DFX is a digital audio processor and mp3/streaming audio enhancer. It is a plug-in available for many popular programs like WinAMP and RealOne (once known as RealPlayer). DFX uses professional audio algorithms and 32-bit floating point precision. You can adjust the tone as little or as much as you want though the use of five settings, which can be set anywhere from one to ten, or turned off entirely.

Harmonic Fidelity Restoration ("Fidelity")

This setting carefully regenerates the high-frequency harmonics which are usually lost in the mp3 encoding process, especially on the lower bitrates. After listening to a song with Fidelity Restoration on, it may sound bland and muffled without it.

Ambience, Stereo Imaging ("Ambience")

The stereo depth and ambience of an mp3 can be lost in the encoding process; this setting restores these properties, and can add some reverb to the sound. I've noticed it's easy to overuse this setting, and set to nine or ten, it will completely destroy the sound; it will sound like there's a mushroom cloud forming a few miles away.

3D Surround

This setting adds amazing depth and fullness to the sound, making it sound large and grand on traditional two-speaker systems and even laptop speakers. It makes it sound even better on Dolby 5.1 or similar surround sound systems.

Dynamic Boost

Most PC speakers have limited headroom, meaning they can only get so loud before distorting. This setting processes the audio and increases the percieved loudness of the sound without altering the percieved sonic range, meaning that certain frequency ranges won't distort or boost differently. This will supposedly enable a PC speaker system to play up to twice as loud. Great for people whose New Years Eve resolutions look like: Lose half my hearing in one ear by June!


This compensates for low frequency ranges and improves the bass performance of a sound system. Similar to Fidelity, this works by carefully regenerating the low-frequency harmonics of the sound. This increaces the percieved loudness of the bass without exceeding the physical limits of the speakers - something which is very easy to do on most PC speakers.

Other options include:

  • Headphones Optimization
  • This processes the audio in such a way that the sound seems to originate at some point in front of you, rather than within your head. This is more pleasant, and eliminates the irritation of having Pantera playing "inside your head."

  • Skinning
  • Everybody has skins/themes now; why not let DFX have some fun?

  • 38 Presets
  • Optimized presets for everything from '80s Metal to Classical.

  • Compatibility
  • Compatible with WinAMP, MUSICMATCH, Windows Media Player, RealOne, Sonique, and J.River Media Jukebox.

It should be noted that DFX takes up a lot of CPU power. I'm running an 800mhz machine with half a gig of RAM, and DFX for me uses anywhere from 14% to 40% of my CPU time. For most people with relatively recent machines, this shouldn't be too detrimental, but you wouldn't want to leave it on while compiling the latest version of the Mozilla source.

Finally, possibly the worst thing about it is the price! This plugin is a good forty dollars, which is an awful lot for a shareware plugin. If you're an audiophile, you'll probably find it worthwhile, but the casual KaZaA user will scoff and return to messing around with the Equalizer.

There is a trial period, but it has an extremely annoying nag screen which hangs around for a few seconds whenever you start the program up, the 3D Surround setting cannot be used, Headphone optimization is disabled, and sliders will only move up to five.

The above is factual, the following is my opinion.

First and foremost, I've noticed that some mp3s actually sound best without any fancy 32-bit Digital Audio Processing. Nevertheless, most mp3s, and even ogg files, sound millions of times better than usual with DFX. I think it's mostly the Fidelity that does it; this is my favorite enhancement. Everything sounds sharp, punchy and beautiful with Fidelity - it's better than drugs. At the other end of the spectrum is Ambience. I usually leave this one off; I find it almost annoying and feel that it modifies the sound too much, even on the lower settings. 3D Surround I used to leave off, but I think I'm starting to like it; it does indeed make the sound "bigger and deeper," mostly on a medium-to-high setting (around six).

Dynamic Boost is a pretty good option, I'll generally leave that at four or five, because it seems to have an effect similar to that of 3D Stereo. Hyperbass I keep very high - eight or nine - because I'm a bass freak. Maybe that's why I play bass. It does a good job of increasing the percieved bass volume without making my speakers cry. These are the JBL speakers which came with the Compaq I received back in 1996 or so.

All in all, give it a listen and decide for yourself. You can find their web site at www.fxsound.com, where you can download the trial version - if you dare. As I mentioned above, the trial version is crippled nagware.