The Ultrabeat noise generator lets you create a wide range of percussive sounds and sound elements. The noise generator has its own filter, which functions independently of the main Ultrabeat filter, although the noise generator filter can also be used on the overall sound.
Technically, a noise signal contains all tonal frequencies, at a roughly equal volume level. As all frequencies in the spectrum are audible, it makes it difficult for human beings to hear any tonality (pitch) in a noise signal. Despite this, or as a direct result of it, noise is an indispensable ingredient when creating drum sounds.
On/Off button: Turn the noise generator on or off. When programming a drum sound, you can turn the individual sound sources on or off. You can also listen to, or remove, individual components of the sound separately in this way.
Filter Type buttons: Switch the noise generator integrated filter between lowpass, highpass, and bandpass filter types.
LP (lowpass): This filter type allows frequencies that fall below the cutoff frequency to pass. The filter slope is fixed at 12 dB/octave.
HP (highpass): This filter type allows frequencies above the cutoff frequency to pass. The filter slope is fixed at 12 dB/octave.
BP (bandpass): The frequency band directly surrounding the center frequency (determined with the Cutoff knob) is allowed to pass. All other frequencies are cut. The Resonance parameter controls the width of the frequency band. The bandpass filter is a two-pole filter with a slope of 6 dB/octave on each side of the center frequency of the band.
byp (bypass): Disables the integrated filter.
Cutoff and Resonance knobs: Rotate to set the cutoff/center frequency and resonance/bandwidth behavior of the noise generator integrated filter.
The Cut knob defines the point in the frequency spectrum where the signal is boosted or cut. Depending on the selected filter type, you can make a sound darker (LP), thinner (HP), or more nasal (BP) by adjusting the Cut value. Cutoff can be modulated by sources in the mod and via pop-up menus.
Increasing resonance boosts frequencies that surround the cutoff frequency. Values range from 0 (no increase) to self-oscillation of the filter at high resonance values. Self-oscillation is typical of analog filter circuits. It occurs when the filter feeds back into itself and begins to oscillate at its natural frequency when high resonance values are used.
Dirt knob: Set higher values to alter the white noise signal, making it more grainy. The Dirt parameter is particularly effective at high resonance values. Dirt can be modulated by sources in the mod and via pop-up menus.
Volume knob: Rotate to set the output level of the noise generator. Volume can be modulated by sources in the mod and via pop-up menus.
Signal Flow button: Use to route the noise generator signal through the main Ultrabeat filter or directly to the EQ (Output) section. When turned on, the button is lit and an arrow indicates the direction of the signal flow.
Note: The Signal Flow button has no effect on the independent filter within the noise generator. The independent filter is deactivated with the “byp” button. It is therefore possible to filter the noise generator signal twice. In some instances you may want the noise generator signal to bypass the main filter, thus freeing the main filter for other drum sound processing duties.