KARMA 2: Duration Control Reference
[in progress]
Scenario
You'd like to know more about how the Duration parameters work in KARMA, and how they are attached to the control surface for Real-Time Control. For example, in many of the GE RTC Models (the Control Surface assignments for the KARMA Mode), Slider 3 will be labeled "Duration Control" - what does this do exactly?
Background
"Duration Control" refers in general to shortening or lengthening the duration of the notes that KARMA generates. [in progress]
Duration Control
In many of the GE RTC Models (the Control Surface assignments for the KARMA Mode), Slider 3 will be labeled "Duration Control". This is typically hooked up to a GE RT Parameter named "Duration: Duration Value". In a Combi, you will find this parameter in the Module's individual Control Layer, and in the Master Layer, the convention is to have it as Slider 3 as well, controlling at least one Module, but usually controlling the Duration of several Modules simultaneously.
The way that the Duration Value parameter functions is controlled by another parameter that is often not accessible inside the Korg keyboard itself, which is the Duration Mode. There are several different modes, and the Duration Value parameter can function differently in each of them, as discussed below.
From the KARMA Software Manual
[Duration Mode] (popup menu) [0…7]
Selects one of several modes of operation for generating durations in the current Phase.
0: Poly Extend (Value range: 1 ~ 800 %)
Each note will sustain until the next generation of the same note, or until that note is no longer a part of the Note Series
(caused by playing a new chord, for example). For example, if the notes to a CMaj chord are sustaining and the chord is
changed to a CMinor, only the Es will be damped. Especially useful for fingerpicked and strummed guitar effects. Certain
steps may be “damped” by using the Duration Pattern Grid to indicate a duration value shorter than the current Rhythm
Pattern value. The “Duration Value” parameter is used to specify a percentage of the Duration Pattern value, making it
shorter or longer by a certain amount. For example, if the Rhythm Pattern is generating quarter notes, any step in the
Duration Pattern (as modified by the Duration Value) that is shorter than a quarter note will cause the notes (and all
sustaining notes at that time) to have the specified duration. This is useful for simulating the technique of strumming and
damping certain chords within the progression. Any value in a Duration Pattern step (as modified by the Duration Value)
that is longer than the current Rhythm Pattern value will be ignored, and the notes will sustain as described above. The
Duration Value field specifies a percentage of the overall value (1 ~ 800 %) - therefore, values less than 100% will
shorten the duration represented by the Pattern Step, and values greater than 100% will lengthen it.
1: Poly Extend/Damped (Value range: 1 ~ 800 %)
The same as above, except all sustaining notes will be damped when the chord changes, not just notes that are no longer in
the Note Series.
2: Mono Extend (Value range: 1 ~ 800 %)
The same as above, except each note is sustained until the next note (of any pitch) is generated. When used with clusters,
only one note in a cluster will actually be sustained. This can be used to simulate a monophonic instrument, for example,
although other modes here can also do that depending on how you set the parameters.
3: Timed (Value range: 1 ~ 5000 ms)
The Duration Value field is used to specify the duration of the generated notes, in milliseconds (1 ~ 5000 ms). All notes
will therefore have the same length. Note that this is independent of the current tempo - if it is set to 50 ms, it will
always be 50 ms, regardless of tempo.
4: Rhythm Overlap (Value range: -500 ~ 500 ms)
The Duration Value field is used to specify an amount by which each note or cluster will overlap or be separated from the
next note or cluster, in milliseconds (-500 ~ 500 ms). Note that this relates to the Rhythm Pattern values. Positive
values cause overlapping; negative values cause separation. For example, a setting of -20 ensures that all notes will
extend and be separated from the next notes by 20 ms regardless of the actual rhythm the notes are generated with, or
the current tempo. Note that while the Rhythm Pattern values themselves are relative to tempo, the value specified here
is not. Using the example setting of -20, there will always be a gap of 20 ms between notes regardless of the tempo.
5: Rhythm % (Value range: 1 ~ 800 %)
The Duration Value field is used to specify a percentage of the rhythmic value a note is generated with to use as a duration
(1 ~ 800%). Note that this relates to the Rhythm Pattern values. The actual time is then calculated on the fly, taking into
account the current tempo. For example, with a setting of 50%, if the Rhythm Pattern specifies a string of 8th notes,
they will appear to be generated as a string of 16th notes separated by 16th note rests (each 8th note will have the
duration of a 16th note, or 50%). Note that this value is therefore relative to tempo.
6: Pattern Overlap (Value range: -500 ~ 500 ms)
The Duration Pattern Grid is used to construct a Duration Pattern, in a similar fashion to the Rhythm Pattern. Each step in
the pattern indicates the duration for notes that are currently to be generated. The Duration Value field is used to specify
an amount by which to increase or decrease the pattern values, in milliseconds (-500 ~ 500 ms). This can be used to set
up a certain Duration Pattern, and then vary in real-time the “gate-time” of each note in the pattern simultaneously. For
example, if the Duration Pattern is generating 16th - 8th at a tempo of 120 BPM, the notes would have the durations of
125 ms, 250 ms, etc. If the Value field is -20, they would be generated as 105 ms, 230 ms, etc. Note that while the
Duration Pattern values themselves are relative to tempo, the value specified here is not. Using the example setting of
-20, the notes will always be 20 ms shorter regardless of the tempo.
7: Pattern % (Value range: 1 ~ 800 %)
The Duration Pattern Grid is used to construct a Duration Pattern, in a similar fashion to the Rhythm Pattern. Each step in
the pattern indicates the duration for notes that are currently to be generated. The Duration Value field is used to specify
a percentage by which to increase or decrease the pattern values (1 ~ 800%). This can be also be used to set up a certain
Duration Pattern, and then vary in real-time the “gate-time” of each note in the pattern simultaneously, similar to the
previous option. For example, if the Duration Pattern is generating 16th - 8th at a tempo of 120 BPM, the notes would
have the durations of 125 ms, 250 ms, etc. If the Value field is 80%, they would be generated as 100 ms, 200 ms, etc.
Note that this value is therefore relative to tempo.
Duration Control (Percentage)
As referenced in the video for Chapter 22 of the House 101 Combi Creation Series, the following diagram shows the effect of the Duration Value when the Duration Mode is "Rhythm Percent" or "Pattern Percent":
Assuming the Rhythm Pattern is generating Quarter Notes, and the Duration Pattern is either set to Quarter Notes as well with Duration Mode "Pattern %", or the Duration Mode is set to "Rhythm %", then the results are as follows:
Duration Value = 100% - Durations extend the full length of the Quarter Note.
Duration Value = 200% - Durations extend the length of a Half Note (x 2), overlapping the next note.
Duration Value = 50% - Durations extend the length of an Eight Note (x .5).
Duration Value = 25% - Durations extend the length of a Sixteenth Note (x .25).
GE RTP: Force Mono
In the area of "duration modification", a GE RT Parameter that is quite useful is "GE: Force Mono". In many of the GEs, it can be found on Switch 1 of the GE's RTC Model.
Force Mono does two things:
- Forces the GE to only generate one note at a time, regardless of how the other parameters are set. You may have the GE set to be generate clusters of notes, or many notes with the Melodic Repeat parameters; turning on Force Mono instantly thins out the phrase to a monophonic line.
- Does not allow overlapping durations. In other words, if a note is set to extend beyond the beginning of the next note in the phrase, it will be chopped at that point, so that they do not overlap. The note will extend up to the next note, but not overlap it.
This can be very useful for a number of things:
- Monophonic programs - most monophonic programs, if played polyphonically by KARMA, will exhibit very strange glitching sounds and generally not sound very pleasant. Turning on Force Mono on the Module Layer of the GE that is playing that timbre solves all those problems instantly. Secondly, even if KARMA is generating only a single note at a time, if you set the Duration Control so that the notes overlap, a program that is set to "Mono Legato Retrigger" will not retrigger any new notes. This can sound cool, or can sound bad. So by turning on the Force Mono switch or GE RTP, you prevent durations from overlapping and each note will be guaranteed to retrigger.
- Bass programs - typically, except in rare cases, you would never want the bass to play more than a single note at a time. Turning on Force Mono guarantees this will not happen, and then you can freely use the Repeat parameters to generate extra notes that will fill in the spaces between other notes in the pattern and create more exciting variations - without having multiple notes playing at once. In fact, it is reasonable to say that you should rarely ever use the Repeat parameters with a bass without having Force Mono turned on - but you have the power to decide!
- Scene Variaions with polyphonic timbres - even with polyphonic timbres in the upper melodic ranges, it can be very cool to turn on this parameter with the Melodic Repeat parameters generating extra transposed notes, and let KARMA turn it into a single note melody line. This can be especially effective with the slower/sparse Rhythm Patterns, where there is space for the repeated notes to fill in the spaces between the generated notes.
- Thinning out KARMA - this can be used as a general "note-thinner" when there's too much going on.
Duration Templates
Occasionally, you will see one of these two Duration Template-changing parameter variations assigned to the GE RTP for a KARMA Module, and perhaps assigned to the Control Surface as part of a Modules' RTC Model:
- Duration Template
- Duration Templte + Restore
Typically, this parameter will be assigned in conjunction with the same type of parameter from the Rhythm Group, such that operating the control changes the Rhythm Template and the Duration Template at the same time, to the same value.
Duration Patterns and Rhythm Patterns have an identical pattern grid in KARMA Software, so the Templates can be identically constructed.The Duration Templates Bank ROM A contains the exact same Templates as the Rhythm Templates Bank ROM A that is shown and discussed in detail in this article:
KARMA 2: Rhythm Template Reference
Notes & Tips
This article is referenced by the Karma-Lab video tutorial series:
House 101: Combi Creation Series, in Chapter 22: Slider 3 - Duration.
The video features in-depth discussion and examples of configuring the KARMA Master Layer to control Duration for the four Modules, including the use of the Force Mono parameter.