Is it better to normalize* volume in the compressed domain (MP3) or in the uncompressed (WAV) domain? By better I mean the most accurate with the lowest chance of clipping in the resulting MP3 file.

Can someone recommend a normalizing tool for WAV files? Also can someone point me to a definitive guide to using MP3gain? I see conflicting information on the net about how it works and how to use it.

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*By normalize I mean an intelligent normalize like MP3gain does.

Just rip to your favorite lossless codec, then use foobar2000 to ReplayGain your files and then convert to your lossy codec of choice (e.g. MP3). No loss takes place in this process.
Welcome to HA btw^^

Thanks for the info. And the welcome. Now I just need to figure out foobar2000.

Note that while in theory it is better to adjust the gain before lossy compression, in practice the difference should be inaudible under any but the most extreme circumstances.

In case you don't mind the normalization to be permanent, apply it on the WAV. But be sure to use the same gain for the whole album/compilation, or else you might get a surprise during some track changes.

But AFAIK the most comfortable way is to apply it on the compressed audio either using replaygain (audio data is not changed, so playback needs replaygain support) or mp3gain (audio data is changed, can be reversed tho if you don't delete the tags and it's compatible with all mp3 playback systems).

I should say that my preference would be for the normalization to be applied to the data so it will work on all players, i.e., no replaygain support required on playback since I use several different players. Any recommendations for a tool to use to normalize wave files? Is wavgain still an option? How does EAC's normalize function work? My apologies if this is common knowledge, I've been out of the digital audio world for a while.

WaveGain isn't lossless, ReplayGain in foobar2000 is. Of course the loss of WaveGain isn't great, it isn't even audible, but why do the lossy method when there is a lossless option?
1) Rip to a lossless codec with tags, like FLAC (so the ReplayGain info can be stored in the tags)
2) Open the files in foobar2000, right-click on them and select ReplayGain -> Scan Selection as albums (by tags)
3) You can convert them now to e.g. MP3 (or any other lossy codec, that is the cool thing), with right-click on the files and "Convert". Don't forget to tick "ReplayGain processing", so the adjusted volume is encoded within the file.

For the different ReplayGain modes, like album and track, consider the Mp3gain help file. That would also cover your prior question to Mp3gain.

If you have already encoded MP3s and would like them to be normalized the best option would be Mp3gain. I recommend the way with foobar2000 for freshly ripped CDs, because it's more accurate.

EDIT: Hope my post isn't too confusing ^^

i use "MP3 Tools"
<http://www.hydrogenaudio.org/forums/index.php?showtopic=38313>
and "Omni Encoder"
<http://www.hydrogenaudio.org/forums/index.php?showtopic=46639>

If you really worry about clipping in mp3, then consider this: it is possible that a wav file adjusted by wavgain without clipping will produce mp3 that will have clipping. This is due to how mp3 encoder changes the waveform of the signal.
Then you would have to apply mp3gain on top of wavgain only to get rid of this extra clipping. (Another question is whether such clipping is actually audible or not. One has to listen.)


Another thing: wavgain can adjust loudness precisely, whereas mp3gain only approximately (in steps of 1.5dB). However, given the approximate nature of replaygain approach, this difference may be negligible.


And finally, wavgain is relatively slow (must re-write whole wav file). mp3gain is fast (only small modifications of mp3 file).

/edit: Of course, applying replaygain to lossless file such as FLAC is also fast (only tag is modified).
The other two points above (about wavgain) still hold also for FLAC replaygain.

One should also mention that the psy model ATH setting assumes that you are not going to make dramatic changes in volume level after encodng. This argues for making gain adjustments before encoding or, better yet, during encoding.

kdo, my limited experience would agree with you. I can listen to the normalized wav file and it sounds fine but after encoding I hear the distortion. Its nice to get a second opinion.

OK, this is slightly off topic, but maybe what I assumed was clipping is something else and I'm hearing some kind of MP3 encoding artifact. It sounds like a 'scratching' or sometimes a popping sound. I've tried encoding at different bitrates but I get the sound at the same place.

If this is present in the MP3 but not in the original then the thing to try is to reduce the gain on the MP3 and listen to it. If it goes away then it was clipping, otherwise it is an artifact.

Sorry to bring an old topic up, but it basically fits what I'm also trying to do. I've ripped several tracks to FLAC, and want to make sure that they are all approximately the same volume, before I burn them as a compilation CD (not an MP3 data disc). The volume doesn't have to be exactly the same for each one - just as long as I don't have to change the volume on my stereo to listen to a different track!

I'm new to Foobar2000 (version 0.9.4.5), so please help me out. As I said, I have the tracks in FLAC format. As per the instructions above, I right-clicked on the whole selection, and selected ReplayGain -> Scan Selection as albums (by tags). When Foobar2000 completes that, the status of each track is Success, and I'm asked to Update File Tags, which I do.

It's at this point that I get stuck. Going by the above quote, I need to convert the tracks to WAV, with the "ReplayGain processing" box ticked. So I select all the tracks, right-click, Convert, Convert To, WAV, and have the ReplayGain processing box ticked. However, the ReplayGain processing says "None", meaning, I guess, that no normalizing is to be done.

Where am I going wrong?

Thanks!

MP3Gain is very good solution as well.

I know that my question is in the wrong forum, but I thought it was worth replying here because aside from the conversion to MP3, my query seems to be the same.

Can MP3Gain normalize FLAC files? I want to keep this lossless, as I'm burning a compilation CD (not an MP3 CD).

If you mean that the displayed value is "None" after you have clicked the "..." button in the converter window you need to open the drop-down list and select your preferred option.

In your case I would use "Source Mode: track" and "Processing: apply gain and prevent clipping according the peak".

That seems to have done the trick! Thanks!