Hi, i ripped plenty of cds with EAC and foobar. I got a new hard drive and loaded EAC once again, i ripped a cd a new one and the cd's volume sounded low compared to my other rips. I have to raise the volume in foobar when playing that album and then lower it on other albums.

Question is, are all CD's have there own VOLUME? Some (loud, some low)? Or is it because i didn't rip the cd with my speakers on?<-- or does that even matter?

You have actually stumbled upon why things like ReplayGain were created in the first place. Some CDs are mastered louder than others or from your point of view one of yours is much quieter than the others. This is normal and since CD is a digital medium provided your rip was accurate you're going to have exactly what was on the CD. And even if it wasn't a secure pops or clicks are the kinds of artifacts associated with a bad rip.

Speakers have nothing to do with ripping; they're just at the end of the playback chain.

Hey DreamTactix291, thanks for the information. Appreciated. I was wondering will this replay gain hurt the quality of the song files? Like if it's Monkey's Audio and is ripped to keep the quality. But using a replaygain on the Album will lose quality? Or does it not affect it in that way?

Sorry, i'm unclear about that part.

ReplayGain adjusts volume. It does not degrade quality.

Well there are two ways of applying ReplayGain to material. You can either add it via tags by using a ReplayGain scanner in either commandline form or built into another application like foobar2000. The disadvantage to this approach is that the player much be ReplayGain tag aware. Alternatively, if your files are mp3s you can choose to apply the gain to the files directly via MP3Gain. This modifies the global gain field of each frame in the file but it is reversible as the application writes an undo tag in the file as well.

ReplayGain doesn't reduce quality although due to the excessively loud levels that many commerical CDs are mastered today the vast majority of your collection is going to get a reduction in playback volume. This is normal, and after all of your files have ReplayGain information they'll all play back at the same volume so no shifting of the volume dial.

There is also TrackGain and AlbumGain. TrackGain makes sure all of the tracks in your collection play back at the same volume regardless of the original differences of songs from the same album. AlbumGain scans the tracks in an album and adjusts the volume of an entire album as one unit so an excessively quiet piano track won't get elevated to just as loud as a metal track on the same disc. With tag based ReplayGain you can freely switch between whichever one is used if you scan for AlbumGain as both TrackGain and AlbumGain values are stored. The MP3Gain method however forces you to pick one or the other.

There are most likely others here who can probably explain this a lot more eloquently than I, but I think I managed to somewhat explain the process.

Just to confirm what seems obvious to me is true, you could also AlbumGain a whole album with MP3Gain, and then apply TrackGain to selected tracks if you wanted to make, say, a compilation for playing in the car?

Michael

There's no reason why you couldn't. It just wouldn't be as automated and if you wanted to keep a copy that is AlbumGained and a copy that is TrackGained you would actually have to have two copies.

What about losing resolution? People here told me that when not playing back at 100% volume, you get less bits; a 16bit source can result in, say 10bit playback, thus "losing quality".

Theoretically, there's some loss, but in practical terms, the loss is negligible and inaudible.

Reducing from 16-bit to 10-bit is about 36 dB reduction (very quiet and far more than ReplayGain will ever do). Even the most extreme ReplayGain reduction on today's maximised singles is little more than 12 dB (a loss of 2-bits resolution). Thanks to dither and the way the ear works, the perceivable dynamic range of 16-bit audio is in the region of 120 dB. Even knocking 12 dB off that is still a range equivalent to the threshold of hearing all the way up to operating a chainsaw at full speed without ear defenders (typically around 110 to 113 dB will be shown on the warning label on a chainsaw), so practically, the loss caused by Replaygain's maximum attenuation is negligible, even if you have an exceptionally quiet listening environment.

I'm not sure I can connect bit-depth with volume.

I can convert a 16-bit sample to an 8-bit one and it sounds just as loud. But quality is lower. I can play it back on 8-bit equipment (so there's no upscaling from 8 to 16 bits) and again, same volume but lower quality.

As an extreme example, convert a 16-bit sample into a 2-bit one. Still loud but probably just a series of random clicks.

I can have a range of 120db even with 8 bit; the quantization increases (volume differences are "steppy") therefore it's possible.

Unless there's something I'm missing

Let's say you have a 16 bit file. You replaygain this file with 6~12 dB volume reduction, and you get 14~15 bit resolution on playback.

But in case your noise floor covers up the lower bits, you'll never notice the difference. The noise floor is bound to be higher than the volume of the lost resolution, so no need to worry.