increase volume

I'm trying to increase volume in a mix. The recorded audio imported from a portable recorder is a little low. I've max the EDIT Adjust Volume Envelopes and it sounds good at full volume. Once I export the mix it gets low again. I've added audio files to a multimedia app (Soundslides) and the volume drops significantly. Once on the web is hard to hear unless you have external speakers cranked. How do I increase volume in Soundtrack 1.5 audio tracks?