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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Video Friday: Turkey Sandwich

Your weekly selection of awesome robot videos

4 min read
A teleoperated humanoid robot torso stands in a kitchen assembling a turkey sandwich from ingredients on a tray

Video Friday is your weekly selection of awesome robotics videos, collected by your friends at IEEE Spectrum robotics. We also post a weekly calendar of upcoming robotics events for the next few months. Please send us your events for inclusion.

CoRL 2022: 14–18 December 2022, AUCKLAND, NEW ZEALAND

Enjoy today's videos!

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New AI Speeds Computer Graphics by Up to 5x

Neural rendering harnesses machine learning to paint pixels

5 min read
Four examples of Nvidia's Instant NeRF 2D-to-3D machine learning model placed side-by-side.

Nvidia Instant NeRF uses neural rendering to generate 3D visuals from 2D images.

NVIDIA

On 20 September, Nvidia’s Vice President of Applied Deep Learning, Bryan Cantanzaro, went to Twitter with a bold claim: In certain GPU-heavy games, like the classic first-person platformer Portal, seven out of eight pixels on the screen are generated by a new machine-learning algorithm. That’s enough, he said, to accelerate rendering by up to 5x.

This impressive feat is currently limited to a few dozen 3D games, but it’s a hint at the gains neural rendering will soon deliver. The technique will unlock new potential in everyday consumer electronics.

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Get the Rohde & Schwarz EMI White Paper

Learn how to measure and reduce common mode electromagnetic interference (EMI) in electric drive installations

1 min read
Rohde & Schwarz

Nowadays, electric machines are often driven by power electronic converters. Even though the use of converters brings with it a variety of advantages, common mode (CM) signals are a frequent problem in many installations. Common mode voltages induced by the converter drive common mode currents damage the motor bearings over time and significantly reduce the lifetime of the drive.

Download this free whitepaper now!

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