| Meetings and other Notices |
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| The April Zoom and In Person Meeting |
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Date: Saturday Afternoon, April 26, 2025 2-4PM EST
Location: Colonial Cadillac, Conference Room on 2nd floor (staircase in showroom)
201 Cambridge Rd, Woburn, MA 01801
Please do not park in customer area in front of the showroom.
Featured Guest: Ed Ting, science writer, teacher, and musician
Topic: “Audiophilia Nervosa – One Man’s Fifty-Year Journey Towards Obtaining Good (and bad) Sound”
Ed Ting has been fascinated by recorded sound since he was old enough to talk. When he was nine, he took his father’s tape recorder and aimed the mike at the evening news, and broke the recorder in the process. Since then, he has owned many audio systems, including a $5 Radio Shack transistor radio, a hand-me-down Garrard/Fisher stereo, a portable CD player with headphones, to a full-sized system in a dedicated audio room today. Hear about what he’s learned, what he got right, and what went wrong in his quest for good sound.
Ed is a well-known amateur astronomer whose works have appeared in Sky & Telescope, Skywatch, Astronomy, Discover, and Popular Mechanics magazines. He is a National Science Foundation Ambassador to Chile, a Mission Patagonia ambassador, and a NASA Solar System Ambassador. His science-themed YouTube channel has 65,000 subscribers and gets two million views a year. Ed’s creative works have appeared in literary journals. He is a past winner of the NH State Flash Fiction contest and was selected as Writer-in–Residence at the Noepe Center for the Fine Arts in Edgartown, Massachusetts. He teaches creative writing at New England College and at various writing retreats across New England. Ed holds a BS in Electrical Engineering from the University of Illinois, an MFA from New England College, and a MALS degree from Dartmouth, where he produced an award-winning thesis on astronomical imaging. He is a retired Category 3 bicycle racer, a classical/New Age pianist, and an enthusiastic fudge confectioner.
There will be light refreshments
Boston Audio Society
PO BOX 260211
BOSTON MA 02126
617.271.6588
Ken Schwarz is inviting you to a scheduled Zoom meeting.
Time: Saturday afternoon, April 26, 2025, 2:00 - 4:00 PM Eastern
Meeting ID: 843 6359 7657; Passcode 622621
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Hope to see you then.
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THE BAS MESSAGE
April 2025 |
Miscellaneous News
1. The BAS is looking for a new webmaster. The current webmaster will train you and hand it over to you, and provide support as necessary. The website is written in simple HTML. You will need a computer and a high speed internet connection (you will need to download a 6GB backup in a reasonable amount of time). $300 is the annual payment. You may be asked to support admin of the BAS Facebook pages as well.
2. V46n1 of the BAS Speaker has been published. It features the January 2024 meeting, Open forum and Flea Market, Low Noise Design for MC Preamps by David Hadaway and Over the Record Counter with Moeran’s Symphony in G minor. Also a note on speaker protection circuits by Tom Perazella.
3. Compression at the BSO
It is generally believed that compression as used in FM broadcasts is non-reversible—you can’t get back the original. However the BSO (Boston Symphony Orchestra) stream on WCRB uses a simpler form known as limiting. The output follows the input up to a threshold, then infinite compression is applied—for all input levels above the threshold the output is constant. You can see this in the waveforms where the signal envelope looks as if a hedge trimmer has clipped them off. (BASS 43n1p4) (However there is no actual clipping, only gain reduction). It’s easy to imagine extrapolating the signal to recover the lost peaks using a judicious amount of increased gain, say 4-8 dB. Of course the overall level has to be lowered to allow for the higher peaks. An attack time of 50 msec and release time of 1 msec might be reasonable. Since the threshold level is always the same, just below full scale, the process can be automated. Comments?
[I thought that an expansion program would work but then realized that it can’t work when there is no change of amplitude with time, as in this case where it is flattened off. I then thought of Izotope’s “Declip” feature which looks for clipped waveforms and extrapolates upward in amplitude to give a rounded waveform. This works very well for its intended purpose, but in this case it had no effect. It is looking for sharp edges and there are none here. I then did it manually (4 dB) and you can hear the result, before and after, at https://dbsystemsaudio.com/tchai.wav. I’m sure there are editors out there that will do everything I would want, but the money and time involved are beyond my interest.]
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Below, other meetings and notices which
may be of interest to BAS members |
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JUST RELEASED !
A fantastic historical video!
Ken Berger and Kenton Forsythe are the founders of EAW (Eastern Acoustics Works) and they discuss, with terrific overlaid graphics, the history of, well, pretty much every audio thing Boston from the early 70's.
18 minutes and right here: https://youtu.be/fPfQEK0b0mI
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A Boston issue - As MIX magazine reports:
Sound Museum owners cry foul as their tenants likely secure new spaces without them
While the headline sounds like someone has sour grapes, the complete story of how the closure of this crucial Boston rehearsal studio is being handled is far more nuanced and complicated -- particularly since it brings up issues of gentrification, government support of the arts, non-profits' ethics and more. Full Story HERE (WBUR-FM Boston (1/11/23)
And here's an update:
www.wbur.org/news/2023/01/25/charlestown-rehearsal-studios-musicians-boston
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MAHLER 3
In the recent (April 2022) performance of Mahler’s Third Symphony at Boston's Symphony Hall by Ben Zander and his Boston Philharmonic, the recording was done with the three main spaced omnis with two more farther back. No accent mikes or chorus microphones were used nor, it turns out, were they needed. Remarkably, this produced a recording that is as close to the Symphony Hall experience as may be possible.
The info is here: www.bostonphil.org/concerts/2021-2022/bpo4-mahler3
Here is the recording in its entirety as a single .WAV file; 44k / 16 bit; 1hr 47 min
Mahler Sym 3 CD.wav 1.1GB
(For those of you with editing software note that the .wav file HAS markers to denote the movements.)
Here is the exact same Symphony 3 with the movements separated as FLAC files, 48k / 24 bit as a ZIPped file: Mahler 3 Zander as FLAC.zip 1GB
IF you'd like further Gustav Mahler info... https://en.wikipedia.org/wiki/Gustav_Mahler
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Shop Talk
Shop Talk was a WBUR program about Hi Fidelity, music, speakers, tape recorders, etc. Enjoyed by many during the 1970s, the program's format was ‘talk’ and interviewing major audio luminaries. It was a forerunner of the popular program Car Talk!
Peter Mitchell and Dr. Richard Goldwater were the original hosts. They were later joined by Brad Meyer. Here, John Allen interviews Scott Kent:
Shop Talk John Allen talks to Scott Kent on SPEAKERS.mp3 (81Mb 1:27)
Shop Talk John Allen talks to Scott Kent on TAPE RECORDERS.mp3 (79Mb 1:26)
There is also an episode track on the BAS CD and here is that Description:
Track 12. "Shop Talk", WHRB-FM, November 5, 1984.
Peter Mitchell (on the left), Richard Goldwater, MD (center) and E. Brad Meyer (right) introduce the show with a 1932 stereo recording and prepare to talk with guests Mark Davis and David Moran, both then of dbx corporation.
Shop Talk, which through most of its ten-year life on WBUR featured just Mitchell and Goldwater, was the precursor of Tom and Ray Magliozzi's "Car Talk". As we finished our 9:00-10:30 stint every Saturday morning, Tom and Ray would take our places and begin joking with each other. Eventually the station manager figured out that they were funnier than we were, and that more people drove cars than owned hi-fi equipment, and fired us. Until then, the show publicized the Boston Audio Society, vastly increasing attendance at our monthly meetings. The show came back for a time during the '80's on the Harvard station WHRB, where we appeared once a month as guests of HRB stalwart David Elliott. [EBM]
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| BAS MICROPHONE CLINIC REPORT ! |
| In September 2009 the B A S held a microphone clinic, testing 37 different microphone models. The ambitious nature of the clinic effort, the extent of data collection, the number of individuals involved in microphone testing and in writing various sections of the report, and the complexity in determining how to construct the clinic report and make it available to members resulted it not being published until now. The dataset is extensive.
Representative samples were included in the abbreviated report in "The B A S Speaker"
(Fall 2015; v37n3)
Go to the MICROPHONE CLINIC PAGE for more...
...and don't forget, here is the master list of microphones in the world
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When collecting and plotting "noisy" data it is often useful to have Microsoft Excel plot a Trend Line through it. If that data is to be used for further work, it may be necessary to have an X-Y table of the Trend Line. That is not easy to get and this paper will show how to do it.
Joseph DeMarinis has an article here: Extracting Numerical Data from an Excel Trend Line
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Foster's Test Bench !
by Alvin Foster ! Click the logo: —> |
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The rapidly-becoming-famous BAS Headphone Test Article is now available in the BASS VOLUME 25, ISSUE 4, on Page 17, available HERE  PDF 3mb |
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Visit our PODCAST PAGE for:
The LIVE video podcast of our meetings,
Archived video of past meetings (only one so far!),
and Audio Podcast interviews by Alvin Foster |
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There is a supplemental and further explanation addendum paper to the E. Brad Meyer / David Moran paper published in the September, 2007 issue of the AES Journal. That page, which documents the experimental protocol and audio systems/source material is here:
www.bostonaudiosociety.org/explanation.htm |
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| There is a Power Point Presentation of the lecture given by Dr. Barry Blesser at the March 2007 Meeting. The Meeting page synopsis is HERE; the Power Point Presentation (as a web page) is HERE |
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Some earlier BASS issues, previously available only directly by mail, are now available online, on the BAS SPEAKER page, HERE
Show your appreciation for the immense amount of dedicated work that went into both the original writing, gathering, editing and printing, PLUS the more recent scanning and conversion to PDF format, by joining the Society, HERE !
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A L L O F F S I T E L I N K S O P E N I N T O A N E W T A B O R W I N D O W
- AND FOR CONVENIENCE -
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