View Full Version : Normalise volume?
Sep 27, 2009, 01:40 PM
Is there a way to "normalise" the volume of a play list?
I got a play list of music from various sources and the volume are very different, some are very loud some are not. I want to burn them on to a CD. Does iTunes provide a function that makes all tracks to have similar volume so when I play the CD in my car I don't go deaf when the louder songs comes up?
Sep 27, 2009, 02:08 PM
Sep 28, 2009, 11:02 AM
Thanks for your suggestion I have tried it out. While it may not be a bad program I think my collection may be a little too tricky for software to figure it out, I'll adjust it manually but thanks anyway!!
Sep 28, 2009, 12:47 PM
Well ivolume doesnt actually normalize songs to full volume (as in raise the higest peak in a song to 0dB). It analyzes frequenies and makes songs "sound" the same volume. It knows if a song has more bass than midrange, that song needs to be pumped up more than a song with more midrage even thogh both songs have the same peak amplitudes. Our ears hear midrage better then bass, so to make the one with more bass "sound" the same volume, it pumps that one up more. I think what your looking for is a dynamics compressor, which makes all soft and loud parts of music or any sound file, about the same amplitude all around. Its what radio sations do to keep levels the same all around.
Oct 8, 2009, 11:07 PM
lostless- I think he's looking for normalization not dynamic range compression as he states he has music from different sources that are of different base volumes.
Does not the "Sound check" feature if iTunes do exactly what you want? It analyzes each track and normalizes each such that they should play with the same loudness for each track.
iVolume is a little more sophisticated iteration of the concept, using the popular ReplayGain algorithm developed to analyze tracks and compensate for loudness. iVolume (and iTunes' sound check) does not alter the audio content of the music files, nor would you want it to. That would be altering and likely destroying data which should be avoided (kind of like saving a JPEG over and over, or re-compressing an already compressed MP3 file).
What it does do, is modify a tag in the header (similar to the title, artist, etc. information embedded in the header) telling the player how loudly or softly to adjust the playback by for that track. A smart burning program, I suppose, would respect this normalization value in the burn process as well.
The nice thing about iVolume thatI believe iTunes does not do, is that it can normalize songs an album at a time. Meaning it will normalize the audio level of all albums to be the same, but keep the relative differences between tracks within an album the same. This preserves the artist's intent that maybe some songs should have been louder than others on an album. iTunes sound check just normalizes all tracks irrespective of album.