Low pass filter
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Please state which version of Windows you are using,
and the exact three-section version number of Audacity from "Help menu > About Audacity".
Audacity 1.2.x and 1.3.x are obsolete and no longer supported. If you still have those versions, please upgrade at https://www.audacityteam.org/download/.
The old forums for those versions are now closed, but you can still read the archives of the 1.2.x and 1.3.x forums.
Low pass filter
Can the low pass filter or high pass filter have a setting higher then 48DB?
Re: Low pass filter
You could apply the filter multiple times.
(This is known as "cascading").
If you apply a 12 dB per octave filter to the same sound twice, it is approximately the same as running a 24 dB per octave filter once, (though the transition from passband to stop band will be more gradual with multiple passes).
(This is known as "cascading").
If you apply a 12 dB per octave filter to the same sound twice, it is approximately the same as running a 24 dB per octave filter once, (though the transition from passband to stop band will be more gradual with multiple passes).
9/10 questions are answered in the FREQUENTLY ASKED QUESTIONS (FAQ)
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kozikowski
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Re: Low pass filter
Scientific application, or actual sound? We are warned that "brick wall" filters tend to not sound very good. That's one of the reasons the Audacity built-in ones don't go any higher than they do.have a setting higher then 48DB?
Natural musical sounds usually have a base tone and a bunch of harmonics and overtones.

That's one single piano note, "G1" (49Hz) way over on the left of the keyboard. All the rest of those tones (measured along the bottom) are what make that piano sound like a piano. Some of those tones buck instead of add. If you take them away, tonal distortion may go up. Even worse, you're taking sound away, but the volume of the note may go up.
Koz
Re: Low pass filter
If you need an extremely steep filter, use "Spectral Delete": https://manual.audacityteam.org/man/spe ... elete.html
9/10 questions are answered in the FREQUENTLY ASKED QUESTIONS (FAQ)
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kozikowski
- Forum Staff
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- Joined: Thu Aug 02, 2007 5:57 pm
- Operating System: macOS 10.13 High Sierra
Re: Low pass filter
It's possible there are a number of other tools to do what you want. For example the mains hum filter and frying mosquito USB microphone errors. Those are careful surgical deletions and sometimes you can't tell they're running.
Those are both "rescue" tools intended to turn an already recorded show with damage into a successful show, or at least one that's not trash. In all cases it's a good idea to fix the recording problem.
Koz
Those are both "rescue" tools intended to turn an already recorded show with damage into a successful show, or at least one that's not trash. In all cases it's a good idea to fix the recording problem.
Koz