slackbuilds-current/audio/mhwaveedit

mhWaveEdit is a graphical program for editing, playing, and recording
sound files.  It is lightweight, portable, user-friendly, and handles
large files very well. 

The program itself has only simple editing features such as cut'n'paste 
and volume adjustment, but it can also use Ladspa effect plugins and 
the effects provided by the SoX application.  It can also support 
additional file formats besides wav through libsndfile and mp3/ogg 
import and export through lame and oggenc/oggdec. 

lame, jack, and portaudio are optional dependencies.