Recordings came out too loud

[tractorguy]

I recorded some MP3's from an old album. During the recording process (View fit vertically) I turned up the volume because it seemed to low. It looked OK when I saved it, but now when I re-open it I can see that it is maxed out. There seems to be a difference in the "view" between recording and playing. Is there a way to "turn the volume down" on those recordings?

[bgravato]

It shouldn't be any difference in view between recording and playback. I'm not very sure if I understand what you mean.

To change the volume of the recording you can use the amplify effect (default is to amplify to 0dB, which is max volume before clipping, but you can set it to negative numbers). Nonetheless if you got clipping the damage is irreversable... and the only solution is to record it again at lower volume.

When recording you might aim at lower peak volume. -6dB (in dB scale, or 0.5 in 0-1 linear scale) is a conservative value... You can them max it out with the amplify effect.

Also be aware that mp3 is a lossy format... that means that mp3 adds some distortion to the show, due to its compression algorithm. That damage is also irreversable, so if you save as mp3 only and then open it again later you won't get what you had before. For that you'll have to export it in a lossless format such as WAV or FLAC.

There have been reports that sometimes exporting a show in mp3 that is maxed out to 0dB will result in some clipping after the mp3 compression is done... Some people prefer to amplify to -0.3dB instead of 0dB to avoid that (some suggest more conservative values between -2dB and -1dB peak).

You can clearly identify clipping in audacity by red lines in the wavform (instead of the normal blue).

[tractorguy]

Problem Solved. I deleted all the "loud" files and started experimenting with the 'gain' during the recording process..........it's not dynamic, i.e. when I move the slider to the right to increase the gain it doesn't effect the 'display" but it sure does effect the actual recording. If I export the file, and then re-open it, there is a big difference! I don't know how to take a screen shot, save it and then attach it to this message, but I did take photos of the monitor with a camera, if you would like to see them. Anyway, the 'input slider' I found in the Sound Preferences/input tab, is dynamic, and working with that I am now able to change the level of the recordings. Is the gain slider supposed to be dynamic? I am working with a very scratchy 60's something MONO recording so MP3 is quite good enough.

[steve]

when I move the slider to the right to increase the gain it doesn't effect the 'display" but it sure does effect the actual recording. If I export the file, and then re-open it, there is a big difference!

Yes, that is how it is supposed to work.
The track Gain slider increases the playback volume without altering the actual track data, which means that you can fiddle with this adjustment as many times as you like without changing the actual track data in any way. When the track is "mixed down" (either using the "Mix and Render" command in the Tracks menu, or Exporting), the Gain (playback volume level) is taken into account - in other words, during mixing the gain level is applied to the data.

This means that if you increase the track gain level, you will need to keep an eye on the playback meter to ensure that you do not "over cook" it and cause distortion.
A good way to check that you have not increased the gain level too much is, before you Export, select all tracks in the project (Ctrl+A) and use "Mix and Render" from the Tracks menu. This will mix down all of the tracks, and apply the gain levels, while you are still in the Audacity project. If you have "Show Clipping" enabled (View menu), any clipped audio will be marked with red vertical lines, providing you with the opportunity to Undo (Ctrl+Z) and adjust the Gain levels down a bit.