[LAU] Level Matching

[Roger E]

"You are right. I don't want the dynamics of the tracks changed. I want
the overall 'loudness' of each track to be similar so I don't have to
keep twiddling the volume control."

You need replaygain. Amarok replaygain script can scan and write the tags for albums in the playlist or selected songs in track mode. It's basically just normalization without having to rewrite every file. Of course the player needs to be able to read the replaygain tags too.
Alternatively you could open every file in a wave editor, normalize, then resave. If your file is lossy already (mp3, ogg, m4a etc) you will cause a degradation in quality. Replaygain doesn't change the song data, just adds a tag, so quality is retained.

Roger