HydrogenAudio

Hydrogenaudio Forum => General Audio => Topic started by: br0adband on 2003-05-24 08:41:41

Title: Leveling out the audio levels :)
Post by: br0adband on 2003-05-24 08:41:41
Howdy,

I'm in the process of ripping a movie soundtrack (the entire audible portion, not the musical soundtrack) of a movie and it has tons of spots in it where the audio levels get downright low.  I'm curious to know if there are any utilities out there that will level off the entire file to at least bring the more quiet sections up to a respectable threshold.  I don't mean normalization and I'm not sure if WavGain will do what I want either.

I'm doing this because I intend to copy off some movie soundtracks to my MiniDisc so I have something interesting to listen to on that long ride to work on the bus.  I'm sure most of you know what I'm talking about.    Music gets boring after awhile so aside from the audio books I normally listen to I thought I'd take a shot at encoding an entire movie audio soundtrack.

Right now the audio portion is on the hard drive (it's a 1.34GB wav file, 16 bits, 44.1Khz - a rip of The Matrix audible soundtrack, 2 hours 16 mins approximately) and I'm wondering where to go from here.  I have tried to use WavGain on it but didn't notice any appreciable difference so far; maybe I'm just not using WavGain properly.

Any assistance is greatly appreciated and thanks in advance,
br0adband

ps I think what I'm looking for is something like a compressor/delimiter (?!?!) similar to what a radio station uses to limit the dynamics of the audio that they transmit - it's usually a nice even level no matter what song is playing.  Hope this helps. 
Title: Leveling out the audio levels :)
Post by: Nick Jr III on 2003-05-24 09:02:27
Hum... I would recommend you a compressor,
I've ripped DVD soundtracks too, boosted them with this tool and the result was very good !
But take care not to use stupid settings that will loose dynamics...aka: don't overcompress !
And yes, I don't think normalization is a good thing for that.
Title: Leveling out the audio levels :)
Post by: john33 on 2003-05-24 10:12:38
You could try using WaveGain with a Manual Gain adjustment of +6dB, or more depending on the current peak, and also apply the Hard Limiter. This will have the effect of a compressor.
Title: Leveling out the audio levels :)
Post by: mjb111 on 2003-05-24 11:54:45
Cooledit Pro has Dynamics Processing up the wazoo. It's a superb overall audio editor.

Mike
Title: Leveling out the audio levels :)
Post by: ExUser on 2003-05-24 18:35:42
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Music gets boring after awhile so aside from the audio books I normally listen to I thought I'd take a shot at encoding an entire movie audio soundtrack.

Then you aren't listening to the right kind of music.  You need to find your musical niche, and then you shall never emerge from it again.

Technically, though, I don't think a compressor will work for what you want to do. You'll need something that dynamically raises and lowers the gain to keep it at an average.
Title: Leveling out the audio levels :)
Post by: mp3chan on 2003-05-24 18:47:25
what about hard limiter? I think it could be use to raise the sound level without introducing new artifact, and the sound proportion remains the same.
Title: Leveling out the audio levels :)
Post by: br0adband on 2003-05-24 20:26:47
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Then you aren't listening to the right kind of music.  You need to find your musical niche, and then you shall never emerge from it again.


Nah, I've got thousands upon thousands of songs.  There are times when music just doesn't do it.  Sometimes you actually would prefer to learn things (languages, college lectures - I grabbed a lot of Feynman's lectures from the 1960's about physics... fantastic stuff I would never have had the chance to hear unless I did this).

I worked in radio for some time as well so again, music gets boring on occasion.

Personal choice, to each his own I suppose.

Thanks for the info though, I'm working on the file now.
Title: Leveling out the audio levels :)
Post by: grbmusic on 2003-05-24 20:47:20
maybe you want try the RMS normalization of Sound Forge 6.0, I use this tool to raise the sound level of commercial spots for radio stations, I use the -14 dB level. This tool normalize the sound source till 0 dB and then apply dinamic reduction (compresion) and Limiter to reach the -14 RMS level or the level desire. The secret for obtain this in Sound Forge is: scan the wav file for Peak Level and then change to Average RMS power (loudness). You will see than the slice bar (normalize to) change from 0 dB to -12 dB (average RMS), then you can change the value to -14 dBor maybe -16 dB. I don't like to use values uppers to -14 db becouse souns overcompressed and unnatural. In Sound Forge you can use the Wave Hammer tool to, this tool applies a compresor and then a Hard Limiter, but you can not choose the desire RMS level as in Normalization Average Level
Title: Leveling out the audio levels :)
Post by: br0adband on 2003-05-24 21:57:33
Thanks for the info, looking for a demo of SoundForge now but I'll just bet it won't allow me to save. 

There are ways around that though, when I playback the file in SoundForge after it's processed I can use another wav editor to record the data as it's passed off to the soundcard.  Not a perfect copy of course but since I'm dealing with primarily dialogue, the quality is fine.

I don't care about the music, I care about the dialogue and making it easily understandable.
Title: Leveling out the audio levels :)
Post by: grbmusic on 2003-05-24 22:30:49
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I don't care about the music, I care about the dialogue and making it easily understandable.

With Normalize Average RMS in Sound Forge you will can do that
Title: Leveling out the audio levels :)
Post by: ExUser on 2003-05-25 00:14:41
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what about hard limiter? I think it could be use to raise the sound level without introducing new artifact, and the sound proportion remains the same.

Isn't hard limiting equivalent to clipping?
Title: Leveling out the audio levels :)
Post by: LCtheDJ on 2003-05-25 00:31:52
With all the great recommendations here, this may sound just too simple.

You might try playing it in Winamp using the Disk Writer output plugin and the dsp plugin from mpesch3, "Compressor & Wider 1.1 for Winamp" available here: http://www.rz.uni-frankfurt.de/~pesch/ (http://www.rz.uni-frankfurt.de/~pesch/)

At least the tools are free and easy to find.
Title: Leveling out the audio levels :)
Post by: SometimesWarrior on 2003-05-25 10:05:27
When ripping audio from a DVD, it's easy (in fact, standard) to apply some kind of dynamic compression to the audio, using the ripping tools.

At http://www.doom9.org/ (http://www.doom9.org/) you can download a ripper such as DVDDecryptor that will directly rip the AC3 audio data from the DVD. You can then use a converter such as Headac3he that will convert the AC3 audio to Vorbis, MP3, or plain old wave-file. Headac3che will allow you to choose No, Light, Medium, Heavy, or inverse dynamic range compression. Most hardware/software DVD players default to Medium, or somewhere between Light and Medium. PowerDVD allows you to choose between Light, Medium, or Heavy when playing a DVD, so you can experiment in real-time if you have that program.

I'm testing this out now on a DVD from my collection, to make sure I'm giving sound advice.

Edit: just finished the conversion, and it worked just fine. Let me know you want to know the exact procedure I used. It takes very little user input to accomplish, and the whole process took the computer 30 minutes from start to finish.
Title: Leveling out the audio levels :)
Post by: smok3 on 2003-05-25 14:22:21
@SometimesWarrior: that would be a good suggestion imho,
use 'heavy' if you want parts of the soundtrack to be of the similar loudness, like for loud listening enviroments.
(in any case this will be better than any compressor imho)
Title: Leveling out the audio levels :)
Post by: mp3chan on 2003-05-25 23:11:16
Quote
Quote
what about hard limiter? I think it could be use to raise the sound level without introducing new artifact, and the sound proportion remains the same.

Isn't hard limiting equivalent to clipping?

Nope. It's not the same. Hardlimiting is similar to compressor but it's attack and release is very fast. When it finds a signal is clipping, the attack (in this case lowering the sound level) will only apply to this clipping signal so that the clipping won't occur, and release the attack after 20 ms or so. So you won't hear any distortion, hopefully.