The filter section is found at the bottom right Atom's interface, and helps shape the overall tone of your sound by removing certain frequencies:
To activate the filter click the grey light located on the top right of the Filter section. When the light is pink it means the Filter section is turned on.
The "Cutoff," control determines where specifically the filter begins cutting frequencies. For example, a low pass filter with a cutoff of about 636 Hz means that frequencies above 636 Hz will begin to be cut out of the sound.
To raise the cutoff frequency where this starts happening you can turn the Cutoff knob to the right.
For High Pass filters this process is reversed: the higher the "Cutoff," the smaller the amount of frequencies will be passed through the filter. Thus to make a High Pass filter do less work you'll want to to turn the "Cutoff," knob to the left instead of the right.
The "Res," knob controls the resonance of the filter. This means that it will create an EQ boost near the cutoff frequency, which can create some interesting results when used to a sound. Turning this knob to the right will make this EQ boost more pronounced. A "Res," of 0 has no resonant boost applied to the sound at all.
The "Drive," control adds a bit of saturation to the filter. Turning the knob beyond 0 will begin to add more and more saturation, while leaving it at 0 will apply no saturation whatsoever.
Atom comes with 4 filter types to choose: LP12, HP12, LP24, and HP24. By clicking on any of these four filter options the overall filter Atom uses will be selected:
LP stands for Low Pass, which means only lower frequencies are passed through the filter and higher frequencies are removed. HP stands for High Pass, which means only higher frequencies are passed through the filter and lower frequencies are removed.
LP12 is a less aggressive low pass filter (meaning more high frequencies still come through into the sound), while LP24 is our most aggressive low pass filter. This means that most of the high frequencies will be drastically cut out from the sound.
HP12 is a less aggressive high pass filter (meaning more low frequencies still come through into the sound), while HP24 is our most aggressive filter and removes most low frequencies entirely. This means that most of the low frequencies will be drastically cut out from the sound.