Spectral processing and polyphonic voicing for Eurorack format
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€ 599,00 € 499,17 + VAT
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TheUnknown Devices Eisei Quad Satellite System (Black) is a Eurorack module designed to bring spectral processing and polyphonic voicing into a deeply creative and performative dimension. Its architecture is built around four interconnected satellites designed to filter, harmonize, shape and resynthesize any incoming audio material, or to generate autonomous sound content via internal oscillators.
The result is a highly original instrument, capable of combining the musicality of spectral processors with the flexibility of harmonic oscillators, with a user interface that is intelligent, playful and oriented toward sound exploration.
The core of Eisei Quad Satellite System consists of 4 satellites, each equipped with 20-band filterbank, internal pulse oscillator and dedicated IN / OUT connections. This structure enables dynamic and layered signal processing, working simultaneously on multiple harmonic relationships and multiple timbre scenarios.
Global controls allow the four filter banks to be moved and animated as they flow within a spectral data table called Datum. The overall behavior resembles an ever-evolving ecosystem, ideal for creating organic textures, iridescent timbres and complex harmonizations.
One of the most distinctive features of the module is the Datum system. This is not traditional audio sampling, but a memory of spectral movements generated from the signal acquired during recording. Basically, the audio is analyzed through a filterbank with dedicated envelope followers for each band, and these variations are stored as automations to be reused later.
Eisei can store up to 8 Datums, which can be recalled at any time to reactivate and reinterpret filterbank behavior. This approach opens up very different sonic navigation from classic sampling: instead of playing an audio file, the module reanimates the spectral fingerprint of the recorded material, allowing new combinations of harmony, filtering, and motion.
Each satellite moves along its own orbit and reads the contents of the Datum with independent speed and direction. The most effective analogy is that of four heads sliding on a disk, each with a different position and speed. This makes it possible to create interwoven harmonic rhythms, controlled phase shifts, and continuously changing spectral loops.
The Orbit control allows you to change the speed and direction of each satellite individually or all of them together, while the Time wheel allows you to position yourself at a precise point in the orbit or navigate it manually. This makes Eisei extremely performative both in sound design and during live performance.
The Key 1V/Oct input acts as a frequency offset for the satellites, affecting both filterbanks and internal oscillators. Depending on the patch, it can be used to obtain melodic lines or complex sweeps assimilated to a multi comb filter.
The Spread parameter defines the degree of interaction between the satellites. Fully closed, the four elements work in unison on the same spectrum segment; increasing the control moves toward more and more articulated harmonic ratios, until distributions rich in unpredictable and musically interesting interactions are achieved.
Each satellite integrates a powerful Lens engine for precise control of the filter bands. In one direction, a focused, fluttery resonant band is obtained; in the other, an increasingly wide harmonic range opens up. In the more extreme zones the behavior becomes deliberately unconventional, with constantly redefining resonant configurations that greatly expand the timbral potential of the module.
The Warp section provides four tools to further push sound transformation. SHIFT generates a translational copy of the spectral configuration, TANH switches from soft distortion to brick clipping, SHAPE intervenes on the pulse width of the internal oscillators, and FEED introduces feedback into the system.
Any signal sent to a satellite input passes through the relevant filterbank, which is shaped by both Datum and Lens. In the absence of an input signal, the internal pulse oscillators kick in, allowing the module to also operate as a stand-alone sound source. The inputs can also be pinged, further expanding the patching possibilities.
TheUnknown Devices Eisei Quad Satellite System (Black) is designed for those seeking an out-of-the-box tool in the Eurorack landscape: a module capable of blending spectral analysis, harmonization, polyrhythmic movement and resynthesis into a highly expressive interface. It is an ideal solution for sound designers, experimental producers, and electronic musicians who want to build novel sound worlds from audio material, modulations, and complex harmonic relationships.
Technical Specifications.
Depth
18 mm
Width
18 hp
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