Frap Tools - Falistri
The FALISTRI is a fully analog multipurpose movement manager designed to generate and edit voltages to easily accomplish any patch.
The module can be divided in two big parts: in the upper two thirds of the panel take place two specular function generators, while the lower third is composed by a dual cascaded frequency divider, a linear slew limiter and a four quadrant multiplier.
The generators are made to quickly and intuitively achieve the function needed, providing several outputs and inputs to dynamically change their times and trigs. The main peculiarity in this design is the way shapes are managed:
- times are independent from shapes – when sculpting an envelope, you can freely morph from Logarithmic to Linear to Exponential slope, without changing the time needed to complete Rise or Fall (and their Loop time when used as oscillator);
- shapes are exclusive per each stage – you can have Logarithmic Rise and Logarithmic Fall, Linear Attack and Logarithmic Fall or any other combination of the three modes, and of course any blending in between these shapes, allowing deep sculptures of sound when used as Control Voltage as well as audio source.
The time switch scales the time factor on both rise and fall stages in each generator.
Both manual button (for hands-on control) and external trigger/gate Input are available, and are used in the three possible play modes:
- Loop – where end of fall stage triggers the start of rise, incoming triggers are not needed, but if present reset the rise;
- Transient – only the low-to-high transition of the trigger/gate signal is used to start the rise stage, while fall stage is automatically recalled at the end of rise;
- Sustained – the low-to-high transition of the trigger/gate signal is used to start the rise stage, while the fall stage is trigger by the high-to-low transition of the Trigger/Gate signal.
A Gate input for switching from Loop to Transient and vice versa is also present.
Quadrature (Q) mode combines yellow and green function generators with the following stages connections:
- end of yellow rise triggers start of green rise
- end of green rise triggers start of yellow fall
- end of yellow fall triggers start of green fall
yellow and green
- unipolar 0V/+10V
- bipolar -5V/+5V
- attenuverted -10V/0/+10V
- Analog OR or Maximum function between yellow and green
yellow and green
- End of Rise
- End of Fall
Cascaded Frequency Dividers
Also known as flip/flop or sub-octave processor, each of these changes its logic state each time a low to high transition is performed. Sections are semi-normalled in order to achieve 1/2 and 1/4 outputs from a single input. Output range switches are useful to obtain unipolar (0V/+10V) or bipolar signals (-5V/+5V).
When an audio signal is used it works as a sub-octave generator (square/pulse preferred). When a clock is used it works as a clock divider. Random clocks from SAPÈL create interesting variable-length sequences of gates.
Four Quadrant Multiplier
Also known as ring modulator, balanced modulator, or ThruZero VCA, this sections precisely multiplies two signals, making any sort of amplitude/loudness modulation possible.
With an exceptional linearity, and a bandwidth from DC to more than 20KHz, the result of this operation is completely up to the sources in use: from a simple dual unipolar multiplication (one quadrant), to unipolar / bipolar (two quadrants), up to any kind of dual bipolar multiplication (four quadrants).
The two inlets are semi-normalled to yellow and green generators. The 4 led matrix shows which of the quadrant is currently in use.
It may also be used as a VCA, with linear CV response.
Linear Slew Limiter
Also known as portamento/glide when using a pitched CV, this processor comes into play when any voltage smoothing is needed. With independent rise and fall slew rates, it is possible to precisely smooth any kind of voltage transition.