n.b. Chrome users need to refresh their browsers to ensure they have the latest content.
Meeting held April 24, 1996, University of Washington Communications Building, Seattle, WA.
n.b. Chrome users need to refresh their browsers to ensure they have the latest content.
Meeting held April 24, 1996, University of Washington Communications Building, Seattle, WA.
|
||||||
Audio on the Internet - a panel forum
David Scheirman began with a handout outlining issues that affect audio quality on the Internet and a reprint of comments from Investor's Monthly about the outlook for Internet broadcasting. Steve Mack and Aurika Hays from Progressive Networks gave an overview of the RealAudio Internet audio broadcasting system. Armed with a laptop, a pair of Genelec monitor speakers, a projection LCD screen and Ethernet T1-style Internet connection, they described and demonstrated RealAudio. How can you stream digital audio over a 14.4 modem? As expected, it basically involves doing mono only, a 4kHz bandwidth, and heavy-duty codec compression algorithms. A non-standard transmission protocol is used that does not worry about retrying lost packets. The coder is sensitive to input levels, so inputs must be heavily compressed, and also equalized. Voice tends to be better than music. The sophistication of the codec is improved for version 2, and is meant for 28.8 modems. Users download the RealAudio playback software for free, and can also use a personal RealAudio soundfile encoder/server for free. Commercial content providers must purchase software to encode and serve the streams to provide on-demand audio material for multiple end users. Steve spoke of upcoming "splitter technology" to improve distribution efficiency, where data is distributed to ISPs, who then distribute RealAudio to end users. Aurika mentioned that variable bit-rate encoding is being examined, but is found wanting to date. In response to general questions about the sound quality, Aurika said, "We're at the point now where the dog doesn't play chess well, but the dog does play chess." Many sound examples were played live over the Internet - classical music, Johnny Cash, Internet Radio Hawaii. The problems of preparing audio material for encoding was discussed. Generally, compression and midrange EQ boost is used, but always tuned by ear depending on the material. When are you going to do video?? Not soon, but a demo of synchronized multimedia was shown. The RealAudio activated links to graphics, like a synched slide show. Audio engineering problems include soundcard quality and poor handling of sound by PCs, and bad loudspeakers. Cal Perkins described his introduction to soundcards, buying one for his son. He found that the audio engineering left much to be desired. He also tested 40 cards for a magazine review, and found that most were not very good and poorly designed from an audio systems standpoint. The PC hardware market seems to be driving audio quality down. In response to a question about IEEE 1394 (FireWire), Bob Moses described a feasibility project he completed for Microsoft - 100Mbit and up speeds for data transmission. David Scheirman asked, Who fills the gap between the low quality PC audio hardware market and the high quality pro audio industry? Large corporations are getting involved in the Internet, and money will be made. Steve Mack related that their live events get an audience of about 150 people, whereas 50K people might make it pay, or one needs advertisers. Some copyright problems of Internet transmission were discussed. David Scheirman asked audience member and sound mixer Dave Stevens if a musical act like Sonic Youth would like to be broadcast over the Internet. Steve Mack commented about the quality of the live sound mix for encoding. David asked the audience for a show of hands: Who didn't have a PC? Who didn't have an ISP? Who hadn't listened to Internet audio of some sort? Who wasn't satisfied with the sound quality? Many questions were asked about RealAudio.
|
||||||
