We've sent a verification link by email
Didn't receive the email? Check your Spam folder, it may have been caught by a filter. If you still don't see it, you can resend the verification email.
Started October 16th, 2008 · 7 replies · Latest reply by nemoDaedalus 15 years, 10 months ago
Hi,
I have been editing some sounds using two free programs: Audaucity and Wavepad.
In one of my sounds there is this pop noise that occurs upon playback. This usually is generated when I edit the sound in some way. Like for example, I might delete a section of a sound, then when I play it back there is this short pop sound right where I edited it.
Might anyone know a way to correct this (a free way preferably).
Thanks!
This happens because the waveforms at the edit are too different from eachother. Note the waveform represents the position of a speaker's conus. Your edit may be trying to force it from all the way forward to all the way back, that's the same as a very high frequency sound. Since that frequency only is played on the edit, it produces a pop.
To avoid this, it is advised to quickly crossfade on the edit. So the two parts actually overlap for 30 to 50 or so milliseconds. The bit before the edit fades out in that time and the bit after the edit fades in.
I have no idea how to accomplish it with Audacity though, I don't understand the program well enough.
I'll try to illustrate anyway though:
this is what you want to edit:
[full track]
incorrect edit, the change from 'l' to 'a' is too large:
[fulack]
Correct edit: the 'l' fades out while the 'a' fades in:
[ful\]
[/ack]
If done properly, this shouldn't be audible.
Usually it is either a clipped waveform or a the DC offset from your soundcard. I downloaded audacity years ago but still have to yet to use it but I am pretty sure it has a DC offset function.
If it's clipped you have the levels too high. I used to go in manually and zoom all the way in and lower that clipped part's volume as low as possible and maybe take off some of the high frequency if possible. I finally used the advanced audio editor by voyetra also known as audio surgeon and clicked the auto pop eliminator and it works amazingly well with way less loss of signal that my old technique.
You could download the trial here:
http://www.turtlebeach.com/products/audiosurgeon/home.aspx
Or try these (I cannot vouch for them but they are free)
http://www.sonicspot.com/antipop/antipop.html
http://www.sonicspot.com/denoise/denoise.html
It looks like audacity has a click remover
http://www.videohelp.com/tools?tool=Audacity
And lastly if you are cutting a waveform and the cycles are not matching up it will create a pop and after reading your post again that is probably what is happening you need to cut sounds on the zero line, neither negative or positive phase.
\ /\ /\ Cut here on the zero line /\ /\
\/ \/ \/ \/ \/
dont try to match up like this:
/\ /\ /\ / /\ /\
\/ \/ \/ / \/
See the break in the waveform?
Think of it like a roller coaster and you cannot hit a brick wall, you need a slope up and down or you will get click or pop. See the previous post about crossfading.
Thanks!
If only forums recognized multiple sapcebar hits and things lined up similar to how they were typed...
A quick way to avoid a click on deleting a section of a waveform, is to use a "snap to zero-crossing" option so that the cuts always occur where the instantaneous amplitude is zero. Then there will not be a sudden change of amplitude where the remainder of the waveform joins.
NoiseCollector
Thanks!If only forums recognized multiple sapcebar hits and things lined up similar to how they were typed...
You can do that using a [code] block. It uses a monospaced font (all characters have the same width) and shows multiple spaces.