Vacuform

Vacuum Tube Multimode Filter

Vacuform is a 12 dB multimode filter designed for Eurorack modular music synthesizer format, utilizing vacuum tubes as active elements. It is intended to generate filtered sound with complex relations and control parameter interdependencies, adding more details to the sound compared to more common transistorized designs. In short: this filter is LIVING, having lots of sweet spots to discover!
As it is common with vacuum tube audio designs, sonic qualities and subtleties varies slightly between units, and that kind of diversity is perfectly fine.

Specs / Controls
•Discrete, vacuum tube multimode filter
•Simultaneous lowpass, bandpass and highpass inputs
•Cutoff frequency manually controlled or via two CV inputs, from which one can be attenuated; •Exponential control
•Resonance amount manually controlled or via attenuated CV input; Can be set to oscillation
•AC-Coupled Output with level attenuation
•Widely varying degree of inherent soft saturation
•Resonant output waveform highly dependent on input signal anplitude

Requirements
•Vacuum tubes are thermionic devices; They require high temperatures in order to work, which correlates with high power consumption. Tubes that size usually need hundreds of milliamps each - that means your Eurorack system needs to provide LOTS of current - 890mA @ 5V in this case. Alternatively, an external power source can be used to offload your PSU.
•Also, please note that vacuum tube modules are generating significant heat that may alter performance of neighbouring temperature sensitive modules.

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