Medianix debuts VMAx 3-D audio chip

Electronic News, June 16, 1997

The MED25007 VMAx 3-D VirtualTheater Digital Audio Processor, a continuation of the company's MED2500X line, implements VMAx VirtualSound 3-D sound technology. Medianix said it is currently the only semiconductor manufacturer licensed for VMAx 3-D VirtualSound technology by Harman Interactive Group, which has exclusive rights to the Cooper-Bauck patents that are the cornerstone of a variety of 3-D audio technologies.

Medianix president and CEO Terry Leeder, commenting on the nature of Medianix' on-going relationship with Harman, said, "This relationship will let us continue to develop digital silicon solutions to meet the needs of the consumer audio market that is our primary focus."

The all-digital MED25007 integrated circuit is based on Medianix's proprietary embedded 24-bit digital signal processor (DSP) and incorporates an on-chip Dolby Pro Logic decoder front-end and the VMAx virtualizer. The Medianix chip decodes surround sound-encoded signals and generates two output channels of virtual 3-D surround sound.

The audio outputs are fed through amplifiers to drive two speakers in the same manner as a traditional stereophonic audio system. The MED25007 can also operate in six-channel Pro Logic Surround Sound mode, thereby offering 24-bit audiophile quality and the option of upgrading from two speakers to six speakers at a later date.

The MED25007 VMAx 3-D VirtualTheater Audio Processor IC is packaged in an 80-pin plastic QFP (PQFP) and is slated to be available in sample quantities early in 3Q97, with volume production scheduled for the end of the same quarter. It will be priced at $15.95 each in quantities of 1,000 units.

With VMAx technology, 3-D sonic imaging is created using two loudspeakers, enabling specific sounds to appear to come from any point in three-dimensional space surrounding a listener, according to Medianix.

Patented Cooper-Bauck transfer functions, or virtualizing algorithms, are at the heart of the VMAx technology and use head related transfer function (HRTF), inter-aural time delay (ITD) and crosstalk cancellation features to create the illusion of multiple speakers surrounding the listener. VMAx technology does not alter the timbre of the real or virtual speakers, or otherwise color the sound.

The MED25007 VMAx IC is targeted at a wide variety of products including televisions, home-theater A/V receivers, DVD-ROM drives and multimedia personal computers, as well as add-on computer speakers. According to Medianix, several companies have already been licensed by Harman to use VMAx technology in their products.

Dr. Floyd E. Toole, VP of engineering at Harman International, said of VMAx technology, "Real 3-D audio produces credible directional and spatial illusions, and the VMAx technology achieves that."

In addition to the single MED25007 chip, Medianix offers OEM designers two kits intended for evaluation and prototyping: a 3-D demonstration board, and a full-featured evaluation board that operates in both 3-D and six-channel Dolby Pro Logic surround sound configurations. The EVB25007-3 3-D demonstration board is priced at $195 and the EVB25007-2 evaluation board is $495.