From tws@xenon.stanford.edu Mon Sep 26 13:39:49 1994 Date: 14 May 1994 23:46:36 GMT From: Toni Walter Schneider To: sci-virtual-worlds@uunet.uu.net Newsgroups: sci.virtual-worlds Subject: 3D-SOUND: Crystal River Announcement COMMERCIAL Crystal River Engineering Inc. announces the ALPHATRON, another price/performance breakthrough in 3D Sound systems. An Alphatron system plays back two sounds (wavefiles) and places them anywhere in a three-dimensional space surrounding a listener. Up to eight systems can be combined into a PC and controlled by one software library to spatialize 16 concurrent sound sources. The complete development kit is priced at $695 per system. Alphatron uses HRTF filters, the only real-time 3D sound method, that can accurately display sounds anywhere around a listener and which has been verified by psycho-acoustic researchers around the world. The Alphatron features Crystal River's HRTF compression method (patent pending), which allows full range, Convolvotron quality, spatialization on affordable hardware. Spatial Sound can be presented over conventional stereo headphones or near phones (stereo speakers placed near the listeners ears). An Alphatron development system consists of a single ISA (PC) slot signal-processing card, and a C software development package, complete with DOS and Windows libraries, example code and an extensive test and demo program. The first Alphatron will ship June 15, 1994. Performance: -two spatialization channels per card, using compressed (equivalent to 256 coefficient/ear) HRTF filters. -40MHz Motorola 56001 DSP. -update rate: 44Hz (88Hz if only one channel is used). -sample rate: 44100Hz. -average delay: 23msec. -input: 64 x oversampled, 16-bit A/D converters. -output: 8 x oversampled, interpolating filters. -stereo crosstalk: 100Hz -100dBV, 1kHz -80dBV, 10kHz -60dBV. Contact: Stephanie Cadet Scott Foster Crystal River Engineering Crystal River Engineering 490 California Ave., Ste. 200 12350 Wards Ferry Road Palo Alto, CA 94306 Groveland, California 95321 tel: (415) 323-8155 tel: (209) 962-6382 net: info@cre.com