BAS Message
May 2012

1.  The annual drawing for the Meeting Summary Writer bonus will be held at the May meeting, covering BASS V33-3, 4, and 34-1. Writers are JS Allen (Sean Olive), Alvin Foster (CES 2012), JS Allen (Dave Moulton, JS Allen (Mark Schubin), David Hadaway (Favorite Recordings).

2.  V34N1 of the BAS Speaker has been published. It features the Oct '11 meeting, Sean Olive, by J.S. Allen and CES 2012 reports by Alvin Foster. Also highlights of CES by David Weinberg and Jim Buchanan. 29pp

3.  Along members of other societies, 19 BAS members made the journey to Hartford CT to hear the home theater of Arnold Chase. It seats 103 people on plush red seats in a movie theater ambience with gold cloth side panels. Many thanks to Arnold Chase for his generosity in hosting this meeting. Also to Brian Kobylarz of CT SMPTE who organized it.

The hall is 37' below grade and NC17 (no child under the age of 17 admitted without parent or guardian). Chase talked about how he got into video from the earliest days. When very young he read about the advertised gizmo that would "turn your house wiring into a giant antenna". Not having any money to buy one he took some zip cord and stripped the insulation off the ends. Then he twisted the ends together in a loop behind the TV and plugged it into the AC. His mother was wondering why the lights flickered. Much later he learned about capacitive coupling, and besides the house wiring in that time was armored cable which would shield the signal anyway.

John F. Allen reviewed the technical side of designing the sound system. He uses a mathematical formula to precisely place the surround speakers accompanying the HPS-4000 sound system to give uniform coverage for every seat. It turned out that his placement conflicted with the structural columns. After locking horns with the architect for 4 hours, a compromise was reached: he added two more surround speakers and a steel support column was moved. By toeing in the main speakers virtually every seat has a stereo image. Sensitivity is 109 dB at 1 watt, 1 meter.

It was an enveloping experience with an excerpt from Hugo (which won 5 Oscars including sound mixing). I heard some metallic edge on the sound effects, maybe from what I call the "Foley disease"--that everything you see happening in the picture has to have a prominent sound effect associated with it. (An example is "Contact" with SETI astronomer Jodie Foster. When she pushes a pushpin into a cork board there is a "thunk" and she says "one down and 100 billion to go").

Afterward we were invited to tour and hear demonstrations of his large collection of mechanical music machines including the large orchestrions. Also a side room had maybe a hundred old arcade games, in working order. One that caught my attention involved dropping atom bombs (!).

Explanation: The beauty of NC contours (Noise Criteria) is that a single number gives a spectrum specification. They resemble simplified Fletcher Munson curves at mid and low frequencies. A specification of NC20 means that on an octave basis, the noise in the room does not exceed the NC20 curve at any frequency. A concert hall or recording studio should meet NC15-25. Boston's Symphony Hall meets NC17 (at least when the subway is not passing underneath).

Because no recording was allowed, there will not be a writeup of this meeting.


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