Gadgets: Audio-enhancement apps

Thanks to a new generation of so-called audio enhancement apps, your music's sound quality doesn't have to entirely depend on your smartphone.

LouderLogic, free on iOS, functions just like the iPhone's Music app and looks much like any other music-playing app, except for a large green button labeled "ALX" that turns on its "Audio Level eXtension" technology.

ALX makes tones sound much warmer and vocals seem brighter. It gives movies theater-quality sound, even on headphones. The ALX button automatically delivers this effect, but users can manually adjust the sound quality with audio equalizer controls when the phone is turned sideways.

Obviously, ALX works better with certain tracks. The app's design is a little garish, and there are some pop-up ads in the free edition. But an ad-free version is available for $2.

On Android, an equivalent app is DFX Music Player Enhancer, which is also free. The app calls itself the first to bring "professional audio quality" to Android devices and says that its goal is to restore some of the "lost natural depth" of music recordings.

The DFX Player makes the music sound livelier and the bass notes warmer than through a typical Android music app. You can also precisely adjust audio levels and choose settings to suit different types of music. On the downside, the app's interface is a bit clunky and not as polished or easy to use as it could be.

Headquake, a free iOS app, might be the most impressive. Headquake uses a special-effects engine called Sonic Emotion to give sounds a 3-D quality. You read that right — it tries to manipulate a standard stereo music track so the music sounds as if it is coming from different parts of the room.

For the right track, the effect is startling. And Headquake is free, so there's nothing to be lost by giving it a whirl.