- Sig In Level (VCF1/2/3)
- The RS360 has one audio signal input, individual LEVEL controls determine how much of the input signal is fed to each of the filters.
- Frequency (VCF1/2/3)
- You may control the cut-off frequencies of each of the filters individually using the FREQUENCY controls provided. When a given Frequency knob is in its fully anticlockwise position, the cut-off frequency it controls is approximately 30Hz. As you rotate that knob clockwise, cut-off frequency increases until, it its fully clockwise position, it exceeds 15kHz.
- Resonance (VCF1/2/3)
- Each filter offers resonance, or â€˜Qâ€™, that you control using its RESONANCE knob. In the fully anticlockwise position, Q is approximately zero, and there is no emphasis of the signal at cut-off frequency. As you rotate the knob clockwise, Q increases, whereupon every mode of that filter will accentuate the harmonics that lie close to the cut-off frequency. Increasing Q further, the filters will exhibit ringing, and will severely colour the signals passed through them. If you continue to increase the resonance beyond a certain point, the filter will begin to oscillate, and each mode will produce a sine wave at the cutoff frequency determined by the various controls. This oscillation is produced by all four audio outputs.
The exact nature of the wave varies from mode to mode, and you can use these differences to create tonal variations when using the RS360 as an oscillator bank.
- CV-In Vary Depth
- controls how much the CV-In Vary input influences the cut-off frequency.
- Master Frequency
- modifies the cut-off frequencies for all three filters simultaneously. This knob and its associated cv input control all three filter cut-off frequencies simultaneously within the range âˆžV/oct to approximately 0.4V/Oct. The former of these makes the input invariant to incoming CVs, while the latter makes it oversensitive compared to the CV-IN 1V/OCT input.
- VCF1 CV-In 1V/Oct
VCF2 CV-In 1V/Oct
VCF3 CV-In 1V/Oct
- You may also control a given cut-off frequency using the associated CV-IN 1V/OCT input. If you apply a CV conforming to the 1V/Oct standard, cut-off frequency will track the CV in exactly the same way as a standard VCO. If the CV is supplied from a keyboard then, in common parlance, the filter tracks the keyboard at 100% and, with the resonance at maximum, you can â€˜playâ€™ the filter as if it were a conventional oscillator.
- VCF1 CV-In 1V/Oct
- CV-In Vary
- modifies the cut-off frequencies for all three filters simultaneously. This socket and its associated DEPTH knob control all three filter cut-off frequencies simultaneously within the range âˆžV/oct to approximately 0.4V/Oct. The former of these makes the input invariant to incoming CVs, while the latter makes it oversensitive compared to the CV-IN 1V/OCT input.
- audio input, accepts signals in the range Â±10V.
- Low Output
- low-pass filter output
- High Output
- high-pass filter output
- Notch Output
- notch filter output
- Band Output
- band-pass filter output
Just as the precise positions and shapes of the formants in a human voice allow you to identify the identity of the speaker as well as the vowel sound spoken, formants make the timbres of acoustic instruments consistent and recognisable from one instrument to the next. It therefore follows that recreating formants is a big step forward for synthesising many types of sounds.
Normally, formant synthesis requires at least three formant filters per sound with appropriate CVs for each. The RS360 provides all of this in a single module 24HP module. However, the RS360 is more than just a formant filter. All three filters produce the four common filter characteristics: low-pass, high-pass, notch and band-pass, with summed outputs that offer the low-pass outputs of all three filters, the high-pass outputs of all three, and so on.
You can also use the RS360 as an effects unit. If you route different outputs (say, band-pass and notch) to two panned channels, you can produces stereo effects reminiscent of the flangers and phasers used in early multi-keyboards. Furthermore, you can use the three self-oscillating filters as multiple audio signal sources, or create unusual waveforms from the three â€˜partials'.