The Filter is a key component of subtractive synthesis. It’s designed to remove frequencies from a sound, which can enhance its character. Filters typically consist of a cutoff control, which sets the removal of certain frequencies, and a resonance control, which emphasizes the frequency of the cutoff point.
The most common form of filtering is called lowpass, which means that higher frequencies are removed while lower frequencies pass through without being removed. Most vintage synthesizers employed lowpass filtering, but some also included highpass filtering, which removes low frequencies and lets the high frequencies pass through.
Omnisphere includes an exceptionally versatile dual-filtering system, which features two stereo filters per layer that can be routed in series or parallel. There are thirty-two different filter types available, which include lowpass, highpass, bandpass and other specialized varieties. Because Omnisphere’s filters are stereo, they are ideal for dynamic filter panning effects.
The FILTERS section of the LAYER overview features a basic set of filter controls, such as Cutoff, Resonance, Keyboard Tracking and Filter Envelope Depth. The full set of filter controls are available on the FILTER ZOOM view.
FILTER POWER SWITCH
Enables or disables the Filter.
NOTE: Turning the Filter OFF saves CPU power, since every voice played has it’s own dual-filter per Layer.
Omnisphere has a wide variety of customized filter configurations, called presets. The presets represent the settings of Omnisphere’s complex dual stereo filter. Filter presets can be selected, copied, pasted and saved from this menu.
TIP: If you find a Patch that has an interesting custom filter configuration, you can save it into your Preset library to use with your own Patches!
The Presets are categorized into several sub-categories; Bandpass Filters, Highpass Filters, Lowpass Filters and Specialty Filters. For the sake of space, the preset names are abbreviated, but this is what the different abbreviations indicate:
|BPF||Band Pass Filter|
|HPF||High Pass Filter|
|LPF||Low Pass Filter|
|UVI||UVI Filter from Atmosphere®|
|db||Short for Decibel. Names like 12db, 24db, refer to the roll off slope of the filters.|
NOTE: Filter presets are not the same as Filter types. Filter Presets include the Filter types, Gain, routing and offsets. Filter types are covered in the FILTER ZOOM section.
FILTER PRESET MENU
After a Preset has been chosen from the drop-down menu, the name will be displayed in the preset display window:
If the filter types are changed in the Zoom view, then the display will be changed to “Modified” until the Filter settings are saved as a preset or another preset is selected.
NOTE: Filter presets do not recall CUTOFF, RES, KEY and ENV settings. This is the most accurate way to audition the different Filter Presets within the context of your current Patch.