Difference between revisions of "Removing Artifacts"

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(Update DC offset div.)
(Repairing Popping Vocals: created a link to the new "DC offset" page - and removed the note re Windows h/w DC removal)
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Should you still have popping or percussive vocals, here's how to repair them, though it will never be as perfect as a good original recording:
 
Should you still have popping or percussive vocals, here's how to repair them, though it will never be as perfect as a good original recording:
  
'''1)''' Make sure the recording's DC offset is zeroed. (This in itself will eliminate one possible cause of clicks generated by subsequent edits and silences and should be done before you do any editing). Do this by selecting the whole track and choosing the {{menu|Normalize}} effect. In the resulting box make sure you've only selected "Remove DC offset".
+
'''1)''' Make sure the recording's [[DC offset]] is zeroed. (This in itself will eliminate one possible cause of clicks generated by subsequent edits and silences and should be done before you do any editing). Do this by selecting the whole track and choosing the {{menu|Normalize}} effect. In the resulting box make sure you've only selected "Remove DC offset".
  
 
'''2)''' Zoom in on the percussive sound. They're easy to pick up. They look like a big single waveform just before the rest of the sound.
 
'''2)''' Zoom in on the percussive sound. They're easy to pick up. They look like a big single waveform just before the rest of the sound.
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'''4)''' Since these percussive sounds are mostly very low in frequency, some users have reported great success using the 'high pass' effect instead of the 'fade in' effect as suggested in step ''3)'', above. Note that the 'high pass' effect can be repeated multiple times on the same selection. This approach has an additional advantage of not interfering with or reducing the level of higher frequency sounds, an advantage when the vocal percussive sound was recorded along with other instruments or sounds.
 
'''4)''' Since these percussive sounds are mostly very low in frequency, some users have reported great success using the 'high pass' effect instead of the 'fade in' effect as suggested in step ''3)'', above. Note that the 'high pass' effect can be repeated multiple times on the same selection. This approach has an additional advantage of not interfering with or reducing the level of higher frequency sounds, an advantage when the vocal percussive sound was recorded along with other instruments or sounds.
{{note|Newer Windows PCs may have a [[Proposal DC Management|DC offset]] cancellation feature when recording from the built-in sound inputs. To check or enable:
 
#Right-click over the speaker icon in the {{menu|System Tray > Recording Devices}}, or click {{menu|Start > Control Panel > Hardware and Sound > Sound}}, then the "Recording" tab
 
#Right-click over empty space, show disabled and disconnected devices, then right-click over each device and enable it
 
#Right-click or select each device, choose "Properties" then look in the "Enhancements" tab
 
#If there is no "Enhancements" tab, look in the sound device's own control panel in "Hardware and Sound".}}
 
 
{{CategoryTips}}
 
{{CategoryTips}}

Revision as of 16:04, 31 October 2012

Related information:

  • See Noise Removal for tips on removing clicks and pops from vinyl recordings.


Repairing Popping Vocals

Manually fixing 'breath sounds' on a vocal recording can take an inordinate amount of time - so if possible avoid them in the first place. A 'pop-shield' between speaker and microphone can help, and can be made cheaply. Here's an easily made pop filter  using a small embroidery hoop and a stocking, it's credited to Jake Ludington.


Should you still have popping or percussive vocals, here's how to repair them, though it will never be as perfect as a good original recording:

1) Make sure the recording's DC offset is zeroed. (This in itself will eliminate one possible cause of clicks generated by subsequent edits and silences and should be done before you do any editing). Do this by selecting the whole track and choosing the Normalize effect. In the resulting box make sure you've only selected "Remove DC offset".

2) Zoom in on the percussive sound. They're easy to pick up. They look like a big single waveform just before the rest of the sound.

3) Select this waveform and then choose the fade in effect. This will soften the percussive and hopefully solve your problem.

4) Since these percussive sounds are mostly very low in frequency, some users have reported great success using the 'high pass' effect instead of the 'fade in' effect as suggested in step 3), above. Note that the 'high pass' effect can be repeated multiple times on the same selection. This approach has an additional advantage of not interfering with or reducing the level of higher frequency sounds, an advantage when the vocal percussive sound was recorded along with other instruments or sounds.