[PD] compander-limiter from slop~-help.pd

[Peter P.]

Hi list,

nice weather today, isn't it?

I am trying to understand the [pd compander-limiter] example from
slop~'s help patch because I need a 0dBFS brickwall limiter as
abstraction without externals.

When set to the "no change" parameters, the example will still saturate any
signals hotter than 0dBFS.

I don't understand what the ratio parameter does,
especially its unit and range. It is 100 for dynamic reduction and 200
for expansion in the examples.

Furthermore the threshold parameter is 100 for "expansion" and
"compression", but 60 for "noise gate"...

"Limit" does introduce audible saturation for signals above 0dBFS and I
am wondering which paramters could prevent this. Lowering the speed
parameter to values smaller than 50 improves this a bit. Is speed an
inverse attack time parameter perhaps?

And I can't seem to make sense of the boost parameter.

Any hints are greatly appreciated! Thanks in advance!

Peter