Brenso is Frap Tools’ primary analog source of articulated waveforms whose degree of entanglement can be precisely set by the musician.

Its concept developed from a reflection on the very meaning of the word ‘complex,’ which comes from the Latin verb plector, literally meaning ‘to braid’, or ‘to weave.’ The purpose of Brenso is to update the usual approach to ‘complex oscillator’ by offering many threads to be woven together, rather than a pre-defined plait of controls and waveforms: this to improve clarity, manageability and offer more sonic options to the artist.

Brenso consists of three sections: two for sound generation (yellow and green), and one for sound processing (white and red).

The generation sections allow control over the two triangle-core oscillators, which can be modulated from external sources and can modulate each other’s frequency too. The frequency modulation can be any combination of exponential and/or linear thru zero.

The processing section is composed of a waveshaping section (white) and a last stage of amplitude modulation (red): the first provides further degrees of modulation using two parallel wave-shapers and includes PWM, blends these two with a mixer and everything is passed into a wave folder with symmetry control and a dedicated clock input with shapeable nonlinear behavior.

The result of this is passed into an amplitude modulation section (red) which can be unbalanced (AM) or balanced (RM).

The white section modulations inputs are semi-normalled by a timbre bus, which is semi-normalled to the green sine wave.

By default, the green oscillator modulates the yellow one through an internal semi-normalization, which, however, can be ‘broken’ anywhere throughout the routing according to the musician’s needs.