erro

[Azarashi]

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[BertKoor]

So you want to throw away all and be left with just the percussion?
Me thinks filters won't help that much. Maybe use transient detectors.
Personally I'd probably recreate the percussion by manually placing the proper notes on the timeline.

[mfb]

I want to filter out all sounds except percussion of a trailer track.

What filtering effects out there are the most efficient?

Not just in this case (as BertKoor pointed out), but quite generally, it is usually difficult to impossible to isolate one instrument from a mixed track by filtering (or any other means). Usually its easier, and will provide cleaner results, to recreate the part. If you're stuck trying to extract an individual instrument from some mixed track, probably some combination of filtering and transient detection (or manually silencing bits where your instrument is not playing) is probably your best bet but expect to spend a lot of time for mediocre results for something like percussion that probably extends across a wide frequency range.