my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Sound and acoustics (Page 1)

This topic comprises 3 pages: 1  2  3

Author Topic: Sound and acoustics Ted Uzzle Film Handler Posts: 19 From: Chicago, Il., U.S.A. Registered: Oct 2015 posted 04-29-2016 02:09 AM                     Might we not benefit from a new forum dedicated to sound, acoustics, and noise control? Whether film, digital, home theater: sound behaves the same. This is my wheelhouse. I think I can bring in experts to help solve problems of all audio and noise-control acoustics. Anybody want? If not, that's okay too.  |  IP: Logged Ken Lackner Phenomenal Film Handler Posts: 1907 From: Atlanta, GA, USA Registered: Sep 2001 posted 04-29-2016 09:18 AM                     I second this request. For one thing, it would be nice to group all audio topics together in one place. Additionally, sometimes an audio topic could apply to both film and digital. If it's a solar cell issue, it's clearly film. If it's an AES channel mapping issue, it's clearly digital. But if it's a B-chain issue, it's probably format-independent. So do you post it in FHF, or the Digital forum? Why not have a forum dedicated to audio?  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 04-29-2016 10:37 AM                     good idea  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-01-2016 09:55 AM                        Ioan Allen's excellent booklet for architects is a great place to start if you are building new. Thx was a direct copy of the Western Electric Blue Book from the 1930s. Nothing new under the sun; just an unwillingness to pay attention and get something proper built. (If fact, thx and blue book are sequentially the same, paragraph for paragraph with a good deal of updating.)  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 05-01-2016 02:40 PM                     Architects seem to despise following someone else's recommendations. I've seen lots of innovative accoustic "solutions" that just didn't work. Build walls as solidly as possible, isolated double walls with absorption between them are really needed between rooms. Add absorption on the walls to get the reverb time down and give some intelligibility to dialog. Put in enough speakers and power. It isn't rocket science. Putting each room and its walls on a floating floor slab is really nice (THX screening room spec) but I doubt if any commercial cinema is built that way.  |  IP: Logged Harold Hallikainen Jedi Master Film Handler Posts: 906 From: Denver, CO, USA Registered: Aug 2009 posted 05-01-2016 05:00 PM                        This is an interesting subject area. I'm on several SMPTE standards committees on cinema sound systems. Here are some topics for discussion: 1. What audio analysis method do you use in setting up equalization? RTA, Impulse Response, other? 2. How many microphones do you use in the audio analysis? 3. Do you use graphic (typically 1/3 octave) with shelving filters, parametric, finite impulse response, or other filters for equalization? 4. Do you use automatic equalization systems in sound processors? Why or why not? 5. How often do you do a "maintenance check" of equalization? What do you typically find has changed during such a check, if anything? 6. In adjusting equalization, do you adjust "to the line" of SMPTE 202, or use minimum filtering that stays within the limits of SMPTE 202, or some other method? 7. How do you set SPL? Methods include C-weighted with full band pink noise, 1/3 octave RTA between 500Hz and 2kHz. Others? 8. What fader level are you generally playing movies at? Harold  |  IP: Logged Rick Raskin Phenomenal Film Handler Posts: 1100 From: Manassas Virginia Registered: Jan 2003 posted 05-01-2016 05:25 PM                     The AFI theater that used to be at the Kennedy Center in DC had car hoods mounted on the right side wall to cut echo. That was a cinder block wall that backed up to the stage of the Eisenhower Theater.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-01-2016 08:36 PM                     I thnk it's a great idea to have a sound section on here, the sound section could be further divided up into different areas.... This may attract more industry people too. Mark  |  IP: Logged Mike Blakesley Film God Posts: 12767 From: Forsyth, Montana Registered: Jun 99 posted 05-01-2016 08:38 PM                        I also think it's a good idea. Sound topics can get lost among the other things.  |  IP: Logged Frank Cox Film God Posts: 2234 From: Melville Saskatchewan Canada Registered: Apr 2011 posted 05-01-2016 08:42 PM                        Everyone seems to agree that it's a sound idea.  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 05-02-2016 12:34 AM                     ^^^^HAAAAAAAAA! quote: Dave Macaulay Putting each room and its walls on a floating floor slab is really nice (THX screening room spec) but I doubt if any commercial cinema is built that way. Great, another spec to add to my mental "future dream theater". I honestly hadn't ever heard of this idea.  |  IP: Logged Jerry Axelsson Expert Film Handler Posts: 107 From: Stockholm, Sweden Registered: May 2005 posted 05-02-2016 01:07 AM                     I know of several commercial cinemas in Sweden which are built on a floating floor. A room within a room.  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 05-02-2016 01:22 AM                        These are to reduce bleed-thru to the adjacent theatres and the reverse...to stop sound transferring to neighboring rooms, yes? Good idea, but a COSTLY one. Here in the US, exhibition doesn't seem all that concerned about patrons watching JUNGLE BOOK from hearing the explosions from the theatre next door screen running CAPTAIN AMERICA. They seem to think patrons don't really need 100% isolation. Theatre owners will invest a nice chunk of change in expanding the concessions counter, but invest in a floating isolation screening room....not so much.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 05-02-2016 05:06 AM                     quote: Harold Hallikainen 7. How do you set SPL? Methods include C-weighted with full band pink noise, 1/3 octave RTA between 500Hz and 2kHz. Others? I've been doing levels also looking at the RTA response when the curve is not very good - some uncorrectable frequencies or simply speakers which wouldn't go very low - as the SPL reading may just give an inaccurate value trying to compensate for the anomalies. In fact, the same applies to the LFE. Glad to know it is something recognised in the industry, I did not know.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-02-2016 01:06 PM                     You don't need to float the whole theatre like at Dolby's screening room in a typical theatre. What you should do, and it isn't too expensive, is to cut the slab and put in an expansion joint. Sound travels through solids better than air so if you can not have any continuous walls/floor between theatres, you are going to improve (reduce) the sound transfer between them.  |  IP: Logged

All times are Central (GMT -6:00)

This topic comprises 3 pages: 1  2  3

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.