Soundfiles
AM In: Rhythm Machine; Output: Sine/Triangle – Oscillator frequency manually controlled |
AM In: Rhythm Machine; Output: Sine/Triangle – Frequency CVs in: Sequencer and LFO |
AM In: Rhythm Machine; Output: Triangle with FSK (Ramp) – F2 CVin: LFO |
2 XR22 VCOs cross-patched FSK In ⇔Square Out – AM In: Rhythm machine; Frequency CVs in: Sequencer |
Low frequency mode – F CVin: Envelope Generator; 1.AM in: KorgMS20 VCO; 2. Frequency modulation of KorgMS20 VCO with XR22 triangle out |
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Documentation |
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AM (Amplitude Modulation)
The triangle/sinewave output amplitude varies linearly with the control voltage applied to „AM in“. The modulation amount can be adjusted with knob ‚AM In‘. Negative CV’s will cause phase inversion of the triangle/sinewave output.
Examples:
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Ring modulation with external triangle signal | VCO volume control with external envelope signal | AM in connected to triangle/sinewave output (feedback) |
About FSK (Frequency Shift Keying)
The frequency of the XR22 VCO is controlled by two independent control sections F1 and F2 with their each independent manual frequency controls and CV inputs; either one or the other of these routes can be selected by a logic signal applied on socket „FSKin“ and/or by switch „FSK“.
Examples:
a) Depending on the logic state of FSK control , either only F1 (with knobs „F1“ and CVins „F1“) or only F2 (with knobs „F2“ and CVins „F2“) is active |
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b) In the low position of switch „FSK“ the FSK input is connected to the VCO’s own squarewave output and the oscillator frequency-shifts itself.
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c) By applying an external logic signal on input „FSK in“ (with switch „FSK“ in the middle position) the oscillator switches between F1 and F2 |
About Switch „Σcom→CVF2“
With this switch in upper position, both frequency control routes F1 and F2 (with their frequency knobs and CVins) are complete independently.
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