To trace the meaning of articulation it is first necessary to be aware of the difference between the notation of music (note) and its actual performance (tone). A note is a symbol of a musical event. Its attributes indicate pitch, length, loudness, onset and timbre. A tone, by contrast, is the actual physical event in a performance. Its attributes are pitch, duration and so forth that all correspond to the referring indications of the note. Expression in music performances touches deviations from tone attributes and note indications. Both timing and dynamics shape musical structure by influencing tone onsets and loudness values, respectively. Articulation as the forming of the single tone adds further deviations (e.g.an accent on a crescendo). This concerns all tone features, which are loudness, pitch, duration, envelope and also timbre. The following descriptions briefly introduce the parameter space articulation is involved in:-
- Envelope: A tone can consist of the four parts attack, decay, sustain and release. Every part can show different preportions or even be absent. On the whole they describe the loudness progression over a single tone.
- Duration: Is the time from tone-onset to its offset, either proportional to the inter onset interval or in absolute time
- Loudness Deviations: Independently from the dynamic shape of a musical section, certain articulations influence loudness.
- Timber deviations: Some articlulation instructions particularly refer to playing techniques (pizzicato, hammered bow strokes). They affect timbre changes that are neither exclusively caused by loudness changes nor depend on instrumentation.
- Intonation deviations: Similar to loudness and timbre, different articulations may influence intonation
Articulation can affect one or more of these tone features.
The ASM322 is usually inserted at the output of an envelope shaper and adds velocity dynamics. In addition, as well as just adding level shift, it also fattens the envelope without altering the timing dynamics of the envelope.
When [VELOCITY] input is 0V, an [ENVELOPE] of 0-10V will be copied to [OUT] as 0-5V. When [VELOCITY] is 10V, the same [ENVELOPE] input will be copied to [OUT] as 0-10V. Intermediate values will, however, be non-linear.
The ASM322 can also be used for other applications including:-
- Keyboard. Adding velocity dynamics from keyboard/sequencer control. Use a MIDI keyboard and a MIDI-CV Interface with VELOCITY output and connect to the [VELOCITY] input.
- Sequencer. Adding dynamic interest to automated music. Connect a suitable 'control voltage' such as from an LFO, to the [VELOCITY] input.
- Animator. As an animator for audio waves. Feed a sawtooth, triangle or sine audio wave into the [ENVELOPE] input and an LFO into the [VELOCITY]. The result will be a kind of PWM chorus effect.
- Wind Controller. As a waveshaper for wind controllers. Feed a sawtooth into the [ENVELOPE] input, and the Breath Control or Aftertouch signal into the [VELOCITY]. Blowing harder will increase the level a bit, but also square the wave a little: this is a little like the effect that the Marrietta Variophon used for brass and wind: a narrower but louder pulse.
References: Expressive Articulation for Synthetic Music Performances. Tilo Hahnel and Axel Berndt