Why can mp3 go above 1.0 peak when other formats cant? |
  |
Why can mp3 go above 1.0 peak when other formats cant? |
 Aug 5 2010, 13:05
Post
#1
|
|
|
Group: Members Posts: 113 Joined: 22-January 08 Member No.: 50696  |
i have noticed many of the mp3s i download from archive.org (Creative Commons) go above the 1.0 Track Peak according Replay Gain, however i have not been able to notice this in other formats. when rendering audio losslessly it clips, why/is mp3 an exception?
|
 |
 
|
|
Aug 5 2010, 13:16
Post
#2
|
|
 Group: Developer Posts: 2986 Joined: 2-December 07 Member No.: 49183 |
AAC, Vorbis, Musepack, AC3 can also have replaygain_track_peak > 1.0
|
|
|
|
|
Aug 5 2010, 16:36
Post
#3
|
|
 Group: Members Posts: 4135 Joined: 2-September 02 Member No.: 3264 |
QUOTE (CoyoteSmith @ Aug 5 2010, 08:05)  i have noticed many of the mp3s i download from archive.org (Creative Commons) go above the 1.0 Track Peak according Replay Gain, however i have not been able to notice this in other formats. when rendering audio losslessly it clips, why/is mp3 an exception? All lossy formats do this if they're peak normalized. |
|
|
|
|
Aug 5 2010, 17:37
Post
#4
|
|
 ReplayGain developer Group: Developer Posts: 4588 Joined: 5-November 01 From: Yorkshire, UK Member No.: 409 |
QUOTE (saratoga @ Aug 5 2010, 16:36) All lossy formats do this if they're peak normalized. i.e. if the original was peak normalised, then when you encode it lossy-ly, some of the peaks get pushed higher.Most lossy formats are floating point internally, so they can cause values to be reconstructed that are far higher than the defined 0dB FS. Cheers, David. |
|
|
|
|
Aug 6 2010, 00:36
Post
#5
|
|
|
Group: Members Posts: 2038 Joined: 31-August 05 Member No.: 24222 |
Uncompressed wav can do the same thing -- much higher peak that 0dB coming out the DAC if the DAC has adequate headroom.
|
|
|
|
|
|
Lo-Fi Version | Time is now: 24th May 2013 - 06:14 |
