Audacity Forum

rjh-median.ny Thanks for that My median filter is actually only suited for this specific kind of impulse-noise. You will maybe never encounter it in real life. I've occasionally come across corrupted digital files which had noise like that. ... it is a common filter for data, where edges should be ...

Here's another corrupted file that you can try to clean: short clicks before after.mp3 (189.18 KiB) That's miraculous , where can I get a median filter ? I tried cleaning your example with my technique, there was some improvement but nothing in comparison to your "after". As your frequent...

In effect it is acting as an amplitude dependent low pass filter. The noises this technique removes seem to include the entire sound spectrum, rather than a specific frequency range, see the third take of the flac below which is the original crackly record minus the de-clicked version, (i.e. the no...

It's putting thumps in the show. After has "fist smacking a pillow" sounds that Before does not have. Do you have a killer sound system or good headphones? Earbuds. Pressing them in my ear'oles for a better bass I can now hear the thumps. I was concentrating on the bit from 1-to-3 seconds...

I had an idea for click-reduction via differentiation then limiting then integration. 1. differentiate the waveform ... (multichan-expand #'slope s) this produces a waveform with big spikes where there were clicks. 2. Then use a limiter to reduce these big spikes, then integrate ... (multichan-expan...

Lassar wrote:I have figured out how to get the envelope curves to work.
But when I press play, I don't hear any change.

A large change in envelope is required before there is a glaring change in volume

I tried to record my lecture So it's not your lecture. It's the lecture you attended. Maybe just the sound recording device attended ;) Whilst the mp3 posted has a sample-rate of 22050Hz the recording only has content up to 4KHz consistent with a sample-rate of only 8000Hz. Next time use a higher s...

... move from low pass filtered sound to high pass filtered sound or vice-versa ... see ... http://forum.audacityteam.org/viewtopic.php?f=39&t=74039 For sweep with "resonance" see ... www.kvraudio.com/product/classic_auto_filter_by_kjaerhus_audio a link to "Classic Auto-Filter.dl...

What sort of AM does Trebor's code produce? Is it double sideband suppressed carrier? From the spectrogram of the before-after mp3 above , it's "double sideband suppressed carrier" on the "after" the spectrogram is reflected about the carrier frequency (1KHz in this case) ... Sp...

Yes, it can be done quite easily using the "Nyquist Prompt" effect. Select the track that has the really low sound, then open the Nyquist Prompt, then copy/paste this code into the text box of the Nyquist Prompt: (defun AM (sig) (mult 0.5 (sum 1 sig)(hzosc 2000))) (multichan-expand #'am s...