It isn’t a good idea to publish podcast as they were recorded, without any mastering work. On the other hand, dealing with many files, and performing the same tasks many times can be frustrating. In this situation one should definitely use gnormalize.

gnormalize works in Linux and it requires GTK+ libraries version 2.6.x. Other dependencies include:
gtk2-perl (version >= 1.040), wavegain, cdparanoia. Encoders are also needed, if you want to convert files: lame, faac, oggenc, mppenc, mac and flac. Decoders are: oggdec, mppdec and faad.

gnormalize can rip audio cd; encode audio data; convert audio format between MP3, MP4, MPC, APE, FLAC and OGG; and change the encoding and ID3 tag properties of final normalized files. The application is a front-end to wavegain, an audio converter, encoder, ripper, meta data (tag) editor and audio cd player.

Supported formats: MP3, MP4 (or M4A or ACC), MPC (or MPP or MP+), OGG, APE and FLAC. gnormalize decodes the MP3, MP4, MPC (or MPP - MusePack), APE (Monkey’s Audio), FLAC and Vorbis OGG files to wave, then normalizes the wave to a targeted volume level and re-encodes it. As a result you receive normalized (louder) WAV / MP3 / OGG files, ready to be burned on CD or published in the internet. This tool is mandatory if you want to post your own podcast, and do it quickly.