Single AA wireless speaker design runs for 40 hours

HiWave, formerly called NXT and know for flat speakers, has released a wireless mono loudspeaker reference design that runs for 40 hours on one AA battery.

It acquired the circuit's low-power audio amplifier technology when it bought Bristol-based fabless chip firm Audium.

"The wireless amplifier is capable of delivering 13W burst power into 8Ω," said the HiWave, "At normal listening volume, 73dB sound pressure level at 1m, a single 1.2V NiMH battery can power the amplifier and its receiver for over 40hours, delivering loud volume levels when required." claimed HiWave.

Using an undisclosed low-bit-rate encoding scheme, the chip relies on the bursty nature of audio to cut power consumption.

"We are not targeting Hi-Fi or professional audio, we believe our audio is in line with consumer requirements, our target is 1% distortion or less," said Audium marketing director Laurence Strong at the technology's launch in 2009.

The reference design, called Monad A1, is electrically compatible with Bluetooth, Wi-Fi, or proprietary radios, said HiWave.

A point-to-multi-point development kit is available which comes with two mono wireless amplifiers, initially fitted with SMSC's Kleer wireless interface on plug-in daughter cards.

An associated transmitter module plugs into Apple's 30pin iPad/iPhone/iPod connector. A USB transmitter is also available.

The design and kit cannot be configured for stereo, although HiWave is considering stereo versions.

Last year, as NXT, the firm introduced a 15W wired amplifier reference design