Quiet

You may have noticed the lack of news articles for the past couple of weeks. I have moved half way around the planet, and hence have not been available. All should be back to normal in the next couple of days.

LDS’s new high force shaker

Ling Dynamic Systems has released a new shaker, model V9 for use in automotive and aerospace testing. It has a maximum force output of 105kN, and dispalcement of 75mm. It is water cooled and hence is quiet, making suitable for squeak and rattle testing.

Dolby releases surround sound headphones

At the International Consumer Electronic Show (CES) in Las Vegas this week, Dolby displayed their new headphones for use with their 5.1 surround sound technology. The headphones almost eliminate the “listener-fatigue” problem, where the listener perceives sound coming from inside their head.

Read the press release on the Dolby web site.

Endevco’s new accelerometers

Endevco have released 2 new accelerometers for vibration measurements. The 2222D is a lightweight accelerometer (1 gm), the 7268C a tri-axial piezoresistive accelerometer that can be used for automotive crash testing.

They have also release a new signal conditioner 482B which is an 8 channel rack mounted board that is compatible with the TEDS (plug-and-play) type sensors.

Quiet fuel cell cars

General Motors’ vice-chairman of product development, Bob Lutz, was interviewed at the Detroit Motor show this week (January 2003) and said that fuel cell cars are so quiet that they are considering making artificial engine noise sounds and playing them through the car’s audio system.

Austin Acoustics bought for $4m

ESCO Technologies has bought Austin Acoustics Systems for $4 million. Austin Acoustics make acoustic enclosures for audiometric testing and the recording industry.

Audio Spotlight for sale

Holosonics is selling the “audio spotlight”, an ultra-sonic loudspeaker than generates audible noise by the non-linear behaviour of air. The radiation pattern is a few degrees, so that sound does not disperse like a conventional loudspeaker. A special signal processing amplifier is required to convert audible signals into the ultra-sonic range.

Read more on the Holosonics web site.

Vasci group divided into two companies

With the investment of ESI Group into Vibro-acoustic Sciences, the makers of AutoSEA and other software products, the company has been split into two groups. The sales office in San Diego and Detroit are now called ESI North America. Vibro-Acoustic Sciences now only exists in San Diego and is a research and develop company, working on improving AutoSEA and continuing to develop the Resound software.

Read the press release on the ESI Group web site.

JMC develops low noise fan

JMC Products has developed a DC motor for fans that is significantly quieter than conventional motors. In a conventional fan motor a square wave switching voltage is applied to the stator that generates torque ripples and vibrates the entire structure which makes a ticking noise. JMC have reduced this noise by changing the switching frequency to 25kHz, above the range of human hearing.

Read the JMC media release here.