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-------------------------------------------------------------------------------
PHASEX Signal Routing:
-------------------------------------------------------------------------------


+-----+      +-----+
|Osc-1|      |Osc-2|      (!) lfos, inputs, envelopes, velocity, midi note,
+-----\      /-----+          or tempo based frequency.
   ^   \    /   ^
  (!)   \  /   (!)        (*) inputs, envelopes, velocity, midi note,
         ||                   or temp based frequency.
+-----+  ||  +-----+
|Osc-3|  ||  |Osc-4|      (#) velocity.
+-----\  ||  /-----+
   ^   \----/   ^
  (!)  |Mix/|  (!)    +------+  +---------+  +------+  +-----+
       |/Mod|-------->|Filter|->|Amplifier|->|Chorus|->|Delay|
       /----\         +------+  +---------+  +------+  +-----+
+-----/  ||  \-----+    ^ ^         ^  ^                    |
|LFO-4|--||->|LFO-3|----+ |         |  |                    v
+-----+  ||  +-----+      |         |  |                 +------+
   ^     ||     ^        (#)       (#) |                 |Output|
  (*)   /  \   (*)                     |                 +------+
       /    \                          |
+-----/      \-----+                   |
|LFO-2|----->|LFO-1|-------------------+
+-----+      +-----+
   ^            ^
  (*)          (*)


  Please note that the signal diagram shown above is a simplified
  overview of the synth architecture as a whole.  Signal inputs marked
  with (!), (*), (#) add a level of flexibility beyond what is shown.

-------------------------------------------------------------------------------

The oscillators are inter-modulated in the modulator sections, where
each oscillator serves as the carrier with independently routable
modulators for amplitude, frequency, and phase offset modulations.

The LFOs serve mostly as additional modulators to facilitate basic
time-based gating, sweep effects, cyclical effects.  But they can do
more.

Anything is possible in the modulator sections.  4-op/4-lfo AM/FM/PM.
This is where a patch gets its texture, timbre, and harmonic content
beyond that of the original waveforms used.  With PM, this is also
where a patch gets it's initial spatial quality within the stereo
field.  Play with the modulations one at a time.  Sometimes combining
all three modulation types is a bit much, especially AM.  Sometimes
the FM needs to be fine-tuned to really bring out the right harmonics.

After being modulated, oscillators are then mixed onto a single stereo
mix bus.  Depending on the 'Mix Mod' setting, an oscillator either
Mixes down onto the mix bus, Amplitude Modulates the mix bus, detaches
from the mix bus to allow it to become a Modulator only, or turns Off
completely.

The filter carves out frequency space (and can add some of it back in
at higher quantities with resonance).  The phasex filter uses the
standard filter bands: LowPass (keep frequencies below the cutoff),
HighPass (keep frequencies above the cutoff), BandPass (keep
frequencies surrounding the cutoff, and BandStop modes (scoop
frequencies centered at the cutoff).  The combo modes just stack two
of these filter bands together, both with their center frequency tied
to the filter cutoff.  Filter cutoff can modulated by velocity or an
lfo.  It is also modulated by the filter envelope.

The amplifier gives the patch it's dynamics based on note-on/note-off
messages, velocity data, and an ADSR envelope.  This is what shapes
the amplitude, or volume, into distinct "notes".  Panning and stereo
width are handled in the amplifier before the signal is routed through
the effects.

-------------------------------------------------------------------------------