output level as reflected in wav form

[kozikowski]

We're going on about this because slightly low, gentle recordings can be easily cleaned up with Amplify or other tools. Overload and clipping are permanent distortions and may kill a show. Stark difference.

While you're Normalizing or Amplifying to 0, please note that in some conditions, converting that show to MP3 will cause overload and clipping. The show in MP3 is not the same show in WAV or AUP. Snugging your show right up against the 0 level is very dangerous and in sometimes hidden ways.

I record off-air shows and I never get much closer than about -4 to -6. Even the serious broadcast compressors up on the hill occasionally let stuff through and I leave room for it.

Koz

[Gale Andrews]

To repeat, View > Show Clipping always shows clipping. It shows every single audio sample that is clipped (not by replacing the blue sample dot, but by adding a red vertical line at that point).

If you are zoomed out, you cannot trust the blue waveform to denote clipping if that clipping is just a few samples (microseconds) of audio and the rest of the audio is not clipped. This is because when you are zoomed out, Audacity cannot display all the samples - at 44100 Hz project rate there are 44100 samples for every second of audio. All Audacity can do if you are zoomed out is to display each pixel at the average amplitude of whatever length of audio that pixel represents. If a pixel represents one second of audio, only one sample out of the 44100 is clipped and the rest of the audio samples peak at 0.5, that pixel will display at 0.5.

If you want another indicator of clipping that you can trust, look at the red hold line to right of the recording meter. That illuminates (and stays illuminated after recording) as soon as four or more consecutive clipped samples are detected. See http://manual.audacityteam.org/o/man/me ... #annotated for more explanation.

If the meter was already bouncing close to 0 when the radio was playing normally, then you should turn the Audacity input slider down a bit, though your waveform extract indicates the level when the radio was playing normally was a little lower than it needed to be. Not much lower, because 0.5 on the waveform is actually -6 dB on the meter. Waxcylinder already explained that to view the waveform in dB as the meter sees it, you have to change the waveform to dB view.


Gale