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Sound design with the Elektron Monomachine

Constant-time slides

Roland's TB-303 is a synthesizer with a number of somewhat unique features that may be the source the deep reverence many have for the instrument. One of these features is its ability to program consistently musical slides between two sequenced notes, where the pitch changes smoothly and this smooth transition finishes just in time for the next note in the sequence no matter the interval between the notes. This type of slide is called a "constant time" slide and is most similar to how a real musician would smoothly transition between two notes on a real instrument. A constant time slide is different to how slides are typically implemented in synthesizers, where the slide rate is programmed and this rate may or may not be fast enough to transition between the two notes before the second note is supposed to be played.

After spending some time with the Monomachine, you may wonder how to program some nice constant-time slides on it. The portamento parameter on the amplification page seems like it might do, but if you spend some time experimenting with it, you will find that it's not quite right. Any tempo change in your sequence will make the slides sound off time.

The Monomachine can do constant-time slides of locked sound parameters, but not of pitch natively. The way around this is to use an LFO to modify pitch and then use the Monomachine's parameter slides on the LFO depth. For example, here's a recipe to program a one octave constant time pitch slide:

On any track LFO:
PAGE: PTCH
DEST: 4OCT
TRIG: HALF
WAVE: SQR
MULT: 1X
SPD: 0
INTL: 0
DPTH: 0

Once the above is setup, use parameter to locks to lock the LFO's depth to zero on the sequencer step where you want the slide to begin. Then lock the LFO's depth to 124 (not 127!) on the step on which you want the slide to finish. From here, hold the function button and push the rightmost pattern bank button with the label "slide" under it to enter slide edit mode. Put a slide trig on the step you want the slide to begin on.

Run the sequencer, and you should hear that the pitch between the two sequencer steps will slide up and get to one octave above the original pitch just as the sequencer lands on the step for which we programmed to finish above. You can adjust the tempo all you want at this point, the slide will always finish at the right time.

Programming pitch slides this way can be a little tricky if you want to slide up or down to a pitch that isn't an octave away. Here's a list of some common intervals and the associated LFO settings needed to get there:

Octave up:
LFO DEST: 4OCT
LFO DPTH: 124

Perfect fifth up:
LFO DEST: 4OCT
LFO DPTH: 73

Perfect fourth up:
LFO DEST: 2OCT
LFO DPTH: 100

Major third up:
LFO DEST: 2OCT
LFO DPTH: 82

Minor third up:
LFO DEST: 1OCT
LFO DPTH: 60

You can slide down in pitch by letting the WAVE parameter of the LFO be ISQR.