1979 - DAO

  • $775.00


Digital oscillator with envelope and VCA/LPG

The Algorithmic Oscillator is a Buchla-format VCO based on Plaits by Mutable Instruments. The successor to the 1979 DAO, the AO has more knobs, more parameters, and more I/O than the DAO plus new features not present on Plaits. With an internal envelope generator and a simulated LPG with adjustable vactrol response, the AO is an ideal standalone voice module for small Buchla systems.

 

Core Features

  • High-fidelity digital oscillator (48 kHz, 16 bit)
  • 16 synthesis algorithms (see the Algorithm List below)
  • Auxiliary output with complementary audio signal
  • Internal VCF/A with variable LPG mode
  • Voltage-controlled decay envelope*
  • Dedicated knobs for envelope decay and VCF/A amplitude*
  • Pitch quantizer (12-TET and Octave options)*
  • Inverting attenuators for all CV inputs (0-10V range)*
  • Envelope CV output (0-10V range)*

*Upgraded features not available on Plaits

Algorithm List

Dual oscillator. Mix of two analog-style waveforms: a variable-width pulse and a second oscillator which can be continuously waveshaped from triangle to a glitchy sawtooth. Turn the Timbre knob fully to the left to silence the pulse, or turn the Morph knob fully to the right to silence the tri-saw waveform. This technique can be used to take one or both waveforms out of the mix. The AUX output is the sum of the two waveforms with hard sync applied.
Timbre:
Pulse width shaper
Harmonic:
Relative detuning ratio
Morph:
Tri-saw shaper

Waveshaping oscillator. An asymmetric triangle wave is routed through a waveshaper and a wavefolder. The AUX output is similar but uses a different wavefolding method. Both outputs are reminiscent of classic Buchla/Serge textures.
Timbre:
Waveshaper waveform
Harmonic:
Wavefolder amount
Morph:
Waveform asymmetry

2-Operator FM. Two sine oscillators with cross-modulation of phase. The AUX output is a suboscillator derived from the base frequency.
Timbre:
Modulation index
Harmonic:
Frequency ratio
Morph:
Feedback level/type

Granular formant oscillator. Simulation of formants using the multiplication, addition, and synchronization of sine wave segments. The AUX output is a simulation of filtered waveforms by windowed sine waves
Timbre:
Formant frequency
Harmonic:
Frequency ratio
Morph:
Formant width/shape

Harmonic oscillator. An additive mixture of harmonically-related sine waves. The AUX output uses specific frequency ratios (1, 2, 3, 4, 6, 8, 10, 12) which emulate the drawbars on old organ/string synths.
Timbre:
Formant frequency
Harmonic:
Frequency ratio
Morph:
Formant width/shape

Wavetable oscillator. Four banks of waveforms arranged in an 8x8 matrix. Left of center, the Harmonic knob scans through the four banks with interpolation between waveforms. Right of center, the waveforms are not interpolated. The AUX output is a lo-fi version of the main output with 5-bit resolution.
Timbre:
Row index (X-axis)
Harmonic:
Bank selection
Morph:
Column index (Y-axis)

Four-note chords. Tuned waveforms emulate vintage string/organ machines with four-note polyphony. The AUX output provides only the root note of the chord.
Timbre:
Inversion/Transposition
Harmonic:
Chord type
Morph:
Waveform type

Speech synthesis. A collection of speech synthesis algorithms. Harmonic scans through various models including formant filtering, SAM, and LPC vowels, then goes through several banks of LPC words. The AUX output provides an unfiltered version of the underlying vocalization waveform.
Timbre:
Species selection
Harmonic:
Crossfade speech models
Morph:
Phoneme/word selection

Granular supersaw. A swarm of 8 enveloped sawtooth waves. The AUX output provides the same but with sine waves. For the classic "supersaw" sound, turn Morph fully to the right and apply subtle CV randomization to the Timbre and Harmonic inputs.
Timbre:
Grain density
Harmonic:
Frequency randomization
Morph:
Grain duration/overlap

Filtered noise. Variable-clock white noise processed by a morphing resonant filter. The tuned resonance will properly track CVs applied to the Pitch input. The AUX output uses two bandpass filters whose relationship is controlled by the Harmonic knob.
Timbre:
Clock frequency
Harmonic:
Filter morph (LP>BP>HP)
Morph:
Filter resonance

Particle noise. Dust noise processed by networks of all-pass or band-pass filters. The AUX output is the raw noise without processing.
Timbre:
Particle density
Harmonic:
Frequency randomization
Morph:
Filter type

Inharmonic strings. Similar to the "red mode" from Mutable's Rings with three voices of polyphony. This model requires an excitation signal. There are three ways to generate this signal. When the Trig input is switched off, an internal noise source will randomly trigger the exciter. If external CV is patched to the Pitch/Freq jacks, pitch changes over one semitone will also trigger the exciter. If the Trig jack is patched (and enabled with the Trig switch), the exciter will only be triggered when an external pulse is received. The AUX output is the raw excitation signal, which will be perceived as a short click or burst of noise.
Timbre:
Exciter filter/brightness
Harmonic:
(In)harmonics
Morph:
Decay time

Modal resonator. Similar to the "green mode" from Rings. Like the "Inharmonic strings" algorithm above, this algorithm also requires an exciation signal. All of the Trig and Pitch logic above also applies to this algorithm. The AUX output is the raw excitation signal.
Timbre:
Exciter filter/brightness
Harmonic:
Material selection
Morph:
Decay time

Analog bass drum. Low-frequency percussive model derived from analog hardware simulation. The AUX output provides a bass drum using an alternate DSP model.
Timbre:
Lowpass filter cutoff
Harmonic:
Envelope attack + drive
Morph:
Decay time

Analog snare drum. High-frequency percussive model derived from analog hardware simulation. The AUX output provides a snare drum using an alternate DSP model.
Timbre:
Modal morphing
Harmonic:
Harmonic/noise balance
Morph:
Decay time

Analog cymbal. Generates metallic tones derived from six square wave oscillators mixed with a noise component, routed through a VCA modeled on a low-fidelity transistor circuit. The AUX output uses three ring-modulated square waves.
Timbre:
Highpass filter cutoff
Harmonic:
Harmonic/noise balance
Morph:
Decay time

The last five algorithms in the red bank have unique responses to external triggers.

Algorithms D/E will be triggered randomly by an internal noise source if the Trig switch is off. Turn the Trig switch on to disable the noise source and switch to external triggers only. Note that with the Trig switch off and a trigger source patched in, events will be triggered by both the internal noise source and external triggers.

Algorithms F/G/H (kick/snare/cymbal) have their own tone-shaping envelope, which is controlled by the Morph knob. External triggers will activate that envelope. Turning on the Trig switch will change the Amplitude response.

The other 11 algorithms have a more direct response to triggers. With the Trig switch off, triggers will activate the envelope, which will open the VCA. Turn the Trig switch on to activate the LPG. The envelope will open the VCA while the trigger will ping a simulated vactrol model. The ringing time of the vactrol model can be adjusted. Press the Trig switch and turn the Amplitude knob. From left to right, the knob will morph from a short ring time, through a more sustained and gradual decay, to a more linear VCA. The amplifier response is visualized on the upper row of LEDs.