A simple compression techniques goes like this, and it does wonders to make audio richer…
1. Apply the Compression/Limiter to the clip,
2. open the filter in the viewer
3. Click the preserve volume checkbox
4. Set Threshhold to 0
5. Set ratio to 2
6. loop clip playback
7. slowly lower the threshold until the noise gets louder, but without increase the noise floor/ambient noise.
ian