Removing thumps and bumps

[dsnillo]

I have tried applying the high pass filter to the thump. It helps, but does not cure it. I will try some more settings...

[dsnillo]

I am trying to minimize a thump caused by a flaw in the vinyl of a record, the best setting I could find was High Pass Filter 250-300 Hz -12 dB, with the shortest possible selection. Repair is no use here, because the artifacts are ~15 msec. long. Larger flaws might require a lower frequency setting.

[steve]

Could you post a short sample in WAV format.
Select about 4 or 5 seconds that includes a thump, then "File > Export Selection".
Attach the file using "Upload attachment" below the message compose box.

[kozikowski]

Yahoo Mail supports up to 25MB. If you make it mono, it might fit. Let us know. I can post it on kozco.com in the original quality so everybody can have a crack at it.

Koz

[dsnillo]

I found that I should first Normalize the track to eliminate DC offset only. (I have been using an old Philips SA 261 to record, it's not perfect.) Then selecting the section with the thump, keeping the selection points where the waveform crosses the zero point. Then apply High Pass Filter. For these thumps 300 Hz and -6 dB worked for me. However, I had to undo, reselect, with slightly different selection points, and apply the filter again, because the filter sometimes didn't match the waveforms at the selection point.

[steve]

I found that I should first Normalize the track to eliminate DC offset only.

Absolutely. You should do this before any processing or editing.

I had to undo, reselect, with slightly different selection points, and apply the filter again, because the filter sometimes didn't match the waveforms at the selection point.

I've posted a new plug-in effect here: http://forum.audacityteam.org/viewtopic ... 07#p204507
This filter effect can automatically crossfade the effect in and out, thus avoiding clicks even if the selection does not start or end at zero crossing points. You will need to make the selection long enough to accommodate the crossfade at the start and end of the selection. A crossfade duration of 20 or 30 milliseconds will probably be about right, but please to experiment to see which works best for you.

This is a brand new plug-in, so any feedback about it would be much appreciated.