normailizing without distorion?

[iThinkYouBrokeIt]

What's the best way to normalize audio so that it sounds much louder than the source material, without causing it to sound distorted?

I've been trying to use RMS normalizing at 0.20, and it gets to the volume level that's acceptable, but i seem to lose quite a bit on sound quality. how do i increase volume while avoiding this? And are there any free programs that can do this for me???

[redwudz]

You didn't say what you are using to normalize. For freeware, try Audacity. If your audio has already been 'overprocessed', then normalizing may cause distortion.

[olyteddy]

If it's MP3, MP3Gain.

[iThinkYouBrokeIt]

I'm using GoldWave and using RMS normalizing method @ 0.20. it's an older version because the newest version of GoldWave doesnt have RMS for some reason.

The source file is mp3 (which i convert to wav) audio extracted from an AVI video file.

I need to use some form of volume boost because i intend to convert to mp4 to play on my psp. and without using any volume boost, the movie sounds horribly low and i can barely hear anything, especially if im somewhere public like on the bus...

[iThinkYouBrokeIt]

Sooooo is there any way i could boost the volume while keeping its quality?

[aedipuss]

try getting rid of the mp3 conversion step. do mp2 to wav to mp4. do your manipulations on the wav. every resampling step loses some quality.

[iThinkYouBrokeIt]

the source is mp3. why would i do mp2?

i dont resample. the source has 48khz. i do volume boost via goldwave and keep it at 48khz, and my result file (the mp4 video) has 48khz audio.

All i need is to make it noticeably louder so that when i watch in public, on a bus or something, i can hear it. And I would like to keep good quality with it. There's got to be a way of doing this...

EDIT: I'm also doing a series of videos from dvds, AC3 audio, which really need volume boosting as well...

[manono]

If the source is MP3, then why didn't you take olyteddy's advice from earlier in the thread to boost the volume using MP3Gain? Be careful. It'll boost it as much as you want, and it's easy to get clipping (distortion), but if you do it right, it'll hand you back max normalized volume without clipping.

http://mp3gain.sourceforge.net/

[iThinkYouBrokeIt]

I tried mp3gain earlier, and it was... weird.

and yeah i would very much like to avoid clipping while boosting the volume. what's the best way to do this with a wav file? im trying audacity and im not sure if it will be able to do what i need. (or perhaps its user error)

and mp3gain seems like it might be able to work for me, but is there any kind of setting to auto-avoid clipping?

[manono]

Well, it has a pretty good help file included with it. Open the MP3, click on "Track Analysis", and after it's done, if it is too soft, it'll tell you how much you can raise the volume from the volume level you have in the "Target 'Normal' Volume" box. Adjust that number (89 is the default) until "Track Gain" is 0 and hit the "Track Gain" button near the top to make the changes. If that didn't make any sense, like I said, the Help file is good, and has pictures.

Sorry but I don't know anything about Audacity.

[iThinkYouBrokeIt]

I used MP3 gain to boost volume while avoiding clipping.
The clipping avoidance is great, it avoided it completely and the sound quality is really good. However, it is still not loud enough. Is it at all possible to make it as loud as i want while still avoiding clipping???

[lordsmurf]

Open it in SoundForge, normalize it higher, save it as MP3 again. In perspective, you've spend 10 days asking about something that would have taken me maybe 10 minutes, using SF.

[manono]

There are probably some loud passages in there, guns firing or some loud music, which is limiting the volume for the rest of the audio. Sometimes you can boost it a bit and not notice the clipping, even though it's there. Otherwise you'll have to do as lordsmurf says and convert it to WAV audio, open it in a WAV Editor, and knock the tops off of the big waveforms, normalize again and convert back to MP3.

[iThinkYouBrokeIt]

There are probably some loud passages in there, guns firing or some loud music, which is limiting the volume for the rest of the audio. Sometimes you can boost it a bit and not notice the clipping, even though it's there. Otherwise you'll have to do as lordsmurf says and convert it to WAV audio, open it in a WAV Editor, and knock the tops off of the big waveforms, normalize again and convert back to MP3.

yeah, im a bit of a n00b when it comes to audio...

i'll try what you said and see how it goes

[iThinkYouBrokeIt]

There are probably some loud passages in there, guns firing or some loud music, which is limiting the volume for the rest of the audio. Sometimes you can boost it a bit and not notice the clipping, even though it's there. Otherwise you'll have to do as lordsmurf says and convert it to WAV audio, open it in a WAV Editor, and knock the tops off of the big waveforms, normalize again and convert back to MP3.

how do i knock the tops off the wave forms?

EDIT: sorry for the double post. i meant to delete the other one, but cant figure out how. ive never had to delete a post on this forum...

[manono]

Hi-

I don't know anything about lordsmurf's SoundForge, but they're all pretty much the same, I'd guess. So, is it true that you have just a few places where the sound gets loud? I use CoolEdit Pro, I isolate around the real high waveforms one at a time, and cut the amplitude by 3 or 6 decibals, or whatever it takes.

[mattso]

Or try a slight 2:1 compression over the whole thing.

[iThinkYouBrokeIt]

I would prefer methods that don't require payware. or at least ones that dont require $300 payware.

i'll see if i can try the 2:1 compression and see how that goes. thanks for the suggestions, guys...

[unclebud]

MP3Gain is MP3 normalizing freeware. You can do whole folders of MP3's at once. It's adjustable and seems to work pretty well. With this you don't transcode out of MP3 and back. Quality preserved.

[iThinkYouBrokeIt]

Or try a slight 2:1 compression over the whole thing.

The 2:1 compression seems to not really do anything but make the entire thing half as loud as it already is. which defeats the purpose of doing a volume boost on it...