Film-Tech Cinema Systems
Film-Tech Forum


Post New Topic  Post A Reply
my profile | my password | register | search | faq & rules | forum home
  next oldest topic   next newest topic
» Film-Tech Forum   » Operations   » Digital Cinema Forum   » Strange Sound Problem.

   
Author Topic: Strange Sound Problem.
Carlos Villalpando
Film Handler

Posts: 21
From: Villa de Álvarez, Colima, México
Registered: Jan 2013


 - posted 10-21-2013 08:49 PM      Profile for Carlos Villalpando   Email Carlos Villalpando   Send New Private Message       Edit/Delete Post 
Hi!
Last sunday I attended a 2D screening of Gravity at a local 12-plex.
It was on one of their bigger screens (50ft screen) and 5.1 sound.
We arrived, took our seats and waited, as usual. But when the show started there was something unusual.

A Sears commercial started playing and there was a strange problem with the sound. It was surrounds only... this commercial has a song in it (http://www.youtube.com/watch?v=Njw21HkDYN0 , in case you wanted to see it [Razz] ) and you could only hear some music (in a very weak level) coming from the surrounds (and no lyrics).

I went to the auditorium entrance and told the employee about it, he called on the radio and told me they were "checking it".
When I came back to the auditorium I could see two employees at the booth looking at the projector. A loud popping sound came from the center speaker and then sound was back at the front. Just with one little detail... Center and surrounds only.. No side channels.

Once again I came to the auditorium entrance and told the employee about it, and when I came back in the auditorium I could see the two employees again through the booth window. No popping sound this time.. just suddenly side channels started sounding again. Luckily, this was fixed just before the last trailer played.

After those problems were fixed, the sound was very good with nice dynamic range.. the crescendo at the beggining gave me chills. [Smile] There had been a long time since I heard a movie sound this good.

May be worth noting this is an all digital multiplex.

Any ideas what the problem was and what caused it? And what did they do to solve it?
I believe it was a Christie projector.. I don't know about the processor.

Thanks in advance. [Smile]

 |  IP: Logged

Carsten Kurz
Film God

Posts: 3278
From: Cologne, NRW, Germany
Registered: Aug 2009


 - posted 10-21-2013 09:09 PM      Profile for Carsten Kurz   Email Carsten Kurz   Send New Private Message       Edit/Delete Post 
They probably forgot to switch on the amps...

- Carsten

 |  IP: Logged

Carlos Villalpando
Film Handler

Posts: 21
From: Villa de Álvarez, Colima, México
Registered: Jan 2013


 - posted 10-22-2013 05:45 PM      Profile for Carlos Villalpando   Email Carlos Villalpando   Send New Private Message       Edit/Delete Post 
It was the first show of the day, so I guess it could be that. Thanks [Smile]

 |  IP: Logged

Joe Redifer
You need a beating today

Posts: 12856
From: Denver, Colorado
Registered: May 99


 - posted 10-22-2013 07:04 PM      Profile for Joe Redifer   Author's Homepage   Email Joe Redifer   Send New Private Message       Edit/Delete Post 
Sounds like they were switching off the amps at night via the switches on the amps themselves. What's the point of that? When you arrive, you turn ALL the breakers on at the circuit box and go about your day. Or you have Film-Tech's automation power them up for you automatically.

 |  IP: Logged

Mike Blakesley
Film God

Posts: 12108
From: Forsyth, Montana
Registered: Jun 99


 - posted 10-22-2013 10:34 PM      Profile for Mike Blakesley   Author's Homepage   Email Mike Blakesley   Send New Private Message       Edit/Delete Post 
I think the power switches must be the cheapest thing in any piece of equipment, when they SHOULD be the most heavy duty. I've had power switches fail in everything from our digital projector to lighting controllers when I was a DJ.

 |  IP: Logged

Marcel Birgelen
Film God

Posts: 2233
From: Maastricht, Limburg, Netherlands
Registered: Feb 2012


 - posted 10-23-2013 04:02 AM      Profile for Marcel Birgelen   Email Marcel Birgelen   Send New Private Message       Edit/Delete Post 
quote: Joe Redifer
What's the point of that? When you arrive, you turn ALL the breakers on at the circuit box and go about your day.
Maybe the breakers aren't capable of handling the peak load that happens, when you turn on everything at once? Granted, automation would be the an obvious solution for that, or a simple APC managed PDU that can be configured to switch on every outlet with a programmed delay.

But this could also be the result of some sloppy maintenance.

 |  IP: Logged

Stephen Furley
Film God

Posts: 3040
From: Coulsdon, Croydon, England
Registered: May 2002


 - posted 10-23-2013 06:40 AM      Profile for Stephen Furley   Email Stephen Furley   Send New Private Message       Edit/Delete Post 
quote: Mike Blakesley
I think the power switches must be the cheapest thing in any piece of equipment, when they SHOULD be the most heavy duty. I've had power switches fail in everything from our digital projector to lighting controllers when I was a DJ.
While I can't say that I've never had a power switch fail it's been very rare, just a couple in the last few decades. I doubt that my switches are any better than yours, or that yours are switched more often. Is this on 120 V? I wonder if switching the higher current takes a heavier toll on the switches?

 |  IP: Logged



All times are Central (GMT -6:00)  
Post New Topic  Post A Reply Close Topic    Move Topic    Delete Topic    next oldest topic   next newest topic
 - Printer-friendly view of this topic
Hop To:



Powered by Infopop Corporation
UBB.classicTM 6.3.1.2

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.

© 1999-2018 Film-Tech Cinema Systems, LLC. All rights reserved.