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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Filter Parameters

O Tip: The second filter parameter (resonance, Q, gain, body size, peak, expression) is controlled by the ‘FilRes parameter in the Cords screen.

4th Order Bandpass

Bandpass filter with 12 dB/octave rolloff on either side of the passband and Q control.

Contrary Bandpass

A novel bandpass filter where the frequency peaks and dips cross midway in the frequency range.

Swept EQ, 1-octave

Parametric filter with 24 dB of boost or cut and a one octave bandwidth.

Swept EQ, 2->1-octave

Parametric filter with 24 dB of boost or cut. The bandwidth of the filter is two octaves wide at the low end of the audio spectrum, gradually changing to one octave wide at the upper end of the spectrum.

Swept EQ, 3->1-octave

Parametric filter with 24 dB of boost or cut. The bandwidth of the filter is three octaves wide at the low end of the audio spectrum, gradually changing to one octave wide at the upper end of the spectrum.

Phaser 1

Recreates a comb filter effect typical of phase shifters. Frequency moves position of notches. Resonance varies the depth of the notches.

Phaser 2

Comb filter with slightly different notch spacing than Phaser 1. Frequency moves position of notches. Resonance varies the depth of the notches.

Bat Phaser

Phase shift filter with peaks as well as notches.

Flanger Lite

Contains three notches. Frequency moves frequency and spacing of notches. Resonance increases flanging depth.

Vocal Ah-Ay-Ee

Vowel formant filter which sweeps from “Ah” sound, through “Ay” sound to “Ee” sound at maximum morph. Body size varies the apparent size of mouth cavity.

Vocal Oo-Ah

Vowel formant filter which sweeps from “Oo” sound, through “Oh” sound to “Ah” sound at maximum morph. Body size varies the size of mouth cavity.

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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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Filter Parameters

Examples of Morphing Filter Response Curves

Dual EQ Morph

Amplitude

Section 1

Section 2

Freq:

990Hz

Freq:

9824Hz

Gain:

+17.2

Gain:

+23.6

Frequency

2EQ Morph +Exp

Section 1

Section 2

Amplitude

Gain: +00

Gain: +00

Exp: 110

Exp: 255

Exp:

Exp: 70

35

Frequency

Amplitude

Amplitude

2EQ Morph + Exp

Section 1		Section 2
Freq:	2356Hz	Freq:	8521Hz
Gain:	-24	Gain:	+16

Exp: 127

Frequency

Peak/Shelf Morph

Freq: 9824Hz

Shelf: -46

Peak: 0

Frequency

Amplitude

Peak/Shelf Morph

Freq: 9824Hz

Shelf: +30

Peak: -12

Frequency

Amplitude

Peak/Shelf Morph

Freq: 9824Hz

Shelf: +37

Peak: 0

Frequency

346 E-MU Systems