****************** Formantor (Stereo) ****************** Description ~~~~~~~~~~~ Here is a little demo-track, where all sounds are from with Formantor, only a bit of reverb got added and some mastering was done in the DAW: https://soundcloud.com/taitekatto/formantor-for-tbd The track mainly features feedbacklike tones as well as some of the typical formant based sounds on which the name of the instrument obviously is based on. The idea of Formantor is to have a simple yet fun to control synthesizer combining a Phase Distortion oscillator, a Squarewave oscillator with optional pulse width modulation, a vowel-filter, a resonator, a tremolo and a volume EG. The basic signal-flow is similar to classical synths like a Mini Moog with sections like OSC->Filter->LFO->VCA/EG Yet every of those components is used in a bit more unconventional way. This applies to the features that can be controlled as well as the sounds that can be achieved. You can have chant-like vowels as well as quite extreme overdrive / feedback loaded sounds and interesting modulations on various aspects of the sound including sample and hold modulation. Also lush and slowly evolving tones are possible. There are no stereo-effects or similar, instead the stereo-option is used to provide a possibility for direct out of the voices/oscillators-mix to allow additional treatment with other modules. Please note that adjusting the main volume can be very important, because the instrument has a wide loudness range. For lower tones it will be suitable to raise the global volume, but be aware that you may have to lower it for louder tones to avoid overdrive, unless that is what you are looking for. Formantor uses a resonant comb-filter, three state variable bandpass-filters and a Phase Distortion synth by Carlos Laguna Ruiz implemented in his VULT language, the PD-synth can be found here: `*https://github.com/modlfo/teensy-vult-example* `__ The code originally was intended as an add-on to the Teensy Audio library and got modified to be used with the TBD along with the aforementioned filters from VULT-examples by using the VULT compiler. For more details on the topic please look here: https://github.com/modlfo/vult For the formant-filter Open Source code by alex@smartelectronix.com and got used, as found here: https://www.musicdsp.org/en/latest/Filters/110-formant-filter.html Also interpolations on that code by Antonio Grazioli got used: https://github.com/antoniograzioli/Autodafe Parameters ~~~~~~~~~~ Section 1: “Global (Quantizer relative to Master Tune!)” - Gate/Trigger n/y - Master Pitch (map CV here) - Master Tune +- 1200 Cent (Adjust to your needs, especially in combination with formant-selection by notes or if CV is quantized to half-tones as below) - Quantize CV to chromatic tuning n/y - Master Volume (Please lower in case you encounter unwanted distortion) Section 2: “Voices” - Voices direct out (out-1) n/y (This may be welcome if you want to treat the oscillators with other modules as well) - PD Pitch - PD Tune - PD PitchMod Amount - Phase Distortion Amount (see description of “simulating a resonant filter” here: https://en.wikipedia.org/wiki/Phase_distortion_synthesis) - PD WaveFolding Amount (Wave Folder effect on the PD-Oscillator) - SQW Pitch - SQW Tune - PD-PitchMod and PWM speed - PWM intensity for SQW Osc Section 3: “AM / Mixer” - Amplitude Modulation active n/y - PD Osc<->AM PD with Sine from SQW - SQW Osc<->AM SQW with PD - PD Oscillator volume - SQW Oscillator volume Section 4: “Formant-Filter ('Key logic': Keys trigger the formants (A..E.I..O..U / R1-R12)” - Formant Filter n/y - 'Key logic' on n/y - Formant selection (A..E.I..O..U / R1-R12) - New random formant for selection n/y - Formant Filter Amount - Resonator active (switch to random formants) n/y - Resonator Frequency - Resonator Tone - Resonator Q - Resonator Amount Section 5: “Tremolo” - Tremolo active n/y - Enable only with ADSR Gate n/y - Attack - Release - Tremolo uses SQW n/y - Tremolo Speed - Tremolo Amount - Tremolo after formant filter n/y - PD-Mod uses SQW n/y - Modulate PD Tone Amount - S&H-Modulate Resonator Amount - S&H-Modulate PD Tone Amount Section 6: “Volume Envelope” - Volume envelope active n/y - Attack - Decay - ADSR n/y - Sustain - Release - Slow EG n/y - Envelope to Phase PD-OSC Usage / Patch Ideas ~~~~~~~~~~~~~~~~~~~ 1. Standalone sound generator, playing the formants - optionally via the keyboard 1. Standalone sound generator, using the Resonator, note that there are very interesting feedback-sounds possible when the resonance is high. 1. Combination of formants and Resonator. Note that in this combination you can select new random formants for the currently selected formant (by slider on GUI or via keyboard) 1. Use the Tremolo creatively with any of the combinations above, including Sample&Hold on PD amount and similar. Note that the tremolo can be delayed via Attack and Release once it’s activated/deactivated via a separate button. 1. Use the Volume envelope, including changing the PD-amount in time, similar to a filter-envelope. 1. Use the PD-Oscillator with slow pitch-modulation in combination with slow PWM on the Square Wave Oscillator and just a bit of the resonator for lush, slowly evolving tones, for instance to play slow melodies. 1. Use Formantor additionally as a pure Oscillator source via secondary audio output “out-1”. In combination with the options from above via “out-0” interesting combinations are possible, especially when you connect additional modules to “out-1”.