Class: Wavify::DSP::Effects::Phaser

Inherits:
EffectBase show all
Defined in:
lib/wavify/dsp/effects/phaser.rb,
sig/effects.rbs

Overview

Modulated all-pass phase shifting effect.

Constant Summary collapse

MAX_STAGES = 
32
TAIL_AMPLITUDE = 
1.0e-6
MAX_ALLPASS_COEFFICIENT = 
0.9
REFERENCE_SAMPLE_RATE = 
44_100.0

Constants inherited from EffectBase

EffectBase::TAIL_CHUNK_FRAMES

Instance Method Summary collapse

Methods inherited from EffectBase

#apply, #build_runtime, #flush, #latency, #lookahead, #process, #reset

Constructor Details

#initialize(rate: 0.5, depth: 0.7, feedback: 0.2, mix: 0.5, stages: 4) ⇒ Phaser

Returns a new instance of Phaser.

Parameters:

  • rate: (Numeric) (defaults to: 0.5)
  • depth: (Numeric) (defaults to: 0.7)
  • feedback: (Numeric) (defaults to: 0.2)
  • mix: (Numeric) (defaults to: 0.5)
  • stages: (Integer) (defaults to: 4) 


13
14
15
16
17
18
19
20
21
 
# File 'lib/wavify/dsp/effects/phaser.rb', line 13

def initialize(rate: 0.5, depth: 0.7, feedback: 0.2, mix: 0.5, stages: 4)
  super()
  @rate = validate_positive!(rate, :rate)
  @depth = validate_unit!(depth, :depth)
  @feedback = validate_feedback!(feedback)
  @mix = validate_unit!(mix, :mix)
  @stages = validate_stages!(stages)
  reset
end

Instance Method Details

#process_sample(sample, channel:, sample_rate:) ⇒ Object 



23
24
25
26
27
28
29
30
31
 
# File 'lib/wavify/dsp/effects/phaser.rb', line 23

def process_sample(sample, channel:, sample_rate:)
  dry = sample.to_f
  coefficient = modulated_coefficient(channel)
  wet = process_allpass_chain(dry + (@feedback_samples.fetch(channel) * @feedback), channel, coefficient)
  @feedback_samples[channel] = wet
  @lfo.next_value if channel == (@runtime_channels - 1)

  (dry * (1.0 - @mix)) + (wet * @mix)
end

#tail_duration ⇒ Object 



33
34
35
36
37
38
39
 
# File 'lib/wavify/dsp/effects/phaser.rb', line 33

def tail_duration
  return 0.0 if @mix.zero?

  pole = [MAX_ALLPASS_COEFFICIENT, @feedback.abs].max
  decay_samples = (Math.log(TAIL_AMPLITUDE) / Math.log(pole)).ceil
  (@stages * decay_samples) / REFERENCE_SAMPLE_RATE
end