Файл: E-mu E 6400 EOS 4.0 manual.pdf

8 - Preset Edit

Filter Parameters

Filter Parameters

A low pass filter allows only the low frequencies to pass and can be used to simulate many natural sounds since it is common in the physical world for the high frequencies to die away first as the sound decays. Set the frequency of a lowpass filter at maximum if you do not want any filtering action. The various filter types are described at the beginning of this chapter.

Filter Type: 21 filter types are currently implemented. Standard lowpass, bandpass, and highpass filters are included as well as swept parametrics, phasers, flangers, vocal formant filters and programmable morphing filters.

Frequency (Morph): Sets the initial frequency of the filter. In the case of a Morphing filter, this parameter sets the initial position between the two filters.

Resonance (Q, Gain, Resonance, Body Size): High values of Q amplify frequencies near the cutoff or center frequency.

In a swept EQ, Gain controls the amount of boost or cut. In a phaser or flanger, the resonance determines the depth of the effect.

In the vocal filters, Body Size determines the apparent size of the mouth cavity. Gain is a “Note-on” parameter, meaning that it is set at note-on time and cannot be continuously varied during the note.

FILTER TYPES

2-Pole Lowpass

Lowpass filter with 12dB/octave rolloff and Q control.

4-Pole Lowpass

Lowpass filter with 24dB/octave rolloff and Q control.

6-Pole Lowpass

Lowpass filter with 36 dB/octave rolloff and Q control.

2nd Order Highpass

Highpass filter with 12 dB/octave rolloff and Q control.

4th Order Highpass

Highpass filter with 24 dB/octave rolloff and Q control.

2nd Order Bandpass

Bandpass filter with 6 dB/octave rolloff on either side of the passband and Q control.

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8 - Preset Edit

Filter Parameters

Dual EQ Morph

This is a programmable 2-frame Morphing filter with two EQ sections. As the Morph value is increased, the filter interpolates from the low to high settings. The Gain of each section remains constant during the Morph, but can be scaled at note-on time by controlling the Initial Gain parameter. This filter can be used to create your own vocal formant filters.

2EQ + Lowpass Morph

This unusual filter has two EQ sections and a lowpass filter whose Fc is also controlled by the Morph parameter. The Lowpass filter is completely open at a setting of 255. As the Morph value is increased, the filter interpolates from the low to high settings and the lowpass filter allows more high frequencies to pass. The Q of the lowpass filter has an initial setting and can be also modulated at note-on time.

2EQ Morph + Expression

This filter also has two EQ sections and a lowpass filter with independent control over the lowpass filter frequency (Expression). This allows you to use velocity (for example) to control expressive timbre via the lowpass filter, while the Morph parameter is modulated for another effect. As the Morph value is increased, the filter interpolates from the low to high settings.

Peak/Shelf Morph

O Tip: The Morphing filters This 2-frame morphing filter offers independent control over frequency, allow high resonance values shelving and peak for each of the two filter “frames”. The Peak parameter without losing bass power. can also be scaled at note-on time by controlling the Initial Peak parameter.

When the Shelf parameter is negative, the filter will have a low shelving response. When the Shelf parameter is positive, the filter will assume a high shelving response. With Shelf at zero, the filter assumes a peak filter response.

•Note that the two frames of this filter are displayed from left to right unlike the frames of the other morphing filters which are displayed low to high.

v To Set the Filter Parameters:

1.From the Dynamic Processing level of the Preset Editor, select the voice(s) you wish to process using the voice selection screen, then press the Amp/Filt function key (F3).

2.Use the Previous and Next Page buttons to locate the Filter screen.

3.Adjust the Filter parameters as desired. The filter envelope, the filter envelope amount (adjusted in the Cords screen), and the initial filter parameters all interact.

4.Press the Exit button to return to the Preset Definition level of the Preset Editor or press any of the dynamic processing function keys to move to another module.

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8 - Preset Edit

Filter Parameters

Examples of Morphing Filter Response Curves

346 E-MU Systems