Digital Audio’s Final Frontier

Mini but mighty Class D amps are forging audio’s future

12 min read
Photos of prototype single-channel amplifier and six-channel production unit by Nicholas Eveleigh
Believe it or not, the tiny prototype single-channel amplifier on the left puts out 150 W. The six-channel production unit on the right delivers 50 W per channel. Both Class D amps are by Philips.
Photos: Nicholas Eveleigh

Digital technology continues its march from media like CDs and DVDs toward your audio speakers. Today, amplifiers based on digital principles are already having a profound effect on equipment efficiency and size. They are also beginning to set the standard for sound quality.

An old idea, the Class D amplifier has taken on new life as equipment manufacturers and consumers redefine the musical experience to be as likely to occur in a car, on a personal stereo, or on an airplane as in a living room. For most consumers today, portability and style outweigh other factors in the choice of new audio gear.

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Engineers Are Working on a Solar Microgrid To Outlast Lunar Nights

Future lunar bases will need power for mining and astronaut survival

4 min read
A rendering of a lunar base. In the foreground are rows of solar panels and behind them are two astronauts standing in front of a glass dome with plants inside.
P. Carril/ESA

The next time humans land on the moon on the moon, they intend to stay awhile. For the Artemis program program, NASA and its collaborators want to build a sustained presence on the moon, which includes setting up a base at which astronauts can live and work.

One of the crucial elements for a functioning lunar base is a power supply. Sandia National Laboratories, a research and development lab that specializes in building microgrids for military bases, is teaming up with NASA to design one that will work on the moon.

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Trilobite-Inspired Camera Boasts Huge Depth of Field

New camera relies on “metalenses” that could be fabricated using a standard CMOS foundry

3 min read
Black and white image showing different white box shapes in rows

Scanning electron microscope image of the titanium oxide nanopillars that make up the metalens. The scale is 500 nanometers (nm).

NIST

Inspired by the eyes of extinct trilobites, researchers have created a miniature camera with a record-setting depth of field—the distance over which a camera can produce sharp images in a single photo. Their new study reveals that with the aid of artificial intelligence, their device can simultaneously image objects as near as 3 centimeters and as far away as 1.7 kilometers.

Five hundred million years ago, the oceans teemed with horseshoe-crab-like trilobites. Among the most successful of all early animals, these armored invertebrates lived on Earth for roughly 270 million years before going extinct.

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Reduce EMI and EMC Issues with Engineering Simulation Software

Save time and money all while delivering accurate and reliable results

1 min read
Reduce EMI and EMC Issues with Engineering Simulation Software

Electronic components and systems exist today in nearly all consumer and industrial products. A major design consideration in all electronics is electromagnetic interference (EMI) and compatibility (EMC). EMI and EMC issues are complex. They can be hard to detect and can be taxing to a design. With the use of engineering simulation software, design engineers can mitigate issues before entering the prototype testing phase. Avoiding the test-retest cycle with simulation can help save time and money all while delivering robust and reliable products.