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Meetings and other Notices

BOSTON AUDIO SOCIETY
Meeting notice for November, 2017

Date: Sunday November 5, 2017 at 1PM

Place: Symphony Hall, 301 Massachusetts Avenue, Boston Massachusetts

Guests:
    Brian McCreath, WGBH / WCRB producer for BSO broadcasts
    Antonio Oliart, WGBH / WCRB audio engineer for BSO broadcasts
    Nick Squire and Joel Watts, audio engineers for the Boston Symphony

Topic: We have a great opportunity to visit Symphony Hall and see its audio broadcast and recording facilities. The Boston Symphony Orchestra will be on tour in Japan at that time, so the hall is unusually available to us. We will have as hosts the members of the team that is responsible for the BSO's radio broadcasts and archival recordings.

The main mixing and monitoring studio in the basement of Symphony Hall can accommodate perhaps 10 or so guests at a time to look at the setup and listen to music playback over the fine B&W-based system. We will also use the Chorus Room to meet as a group and hear from our BSO and WGBH hosts, and small groups can be taken to see and hear the studio. We can also bring groups of guests up to the stage of Symphony Hall to see the space, how microphones are hung and placed, and how signals are transmitted to the basement studio.

All BSO programs are recorded on computer in multi-channel form, and archived on hard drives. These recordings may be used for commercial release on the BSO Classics label. When Deutsche Grammophon or another record label is capturing concerts for planned release, they work in parallel with the WGBH/WCRB broadcast team.

Because of Symphony Hall security requirements, we should provide the hall's security team with a list of attendees in advance, so they can be checked in at the stage door. If you're not certain you can come, send your name in anyway and say that you're unsure. This will also enable us to get a rough idea of the number of people who'll be there, so we can plan activities accordingly.

We should be able to accommodate any reasonable number of people; logistics can be adjusted as needed. Please check in at the stage door (the St. Stephen Street end of Symphony Hall) and proceed to the Chorus Room (signs will be posted along the route).

***Note: You must pre-register for this event. Reply HERE to do so.****

Directions: Symphony Hall, 301 Massachusetts Avenue, Boston

From north of Boston: Take Route 93 South to Storrow Drive to the Fenway exit. Then take Boylston St. (inbound) to Westland Avenue. Take a right onto Massachusetts Avenue.

From south of Boston: Take Route 93 (the Southeast Expressway) to the Massachusetts Ave. exit. Approximately, seven lights down on the left will be Symphony Hall.

From west of Boston: Take Storrow Drive to the Fenway exit. Then take Boylston Street (inbound) to Westland Avenue. Take a right onto Massachusetts Avenue.
Or, from the Mass Pike Extension, take the Prudential Center/Copley Square exit. Proceed down Huntington Avenue, to Symphony Hall


Public transportation:

By Subway: Take the Heath Street/Brigham Circle "E" Green Line train to the Symphony stop. Or any other Green Line train to the Hynes Convention Center stop, then cross the street to No. 1 bus or walk 10 minutes towards south on Mass Ave., or the Orange Line to the Massachusetts Ave. stop go north on Mass Ave. to Symphony Hall.

By Bus: Starting in Harvard Square, Cambridge take the No. 1 Massachusetts Avenue bus towards Dudley anywhere along Massachusetts Avenue directly to Symphony Hall.

For further MBTA and commuter rail information visit the MBTA Trip Planner page.


The 2017 New York AES Show (Oct 18-21) has its own page, here:
www.aesshow.com
Also, there's a very useful list of exhibitors HERE

Barry

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...


The BAS Message
November 2017

1.  A recent ad for the Chord DAVE D to A converter claims a noise level of -180 dB. How is this possible? (Theoretically a digital black signal of all zeros would have zero noise). No electronic circuit could be this low noise; there is no way to measure it. The output impedance is rated at .0055 ohm. This does translate to a resistor (Johnson) noise of -180 dBV. However it could only be achieved with an undithered signal source , which would be highly distorted. Any real musical signal will have dither in the recording process and will have a minimum noise close to their signal to noise specification of -127.5 dBV.

Also I am skeptical since the electronics must add some noise to the low output resistance achieved by feedback. I would like to measure one.


email me here


— Webmaster's note: I have distressingly noticed that many companies are incorrectly using the term "signal to noise".
Nominal operating level to the noise floor is 'signal to noise'.
Nominal operating level to clipping is headroom.
Therefore the noise floor to clipping is the 'dynamic range', not signal to noise. Be wary of this.


Below, other meetings and notices which may be of interest to BAS members

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 a new article here: Extracting Numerical Data from an Excel Trend Line

Foster's Test Bench !
by Alvin Foster !    Click the logo: —>
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
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
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   
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

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 !


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   W I N D O W

- AND FOR CONVENIENCE -

AES Future Meetings
www.bostonaes.org

Acoustical Society of America
www.gbcasa.org
SMPTE New England
www.smpte-ne.org

There is a posting of an ABX article, The Digital Challenge by Stanley P. Lipshitz HERE


Classifieds
( A new section! Watch for a full page coming...)
NOTE: offsite links open into a new page.
BAS Members may SELL items here; anyone may BUY.

The Boston Audio Society needs individuals who will write summaries of BAS meetings into *.pages, *.doc, or *.txt files. We usually have audio recordings of the meetings. We pay for your work. Ask about our bonus program for meeting-writers! Contact David B. Hadaway (603-899-5121; dbsys22@att.biz).


Does anyone have a schematic (or any other info!) for any Dunlop-Clarke Dreadnaught amplifier? Email Barry at webmaster@bostonaudiosociety.org


For sale: Audio Precision System 1 audio test system. SYS-322A, s/n SYS1-31968, IMD, BUR, W&F options, A-weighting filter, PCI interface card, rackmounts; asking $5000. Contact Mark Chambers machambers@charter.net


For sale: Several CD storage racks, some made by Bostonwood (www.BostonWood.com/cd.html): Two four-shelf units (25.5"Hx17"Wx5.5"D); One four-shelf unit (25.5"Hx24"Wx5.5"D); Two three-shelf units (19.5"Hx17"Wx6.5"D); one home-made three-shelf unit (18"Hx14"Wx6"D). I have attached a handle and chains to several units, making them convenient open-top carriers. David J. Weinberg (Maryland; 301-593-3230).


Seeking a two-channel preamplifier such as an Apt Holman, an early Hafler, or an early NAD. Must work properly. Fred Ampel (FAmpel@KC.RR.com).


Seeking prereceord Advent cassettes, especially Russell Sherman Beethoven and Liszt recordings, and Handel's Messiah performed by the Handel & Haydn Society under Thomas Dunn. David R. Moran (DRMoran@aol.com).


I am disposing of all my old copies of the BAS Speaker, which go back to 1978, more or less complete. I am going to recycle these with waste paper unless somebody wants them for free. I'll even pay shipping. Doug Pomeroy Audio Restoration & Mastering Services audiofixer@verizon.net


Discography of Test Records. I am compiling a list of technical test records from all recording eras and would like to exchange information in order to confirm, expand, correct and add entries. Send me your list and/or other information about test records and I will send you my discography, which has nearly 200 entries to date. I am interested in commercially released records, as well as discs intended primarily for in-house use by audio engineers, broadcasters and for other special applications. I am generally excluding demonstration discs of the "Super Stereo bouncing ping-pong ball" type unless they include at least some tracks of a technical nature, such as frequency response and tracking tests, etc. Nicholas Starin, Portland Oregon, NTSTestDisc@Gmail.com.


Nashville AES Test CD. (www.AESNashville.org; click the small round symbol where it says "Click here for more info:" to download the four-page description and track list. Use the link on the website under <Products> to send an email for pricing and availability.) From the website: "Assembled 'by engineers, for engineers' after a survey of the needs of a broad cross-section of working audio pros, the disc features 71 tracks of test signals ranging from level calibration tones, noise signals, third-octave tones, polarity and digital meter calibration pulses, bandpassed noise and swept sinewaves. Additional tracks include dry-recorded kick and snare drums, acoustic guitar and piano along with spoken word and a cappella male and female vocals. A data area on the disc features BPM charts, Excel-based calculators and other bonus material. The CD booklet includes tutorial information on using the test disc."


For sale: Three Denon DR-M34HR cassette decks ($500srp) with three heads and live monitoring of the recording, dual Dolby B/C and Dolby HX Pro circuitry. Handles normal, chrome and metal-tape cassettes. Highly regarded in 1988. Gasparo Records used them as duplicators. In good shape. Data at www.VintageCassette.com/denon/dr-m34hr. $125 ea+shipping. Contact David B. Hadaway. dbsys22@att.biz.


For sale: Arcam Solo Movie 5.1 (www.Arcam.co.uk/products,solo,Movie-Systems,SoloMovie51.htm; $4500srp) The manual is downloadable from the Arcam website. I do not have original packaging. $1000+shipping, which will be calculated once destination is determined. Funds transfer or cash only; no checks. Fred Ampel (FAmpel@KC.RR.com).


For sale. Two Tannoy HPD 315 speakers, made in the mid-1970s, woofers might need refoaming. Steven Weiner (SDWeiner@ATT.net; 818-865-0601; Thousand Oaks, CA) is asking $500+s/h. [I have seen a photo; the cabinets and grill look to be close to mint condition. This ad was placed at the request of member Randy Hoffner. DJW]


Seeking: Soundfield Mark IV microphone. Jim Mastracco (James.Mastracco@Verizon.net).


Laserdiscs for sale by David J. Weinberg (301-593-3230; WeinbergDJ@BostonAudioSociety.org) Four have Dolby Digital 5.1 soundtrack. Nine have DTS5.1 soundtrack. Make offer for all or selected items.

TITLE CLV / CAV? ASPECT
RATIO
Video Essentials    
Apocalypse Now CLV 2
Apollo 13 CLV 2.35
Batman (Michael Keaton) CLV 1.78
Blade Runner (Director's Cut) CAV 2.48
Blown Away CLV/CAV 2.35
Crimson Tide CLV 2.35
Daylight CLV 1.85
Evita CLV 2.35
Forbidden Planet CAV 2.35
Golden Eye CLV/CAV 2.35
The Grifters    
Highlander (10th Anniversary Director's Cut) CLV/CAV 1.82
The Hunt for Red October CLV 2.35
In The Mouth Of Madness CLV 2.35
Jurassic Park CLV 1.85
Jurassic Park CAV 1.85
Phenomenon CLV 2.35
Pocahontas CLV 1.66
Pretty Woman CLV 1.85
Raiders of the Lost Ark CLV 2.35
Raiders of the Lost Ark CAV 1.33
Star Wars: Episode 1 - A Phantom Menace    
Toy Story CLV 1.78
Who Framed Roger Rabbit CLV 1.75

Own a movie theater sound system! For sale, top-of-the-line High Performance Stereo HPS-4000-XL screen speaker systems. Three (left, center, right) HPS model 545-4 speaker systems (www.HPS4000.com/pages/fivefortyfive_.html) and two HPS model 545-W subwoofer speaker systems (www.HPS4000.com/pages/545_w_.html). All in perfect working order. The speakers are not light, but consist of modules that can be lifted by two moderately strong men. Truck delivery only, or come pick up. Make me an offer. David J. Weinberg (301-593-3230; WeinbergDJ@BostonAudioSociety.org):

Most units come with user manuals (some also with service manuals), remotes and cartons, as applicable. Make offer:

  • ReplayTV 2020 with aftermarket larger disk drive. Includes lifetime electronic program guide service.
  • Faroudja VP400A video quadrupler. Upscales NTSC video to 960 progressively scanned lines for a front or rear CRT projector. Generates great image on my big screen. I don't need it because I'm modifying my video system.
  • Runco 980Ultra CRT projector (original packing, user and service manuals).
  • Vutec concave high-gain silvered screen. 8' wide, 16:9 aspect ratio, with wallmount brackets. Silvered surface makes it appropriate for 3D projection, as the high gain overcomes the substantial light loss caused by the various consumer 3D projection technologies, and the curved shape can deliver a wide viewing angle with little hotspotting.
  • Lexicon DC1 surround processor, with all options.
  • Panasonic RP-91D DVD player with JVB Digital regionfree mod.
  • Sony DVP-NS755V SACD (multichannel and stereo), DVD, etc., progressive-scan output. $250srp.
  • Tektronix D11 rackmount single-beam storage oscilloscope with 5A15N vertical amp and 5B10N time-base/amplifier.
  • Tektronix 5111 rackmount single-beam storage oscilloscope with two 5A18 vertical amps and 5B10N time-base/amplifier.
  • Teac AN-180 external dual Dolby B processor. Simultaneous stereo record and playback.
  • Pioneer CT-F4242 cassette deck, in excellent condition.
  • Garrard RC88 turntable with Shure M3D cartridge, in excellent condition.
  • Sony XM-5046 car audio amp, 4x50W into 4 Ohms

Webmaster's Corner:
Once again, for 2017 - and on through 2020 (!) here is THE useful industry calendar of audio/related events, with kudos to any and all who put this list together: www.stiernberg.com/industry-calendar

Barry

 

The Boston Audio Society
PO BOX 260211
Boston MA 02126


updated 10/26/17