Clicks in between data and exporting problems

[CharlieSteal]

So i'm working on creating a looping engine sound. I have the exact sound I want, but at the end of the sound it puts a very distinct click or pop. The sound is about 3 second long. When I duplicate it it also leaves pops in between each duplicate, but raising the bass seems to solve that problem. I need to just get rid of the popping noise so I can duplicate it however many times without having to raise bass again. Any cut I make adds a click in its place if I'm cutting off the end of the sound. When set to loop audacity restarts it instantly which is the exact speed I want but when i export to mp3 it slows down considerable and puts a gap of silence before it. The manual talked about click when plotting the spectrum, but I am already using the recommended settings. How can I fix the popping and exporting problems? Any help is appreciated. Thanks in advance

[kozikowski]

<<<When set to loop audacity restarts it instantly which is the exact speed I want but when i export to mp3 it slows down considerable and puts a gap of silence before it.>>>

Two problems I can see. Where did you get the original sound clip from? Audacity will occasionally edit a sound clip that it doesn't really understand. Sometimes you're OK until you try to export and then you get crazy results.

The interstitial pops are probably caused by mismatched blue waves when you edit. It's also possible you have a damaged sound file and it's creating battery or DC problems. See: where did you get that sound file from?

Koz

[kozikowski]

Magnify the blue waves and try to pick edit points that preserve the up and down rhythm and cadence.

If I joined the first two waves -- eliminate the gap, I would get a significant pop since neither the direction nor the level matched. The second two both go through the mid point and they're going in the same direction -- down. If I joined those two waves I wouldn't get any pop there at all. Koz

[steve]

when i export to mp3 it slows down considerable and puts a gap of silence before it.

Looping MP3s always causes clicks due to a limitation of the MP3 format that means that there will always be a short bit of silence before the start of the sound. This is not a fault in Audacity or in Lame but a limitation of the format itself.

For gapless loops you need to use a format that does not have this limitation such as WAV, AIFF, FLAC, OGG ...

For click free loops the conditions that Koz wrote about also apply.