President's Message
August 2000

1. John Watkinson writes in Electronics World (3/2000) about stereo reproduction over loudspeakers. He finds traditional loudspeakers inadequate and proposes a test of "information rate" analogous to that of low bit rate encoders. He says the measured bit rate of traditional loudspeakers is "disturbingly low at one tenth the bit rate of the CD. This means that 90% of the disc data is discarded in the speaker. Clearly if this is the case any further increase in recording performance, such as increasing the sampling rate, must be a complete waste of time until attention is given to loudspeakers." Testing of codecs can be invalid because of masking effects of loudspeakers. He also says "A spatially-accurate virtual image can only be obtained if the loudspeaker acts as a point source." [What about a line source?--DBH]. He also gives some clues for listening to low bit rate codecs, e.g. a percussive sound can cause the soundstage to collapse, then return to normal. This effect is inaudible in mono.

2. A DVD double bill of Screaming Skull/Giant Leaches claims to recreate the drive-in experience. It contains cartoons, countdown clock, concession stand ads, coming attractions and more. As a bonus, Audio track two contains...DISTORT-O!, with the truly horrific quality of the drive-in window speaker--coming out of the left channel only. [Digital Flash from Sight & Sound, (781)894-8633].

3. Michael Caloroso writes in Electronic Design (Apr17, 2000) about being a performing musician by night and an engineer by day. In the early '80s, knobs and buttons were replaced by menus. Other musicians laughed at him for buying up their obsolete analog synthesizers they were dumping at bargain prices. Then, in frustration of dealing with menus, they resorted to using the presets in the machines. Suddenly everyone sounded the same. Caloroso started getting more gigs because he had a unique voice and could provide his clients with exactly what they wanted in less time, compared with his musician friends. Finally, the musicians wised up, tired of the learning curve associated with each new interface. Starting in about 1990 they rediscovered knobs and analog synthesizers. The value of his collection has increased at least 500% and he's now in demand for fixing the old gear as well. Now who's laughing?

4. An annoyance in concerts halls is the sound of someone unwrapping a candy. Often they do it slowly to minimize the sound, but that only prolongs the agony. Now a team of physicists has tackled the problem. By recording the sound of crinkled wrappers as they were slowly stretched, they found the noise consisted of individual bursts or pops just milliseconds long and their loudness had nothing to do with how fast the unwrapping was done. Rather the pops occur at random volumes as tiny individual creases in the wrapper rearranged themselves during the overall shape change. [NYT Jun1,2000] A subsequent writer pointed out his procedure for reducing the noise: he holds his legs together, and unwraps the candy underneath them, which shields the high frequency sounds. He still recommends unwrapping only during loud passages.


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updated 11/11/04