Used with BASS_FXGetParameters and BASS_FXSetParameters to retrieve and set the parameters of a phaser effect.
typedef struct { |
Members
| fDryMix | Dry (unaffected) signal mix | [-2....+2] |
| fWetMix | Wet (affected) signal mix | [-2....+2] |
| fFeedback | Output signal to feed back into input | [-1....+1] |
| fRate | Rate of sweep in cycles persecond | [0<...<10] |
| fRange | Sweep range inoctaves | [0<...<10] |
| fFreq | Base frequency of sweep range | [0<..1000] |
| lChannel | The affected channels using BASS_BFX_CHANxxx flags |
Info
Phasers use an internal low frequency oscillator to
automatically move notches in the frequency response up and down the frequency
spectrum. An important difference between phasing and flanging is that phasers
space these notches evenly across the frequency spectrum, while the notches in
flanging and chorus are harmonically (musically) related. You don't hear
the notches as such (because they are the frequencies that are removed).
What you hear is the resulting frequency peaks between these notches. Phasing
works by mixing the original signal with one that is phase shifted over the
frequency spectrum. For example, a four stage phaser signal (such as this) could
be from 0 degrees at 100Hz, shifted to 720 degrees at 5Khz (these extremes are
not quite possible practically, but are near enough to explain the effect). This
is how the term phase shifter comes about. A 4 stage phaser has 2 notches with
bass response, a central peak, and treble response. By using resonance to
enhance the central peak, you can get a sound similar to an automatic wah. Using
a phaser with lots of stages and setting the resonance high can give a sound
similar to flanging, although they are really quite different.
The fDryMix is the volume of input signal & the fWetMix is the volume of delayed signal. The fFeedback sets feedback of phaser. The fRate and fRange control how fast and far the frequency notches move. The fRate is the rate of sweep in cycles per second, fRange is the width of sweep in octaves. And the the fFreq is the base frequency of sweep.
Examples
Dry
Wet
Feedback
Rate
Range
Freq
Phase shift 0.999
0.999
0.0 1.0 4.0 100.0
Slow invert phase shift with feedback
0.999
-0.999
-0.6
0.2
6.0
100.0
Basic phase
0.999
0.999
0.0
1.0
4.3
50.0
Phase w/ FB
0.999
0.999
0.6
1.0
4.0
40.0
Med. phase
0.999
0.999
0.0
1.0
7.0
100.0
Fast phase
0.999
0.999
0.0
1.0
7.0
400.0
Invert w/ invert FB
0.999
-0.999
-0.2
1.0
7.0
200.0
Tremolo Wah
0.999
0.999
0.6
1.0
4.0
60.0
See also
BASS_ChannelSetFX