Volume Normalisation?

[JethroUK]

I've converted a lot of CD's to mp3 and the volumes are all over the place

I'm assuming this is what normalising takes care of, but is there any additional loss in quality?

Do you use it?

[xoas]

Re: Volume Normalisation?

There are 3 strategies for dealing with the situation of having tracks with different volume levels.

You can live with it and try to adjust your expectations.

You can apply automatic settings to adjust the volume on playback. dAP has a feature known as Auto Volume Boost which will do this. There is also a feature called ReplayGain which achieves the same effect by storing volume information in the file tag. In either case, the volume adjustment is only applied on playback and only through players that support these features (Auto Volume Boost only works with dAP, ReplayGain is apparently supported by a greater variety of players and programs). Currently, dMC does not support ReplayGain but I undestand that dMC R12 will eventually support ReplayGain. Both of these methods leave the original audio qualities of the file intact.

The other approach is to standardize volume levels of tracks through Volume Normalization. In dMC, this is achieved through the Volume Normalization and Volume Quieten DSP effects. The first boosts the volume of quiet tracks or of quiet sections withing a track. It will leave loud sections relatively untouched. Volume Quieten lowers the volume of loud sections and/or loud tracks. It will leave quiet sections relatively untouched. Volume Quieten will not remove clipping from an audio file if it is already there. Either or both strategies will reduce the dynamic range of the original audio tracks. In addition, if you apply Volume Normalization to existing giles you are reconverting them which, if you are using a lossy format like mp3, will result in some loss of audio quality. On the other hand, this difference will probably not be audible to most listeners. Still, it would be better to apply volume normalization when you first rip/convert to a lossy format.

Volume Normalization can also produce distortion of audio files. Set too high, you can create clipping and distortion. Adaptive normalization inexpertly used can result in distorted volume levels within a track. If you stick with Simple Normalization set no higher than 100%, you should be fine.

Since I use dAP for nearly all my computer-based listening, I prefer to use the dAP Auto Volume Boost feature (although I am looking forward to trying ReplayGain when that becomes supported by dAP). I will use Volume Normalization when burning CD's or mp3 duisks. I would also consider using Volume Normalization when transferring tracks to my portable mp3 player. When I use Volume Normalization, I use Simple Normalization set at 100%. Other users have said they use different levels ranging from maybe 92% to 98%. Much above 100% you do risk introducing clipping. These recommendations are for home users. We have heard that if you were broadcasting, you might need rather lower levels.

Hope this helps.

Best wishes,
Bill