Auto Gain?

[redlemon]

i have successfully edited out the piece of music i require from a much larger audio file. it plays fine in audacity, but when i export it, the exported file sounds like it's been the victim of some hideous auto gain control.

the quiet sections are hugely amplified, to the extent that background noise is now very noticeable, and there is no dynamic range when in louder sections.

i have tried exporting in WAV, mp3, and ogg. same in all cases.

TIA

[steve]

How are you playing it?

[redlemon]

in VLC and iTunes.

[kozikowski]

<<<i have successfully edited out the piece of music i require from a much larger audio file.>>>

The audio file that you got from where? Audacity is famous for accepting and even editing an audio file when in fact, it has no idea at all what it's doing and may produce a damaged show.

Open up your original file in QuickTime Player and Command-I to get the info panel.

Koz

[redlemon]

iPlayer

[kozikowski]

This isn't a "normal" problem, I'll give it that.

Can we assume you can open up the wav selection export in a freshly started Audacity and it sounds damaged?

It sounds damaged in Quicktime Player and iTunes, right?

What are the Audacity settings in Preferences? 44100, 16-bit, Stereo?

Download Piano2.wav from here...

http://www.kozco.com/tech/soundtests.html

...and do an arbitrary selection and export. Is that damaged, too?

Koz

[redlemon]

i've only ever used audacity for this one job.

it's a piece of music that starts very quietly, then builds to much louder at the end. sounds fine when replayed in audacity, but the dynamics are totally screwed after export in wav, mp3 or ogg when replayed in VLC or iTunes.

maybe i should reload the exported file back into audacity, and look at the db meter to see if the quiet bits look boosted as well as sound it. i'll give it a go when i have a moment and try your piano file as well.

thanks for the help.

[kozikowski]

My vast six-second piano solo will tell us a lot. Your exported segment should sound exactly like the larger sound file it came from.

Koz

[redlemon]

i tried importing/exporting the piano file from audacity:

a very noticeable increase in volume, and possibly an increase of resonance as notes, particularly the last one, decayed.

but certainly not like the file i was originally working with.

[kozikowski]

Wrong answer.

The exported segment should sound exactly the same as the original music in QuickTime Player, iTunes and Audacity.

I'm almost out of ideas.

Go into iTunes > Preferences > Playback. Do you have Sound Check and/or Sound Enhancer turned on?

Koz