Friday, March 03, 2017
Limaflo Motomouth Eurorack Coded CV Sedra+Espinoza Morphing Formant Filter
Currently seeking funding on Kickstarter here.
"Following on from the successful Kickstarter project last year (the Chicago Mk1 limited edition synthesizer) [featured here], and also the positive experience with the backers (who were all really terrific), I've decided to realise a further project, this time focussed around the exciting Eurorack Modular Synthesizer format.
Motomouth is an analogue 3-Band, Sedra + Espinoza Bandpass Filter (DABP) with resonant frequencies that are tuned to the same (similar) resonant frequencies found in the human mouth and nose cavities, and these can be varied, independently, to form different 'mouth shapes', to emulate vowels such as A, E, I, O and U.
Motomouth can emulate 16 vowels and 'morph' or 'glide' between each vowel using a single Control Voltage input (1V/Oct), and a Gate to 'snap' to each vowel when required.
Two of the bands (F1 and F2) are used to form the mouth cavity, and the third band (F3) is used to from the nasal cavity, which is reasonably static. Varying F3 makes little significant difference 'in the mix', but having it is important.
The single Control Voltage is decoded to control F1 and F2 independently, because the frequency bands for each vowel are not proportional to each other over the vowel range. So Motomouth has learned how to 'speak', so to speak, but it still needs to learn more, and that's were you come in.
OBJECTIVE (see also 'PROJECT STATUS')
The task is to raise funds for Motomouth's mechanical components and the PCBs in a larger quantity, at a lower cost, with the goal of eventually selling a range of 'boutique' modules through distribution. The funds will also be used to purchase some PCB's for preliminary testing and to triple-check. The PCB's (and mechanical assembly) for this Kickstarter project, will be lovingly hand populated and constructed, but the funds will also be useful for converting Motomouth over to surface mount technology for machine production later, or if the quantity estimate 'avalanches' (which I'm not anticipating).
Single CV to control and set vowel shapes.
Automatic Morphing and morphing rates to each vowel.
Gate operated snap to each vowel when required.
Sedra+Espinoza Analogue Filter design for a high, sharp Q value and a 12 dB/octave roll-off slope.
Plays well from a monophonic keyboard or Midi Keyboard through a Midi to CV/Gate converter.
Works great with a CV Step Sequencer.
Filter and vowel mode selection using the same single CV input.
The system is managed by two ATMEGA328P Microcontrollers."
See the Kickstarter campaign here for additional details.