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Pascal Herczog
2004-01-05, 05:03
I recently ran MP3gain and was horified to see a large number of MP3's showing as 'clipping' based on their current gain settings. Now, nearly all have been made using EAC and lame 3.9x from my CD's, so I am surprised that these should end up clipping. Does anyone know if this is common, or have I overlooked something in Exact Audio Copy?

Then it made me think that when I get a squeezebox (slimp3 only today), I'd also like to ensure the WAV volume levels are normalised. Currently I have a SBLive card for recording vinyl, and the s/w (wavestudio) is pretty good but the one thing it does not do is tell you the peak and RMS levels of the wav file as a dB number. So although it does let you change the levels, I've no idea by how much to change them, and I also need to balance left and right channels.

So the second question is, is there a freebie program that will let me analyse WAV volume levels? (preferably free since the SB Wavestudio does everything else I need!).

Thanks,
Pascal.

Nicolas Guillemain
2004-01-05, 06:41
Le 05/01/2004 à 13:03:19, Pascal Herczog écrivait :

> I recently ran MP3gain and was horified to see a large number of MP3's
> showing as 'clipping' based on their current gain settings. Now,
> nearly all have been made using EAC and lame 3.9x from my CD's, so I am
> surprised that these should end up clipping. Does anyone know if this
> is common, or have I overlooked something in Exact Audio Copy?

This has been discussed in a recent thread on this list. Clipping
during playback is indeed common, especially with modern, heavily
compressed music (once again, there is *no* actual clipping in the MP3
frames, clipping only occurs during playback because of rounding errors
inherent to MP3 decoding -- that's what mp3Gain looks for when it marks
the file as "clipped").

Just use mp3Gain to "remove" clipping and you'll be fine. I found the
default settings (album gain, 89 dB) to work fine for me, but you might
want to crank it up a few dBs to preserve dynamic range as long as the
number of "clipped" files is acceptable. It's all reversible anyway, so
if you have a lot of music to process, you'll probably want to
experiment with a few albums first.

Be seeing you,
Nicolas
--
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