The Low Pass Cutoff limits the high frequencies that are played. It lets the low frequencies ‘pass’ or ‘get through.’ This is similar to turning down the treble knob on a stereo.
Low Pass Cutoff: The cutoff represents a frequency value is between 0% and 100%. The default is 100% and means you hear all frequencies in the sound. 0% equates to a very low cut off frequency and you would not hear any sound.
Low Pass Resonance: As this value increase, the overtones near the cutoff frequency are boosted. The result is that the cutoff frequency is much louder than the rest of the audio being filtered.
IMPORTANT: The Low Pass Cutoff works hand in hand with the Low Pass Resonance. The Low Pass Resonance setting will not be audible if you haven’t adjusted the Low Pass Cutoff!
Tips:
q To use the resonant filter creatively, try a resonant filter sweep. To do this, set the Resonance envelope at 200 and create a Cutoff envelope that rises and falls slowly. Since the resonant value is relatively high (200), as the cutoff goes up and down you should distinctly hear the "resonant peak" follow the cutoff, with its characteristic sound. For example, the famous wah-wah pedals used by guitarists, makes use of resonant filter sweeps back-n-forth, with the cutoff controlled by the foot pedal.
q If the resonant setting is cranked all the way up to 256, the filter goes into a state called "self-oscillation" and produces a ringing-whistling tone. ATTENTION: this can be very loud and overwhelming, so please watch your audio levels as it can be dangerous for your ears and your speakers!!
q Using resonant filter sweeps on synthesizer melody lines can make some very musically compelling timbre and tone changes, to signal a transition, a buildup or a bridge.
* The cutoff % is a mapped logarithmically from 200 Hz to ˝ sample rate.