Asubboost

Audio Single output Transform

Boost subwoofer frequencies.

FFmpeg filter: asubboost — the official reference.

Add it to a graph. The explicit form works for every filter — bind it to its input and read the result from outputs():

$node   = $audio->addFilter(new Asubboost(…));
$result = $node->outputs()[0];

Shorthand. Single-output filters can skip the node — apply() returns the result stream directly:

$result = $audio->apply(new Asubboost(…));

When to use it

TODO — when this filter shines: what it’s the right tool for, what to reach for instead when it isn’t, and how it composes with neighbouring filters.

How to use it

TODO — prose: how the filter actually works and what its key parameters mean (the explanation FFmpeg’s terse option help omits).

Examples

TODO — runnable PHP, with the equivalent ffmpeg CLI alongside.

Gotchas

TODO

See also

TODO

Parameters

Parameter	Type	Default	Range / values	Description
dry	float	1	0–1	set dry gain
wet	float	1	0–1	set wet gain
boost	float	2	1–12	set max boost
decay	float	0	0–1	set decay
feedback	float	0.9	0–1	set feedback
cutoff	float	100	50–900	set cutoff
slope	float	0.5	0.0001–1	set slope
delay	float	20	1–100	set delay
channels	string	all	—	set channels to filter

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Maps to FFmpeg’s asubboost filter. Verified against ffmpeg n7.1.1.