Frequency Shifter (Needs Modulator)

This module needs a perfect quadratur VCO to work. I recommend my full equipped FS-Shifter with high quality component and A110-4 TZ-VCO from Doepfer. It is a perfect duo!
If you like this version please ask me.

1. Hilbert Transformation Filter for incoming signal, DOM fitler (B. Hutchings, Haible)

2. Two precision multiplier for sin / cosin transformation (AD633) Mixer for up- down shifts, balance between Ring modulation and Single Sideband Supression.

3. For work you need a quadrature VCO. A Doepfer A110-4 is perfect it produce sine and cosine wave, or a state variable filter is also possible (s/c-sine at LP/HP).

The RMO knob allows continuous shift between ringmoduation (only one multiplier) to single side band suppression. You can create interest sound in-between and enables you to tune exact SSS balance for your signal. The input mixer allows you to insert a digital delay for delayed shifts, so called "Barber-pool phasing".

Modulations VCO: For up or down shifts the phase must be inverted. Doepfers A110-4 produces sine/cosine and shifts phase with LFrq poti. Modulation for LinFrq and XFM for extraordinary shift sounds get possible. Basic desing of A110-4 was intended to use in FS-systems (H. Walmsley).

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