An Overview of
Strum Acoustic
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2
An Overview of
Strum Acoustic
Strum Acoustic
is a synthesizer which was designed with the goal of enabling keyboard players to
easily create realistic guitar tracks. This is a task which is usually difficult to achieve due to the
very different nature of these two types of instruments.
Strum
was therefore designed to reproduce
not only the sounding mechanism of a guitar but also the main elements of the playing technique
of a guitar player.
Very generally playing on a guitar can be described in terms of fretting hand (usually left hand)
and picking hand (usually right hand) techniques. The fretting hand is used to fix the chords or
notes played on the different strings of the guitar while the picking hand is used to set the different
strings into vibration and therefore play melodies or strumming patterns. In
Strum
, these functions
have been integrated into a chord detection, voicing, and strumming module.
2.1
Chord Detection and Voicing
Chords played on a keyboard and a guitar share the same name but are played or voiced differently.
Because of the tuning of the strings on a guitar, the notes of the chord are not usually played
in the same order as on a keyboard and the range of the notes is usually different, notes may
also be repeated. Furthermore, the same chords can be played in different positions on the guitar
depending on the playing or musical style. This specific way of playing chords on a guitar is very
characteristic of the tone and sound of the instrument. It is therefore very important, in order to
obtain a realistic guitar sound, to play chords as a guitar player would rather than how they are
played on the keyboard.
The voicing of chords for the guitar is performed in two steps by
Strum
. A chord played on the
keyboard is first interpreted by the chord detection module in order to determine which chord was
played on the keyboard.
Strum
then finds a guitar voicing corresponding to this chord. In other
words,
Strum
finds how a guitar player would have played this particular chord.
When chords are played on the keyboard, the order of the notes above the root is not taken
into account by the chord detection engine. This implies that you can play the chords as you know
them on the keyboard without having to know or learn special voicings used by guitar players. For
example, you could play chords in close position with the left or right hand, you could also play
the root with the left hand and the rest of the chord with the right hand or play the chords with
the notes spread across both hands.
Strum
will take care of finding the right voicing and playing
position on the guitar depending on the settings of the chord type and playing position controls as
described in section 4.6
The name of the chord detected as well as the specific voicing chosen by
Strum
is displayed in
the fretboard located in the lower portion of the graphical interface. Note that the voicing chosen by
Strum
varies depending on the chord type chosen by the user as is described in Section 4.6.
Strum
will try to detect a chord as soon as three or more keys are depressed on the keyboard. Otherwise
Strum
will assume that a melody or interval is played. Please refer to section 11 for a list of the
chords detected by
Strum
.
