audio

A standard home audio speaker converts electrical signals into sound pulses in the air (via a somewhat cumbersome cone). Those sound waves in turn cause tiny variations in air temperature, as waves disrupt surrounding air. So, scientists reasoned, why not create sound waves through those temperature fluctuations themselves?

In 2008 researchers built a loudspeaker from carbon nanotubes that creates sound from this thermoacoustic effect. Now Finnish researchers have created a far more simple thermoacoustic device using tiny aluminum wires suspended over a substrate, opening thermoacoustics to a far broader range of applications.

Technological advances have brought audio recording a long way over the past several decades, but, as with so many things, microphone recording is limited by the very technology that has pushed it forward. In this particular case, that limit is the diaphragm that converts sound into electrical signals by measuring vibrations made by incoming sound waves. Because each diaphragm has its own characteristics, all microphones are not created equal; and because the sound waves are converted by these diaphragms, there is always some degree of mechanical interference with the sound.

Violins made by the Italian master craftsman Antonio Stradivarius are worth millions of dollars for their unparalleled sound. And that's great, for the handful of musicians who can afford these centuries-old instruments. This month, a new violin made from wood treated with a fungus actually trumped a Stradivarius in a blind listening test, offering hope for violinists who want high tonal quality at an affordable price.

ProTools? Bah! Let's make some vinyl! As part of Jerszy Seymoour's Coalition of Amateurs exhibition at Luxembourg's modern-art museum, Mudam, artist Yuri Suzuki created records from scratch in an afternoon.

The world certainly isn't simple, and trying to express real-world dynamics in the form of an equation has long been a challenge. Realistic computer-simulated sound has been particularly tough to get right, and some of the hardest dynamics to recreate have been the movements and sound of water.

Scientists at Cornell have now announced a system that can look at a 3-D motion rendering of water--waves, drops, anything--and algorithmically create the dribbles, gurgles and plops it would be sounding, were it in fact real.

If you're looking to attack a pirate ship, forget cutlasses and cannon balls. Go full speed ahead with an MP3 sonic blast. At least that's the latest method being used in sea warfare, as highlighted last week when a sonic blast was used to scare away Somali pirates from attacking a chemical tanker close to the Horn of Africa.