DFX Audio Enhancer is an audio processor which uses various techniques to improve the sound quality of media players, websites, and any other program on your PC.
A simple console offers sliders for Fidelity ("regenerates... missing high frequency harmonics"), Ambience ("regenerates... ambience and stereo depth"), HyperBass ("regenerates... low frequency harmonics, thus increasing the perceived bass, but without exceeding the speaker's physical limits") and Dynamic Boost (processes "the audio to increase the perceived loudness of the audio without altering the perceived dynamic range").
Each slider represents values from 0 to 10, but the free version only runs up to 5. If you drag it further, an alert dialog pops up to say "no, can't do that", which is annoying if you keep doing it by accident.
There's also a fifth "3D Surround" slider which doesn't work at all unless you upgrade.
DFX Audio Enhancer offers a 10-band equalizer (or 9 + "Dynamic Bass"). You can't use most of the presets in this version, but it's possible to save your own.
Please note, DFX Audio Enhancer will by default install other programs along with its own code. To avoid this, pay attention during setup and select "Skip", "Decline" or whatever other "no thanks" options you see, as they come up.
DFX Audio Enhancer made some difference to our test PCs audio, but not much more than you'd expect from an equalizer. We wouldn't want to use the free version, either - too many restrictions and nag screens - and overall the full build seems a little expensive. Audio processing is very subjective so try it anyway, if you're interested, but don't expect too much.