After cutting/pasting a CLICK/POP is generated on track

[toachieve]

Hello,

After I cut and paste a piece of audio, on playback, a click/pop is heard where the pasted portion meets the original. How do I either prevent this from occurring or remove the click?

[steve]

If you're using the old 1.2.6 version of Audacity you should probably upgrade to Audacity 1.3.13 http://audacityteam.org/download/

The click can probably be removed using the "Repair" effect (probably not available in Audacity 1.2.6, but is in the Effect menu in Audacity 1.3.13).

Better still would be to avoid making the click in the first place. Rather than pasting into the same track, put your edit on a new track and make a little cross-fade from one track to the other. A cross-fade is where one track fades out while the other track fades in - the fade need only be a small fraction of a second to totally eliminate any click.

[kozikowski]

The general instruction for this is to always cut at the zero crossing points. If you blow up (magnify) the blue waves enough, you find that they are just up and down and up and down rhythms. Sound works out best if you cut on one of the places where a wave crosses zero -- in the middle top to bottom. Then, you need to pick a place in the destination where there is another zero crossing -- and the destination wave is going the same way.

That's the official version. In real life, the worst clicks and pops are cause by DC offset.

Cool! I thought I lost my illustration. Here it is:

http://kozco.com/tech/audacity/pix/DCOffset.jpg

As small as it is, that little step will cause a very serious pop in the show.

You can't cure it in post production -- after you already have the pop. You have to "clean" both pieces of music with Normalize > Remove DC Offset before you start editing.

You can do really painful editing where you "fade" between the two pieces of music with the Envelope tool, instead of a simple cut or edit. That's how video editors do sound. They do a very rapid fade between one music and the other -- usually whether you want them to or not.

Koz

[kozikowski]

The click can probably be removed using the "Repair" effect

That's a new one on me.

Better still would be to avoid making the click in the first place.

You can never get back to good with the correction tools. The best you can do is patch up the mistakes so most people don't notice them most of the time.

Koz

[ohthehugemanatee]

kozilkowski - THANK YOU.

I registered an account just to post this message. I've always been frustrated with pops/clicks when copying and pasting, and I knew that a multi-track fade was not the right way to go about it. But I've never had such a good clear explanation of what causes the pop, and what to do about it!

I just did some copying and pasting, and it makes all the difference. DC normalization and copying at the zero crossing is fantastic.

Question: why wouldn't Audacity AUTOMATICALLY find the closest zero crossing for copy/paste boundaries? Or at least have the option to do so. Seems like it would make copy/paste sound a lot better for a lot of people!

[waxcylinder]

... Question: why wouldn't Audacity AUTOMATICALLY find the closest zero crossing for copy/paste boundaries? Or at least have the option to do so. Seems like it would make copy/paste sound a lot better for a lot of people!

You can ask Audacity to do just that for you: make your selection and then use Edit > Find Zero Crossings or use the keyboard shortcut Z

WC

[waxcylinder]

The click can probably be removed using the "Repair" effect

That's a new one on me.

What the repair effect does Koz, is to enable you to select up to 128 samples and it will then interpolate a repaired waveform from the immediately neighbouring waveforms - so it is quite uffective at removing a few clicks here and there.

I used to use that on my LP repairs untiol you steered me in the direction of Brian Davies' excellent ClickRepair software - it was hard work with the manual repairs and easy-peasy with Brian's CR - I am eternally grateful for the recommendation Koz.

WC