Sujet Alesis ION - OS 1.03

Citation : 1.03 - Released November, 2003

A. KNOWN BUGS:

none.

B. BUGS FIXED:

Oscillator Aliasing – The maximum (highest) fundamental frequency of the oscillators was mistakenly set much higher than the anti-aliasing filters. This made it possible to transpose the oscillators to a point where only the aliasing frequencies were heard. The maximum fundamental frequency has been fixed, so that it complements the anti-aliasing filters. Some additional optimizations have been made to the oscillator anti-aliasing algorithm which increased the (alias-free) range of the oscillators by ~ one octave.

C. FEATURE UPDATES AND ENHANCEMENTS

New Filters! – Three new filter types have been added.

OP 4-Pole Highpass - This filter is based on our “MG” 4-pole lowpass filter model. It has a steeper cut-off and more extreme resonance than the “OB” highpass. Like the “MG”, it will self-oscillate when the resonance is turned all the way up. It can thus be used as a fourth (or fifth) oscillator.
Comb 3 – Based on a different design than Comb’s 1 and 2, it has deeper notches and more pronounced resonance.
Comb 4 – Similar to Comb3, but with negative feedback. This will oscillate and even clip when the resonance is turned up.