Midnight Requiem of the Masked Rite ( play with https://sonic-pi.net/ )

midnight_requiem_of_the_masked_rite.rb

# Stir the cauldron at 135 beats per minute
use_bpm 135

# Shared sigils - when the light dies, all hearts go silent
set :stop_flag, false
set :master_amp, 1.0     # hidden hand that rules all volumes

# The ward that lets any loop vanish on command
define :check_stop do
  stop if get(:stop_flag)
end

# ---- First veil: a low drone rising from the crypt ----
live_loop :pad do
  check_stop
  with_fx :reverb, mix: 0.6, room: 0.9 do
    synth :dark_ambience, note: :d2,
      sustain: 4, release: 2, amp: 0.7 * get(:master_amp)
  end
  sleep 4
end

# ---- At 4 seconds, the beast awakens below ----
in_thread do
  sleep 4
  live_loop :bass do
    check_stop
    synth :fm, note: [:d1, :d1, :f1, :d1].tick,
      sustain: 0.4, release: 0.6,
      cutoff: 85, amp: 1.5 * get(:master_amp)
    sleep 0.5
  end
end

# ---- At 8 seconds, steel teeth begin to chatter ----
in_thread do
  sleep 8
  live_loop :hats do
    check_stop
    sample :drum_cymbal_closed,
      amp: 0.6 * get(:master_amp) if spread(3, 8).tick
    sleep 0.5
  end
end

# ---- At 12 seconds, the old Amen breaks through the door ----
in_thread do
  sleep 12
  live_loop :break do
    check_stop
    sample :loop_amen, beat_stretch: 4,
      amp: 1.2 * get(:master_amp)
    sleep 4
  end
end

# ---- At 16 seconds, ritual drums speak their pattern of blood ----
in_thread name: :ritual_rhythm do
  sleep 16
  
  hit_pattern = (ring 1, 2, 1, 0)   # one, two, one, silence
  
  live_loop :tribal_kick do
    check_stop
    hits = hit_pattern.tick         # how many strikes this bar
    
    if hits > 0
      gap = 2.0 / hits              # forces each bar to last two beats
      hits.times do
        sample :drum_tom_lo_soft,
          rate: 0.8,
          amp: 0.5 * get(:master_amp),
          finish: 0.4
        sleep gap
      end
    else
      sleep 2                       # the circle rests
    end
  end
end

# ---- At 24 seconds, dissonant vapours coil around the hall ----
in_thread name: :atmospheric do
  sleep 24
  live_loop :dissonance_pad do
    check_stop
    use_synth :hollow
    play chord(:cs3, :minor7).choose,
      release: 8, amp: 0.4 * get(:master_amp)
    sleep 8
  end
end

# ---- At 32 seconds, the masked choir chants in reverse tongues ----
in_thread name: :melody_in_d do
  sleep 32
  forward_phrase = (ring :d4, :f4, :e4, :d4, :c4, :d4, :e4, :f4)
  
  live_loop :masked_ball_rev, sync: :pad do
    check_stop
    
    with_fx :reverb, mix: 0.8, room: 0.9 do
      with_fx :echo, phase: 1, mix: 0.5 do
        use_synth :dark_ambience
        
        # the chant walks backward, one heartbeat at a time
        play forward_phrase.reverse.tick,
          sustain: 0.6, release: 0.4,
          amp: 0.9 * get(:master_amp)
      end
    end
    
    sleep 1
  end
end

# ---- At 90 seconds the light fades, the doors slam shut ----
in_thread name: :cinematic_fade do
  sleep 90                     # length of mortal patience
  
  fade_secs  = 16              # descent into silence
  steps      = 64              # small turns of the screw
  step_sleep = fade_secs.to_f / steps
  
  steps.times do
    current_amp = get(:master_amp)
    set :master_amp, [current_amp - (1.0 / steps), 0].max
    sleep step_sleep
  end
  
  set :stop_flag, true         # all sounds obey the hush
end