays low notes
(usually < 60 Hz) |
| Rhythm - an instrument that plays a
simple regular backup |
Rhythm - an instrument that plays a
simple regular backup |
| Lead - an instrument that plays a more
irregular style |
Lead - an instrument that plays a more
irregular style |
| Slow - an instrument that has a longer
sound sample (usually > 0.25 sec) |
Slow - an instrument that has a longer
sound sample (usually > 1 sec) |
| Fast - an instrument that has a short
sound sample (usually < 0.1 sec) |
Fast - an instrument that has a short
sound sample (usually < 0.1 sec) |
| Chorded - usually the same as rhythm |
Chorded - an instrument that can play
chords. During performance the corresponding musician will play
chords rather than single notes. |
Current Limitations
- Each polytonic instrument is restricted to a single octave.
- Time signatures are limited to 2/4 through 6/4, with a choice of 12ths or
16ths.
- Triplets mixed with quarter notes are not supported.
- Beats Per Minute range is 60 to 140 for each genre. During
performance this can be adjusted +/-30.
- There are no controls for note sequences.
- The genre parameters cannot be changed.
- The composer is limited to about 30,000 different songs of each genre.
Parameter settings for each genre restrict that number further.
- Multi-part sounds are not available.
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