Gadgets: Better digital sound on the go

As audiophiles go mobile and take music with them on their travels, device makers are trying to keep up by offering headphones and portable speakers to enhance the sound. Unfortunately, the music stored on a portable device is compressed, making it sound flat and dull.

Leave it to a DJ to come up with a way to enrich that experience.

Val Kolton, a professional DJ and founder of V-Moda, a maker of high-end headphones, and his team have developed the Vamp, a precision headphone amplifier that works with the iPhone 4 and 4S to give digital music a more intense, deep sound.

The Vamp, which is available at V-Moda's website and Amazon.com for $650, bypasses the iPhone's hardware and uses its own high-fidelity processor to reverse the analog-to-digital conversion, allowing listeners to hear their music in a richer form. It features two audio processing modes, a pure mode and an equalizer mode that provides a spatial 3-D sound.

The Vamp is lightweight, at less than 5 ounces. The back of the case is made of sturdy brushed metal, while shock-absorbing silicon grips the iPhone securely in place.

Music listeners can simultaneously use the iPhone to perform other tasks, and sounds like text message alerts and ring tones are audible through the headphones.

Jittergram is a nifty free iPhone app that helps you make and share simple stop-motion animations, like those that you see in "Wallace and Gromit" cartoons or the 1980s "Clash of the Titans" movie. It's pretty easy to use, but not so easy that it couldn't benefit from some instructions.

Jittergram has two settings. In one, you make a digital lenticular 3-D image -- that's the fancy name for those pictures under a plastic lens that makes the image shift when you tilt it. It's great for animated GIFs. In the other, you make stop-motion animations.

The trick to getting a good image is to pick one element of the photo to be stationary, while other parts shift. When you snap your first picture, you will see a ghostly image of that shot. Use that transparent image to line up the next shot, with some object remaining in the same place, and the other objects in a different place.

Click the second shot and the animated result will appear. You can now send it by e-mail, post it to Twitter or save it.