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.
No more tuning issues during a performance!
Every oscillator has a button that locks its coarse frequency to the current value. From this moment on, every twist of the ‘Coarse’ knob will be ineffective (but The Fine knob is still available, from small adjustments on the fly!).
Analog Thru-Zero Triangle Cores
BRENSO’s oscillators are exceptionally stable and provide rich harmonic content. This happens thanks to the two thru-zero triangle cores, which guarantee the most playable behavior and the best response to audio-rate modulation.
You won’t need to find a sweet spot because BRENSO is calibrated to sound ‘as expected’ in any setting!
Linear and/or Exponential FM
Many controls allow for complex and detailed FM sound shaping. It is possible to set the amount of exponential and linear thru-zero FM independently per each oscillator and control their amount of ‘deviation’ through two separate knobs or CV inputs.
(The green oscillator can also work at sub-audio rate, and can therefore become a super complex LFO!)
Four Expanded Modulation Buses
BRENSO’s ‘complex’ signal path is expanded on the front panel and grouped in four ‘modulation buses’: two for modulating frequencies, one for modulating timbre and one for AM and RM.
The green oscillator is always the semi-normalled modulator, but any other source can be used.
Original Timbre Shaping Design
The timbre modulation section has been designed from scratch and offers a versatile blend of two wavefolders, a waveshaper, and a PWM circuit.
A dedicated VCA controls the global amount of modulation to be sent to each modulation section, but the semi-normalization can be broken anytime.
We designed from scratch an analog circuit that, when excited by an external trig, opens the wavefolder above its maximum level and then closes it down with a non-linear slope, whose length can be manually regulated.
This solution can generate percussive tones with a very
- Two analog ‘thru-zero’ triangle-core oscillators
- Coarse frequency lock function per oscillator
- Eight waveform outputs, four per oscillator
- Linear ‘Thru-Zero’ Frequency Modulation (TZFM)
- Independently mixable Linear and Exponential FM per oscillator
- Flip Sync (the green oscillator can be sync’ed to the yellow one)
- Lock Sync on both oscillators
- Balanced or unbalanced modulation (AM / RM)
- Original timbre shaping section
- Explicit signal flow
