Film-Tech Cinema Systems
Film-Tech Forum ARCHIVE


  
my profile | my password | search | faq & rules | forum home
  next oldest topic   next newest topic
» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » MOD IIC sound issues

   
Author Topic: MOD IIC sound issues
Richard Miller
Film Handler

Posts: 33
From: Lafayette, IN, USA
Registered: Aug 2002


 - posted 01-24-2004 03:51 PM      Profile for Richard Miller   Email Richard Miller   Send New Private Message       Edit/Delete Post 
We are having some sound issues with our MOD IIC. We recently hookied up DVD players that run all day through the music board. However, 2 out of 4 theaters now have sound leaking from the music into the other formats (digital, mono, and such). Does anyone possibly know why this is or how to fix it?

 |  IP: Logged

Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99


 - posted 01-24-2004 04:01 PM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
Turn the small white trim pot on the edge of the format board to max and then set the levels with the trim pots on the output card
the music fade circuit has a range of travel and you have exceeded it
there is some discusion else where on the site on this issue

 |  IP: Logged

Oscar Neundorfer
Master Film Handler

Posts: 275
From: Senoia, GA
Registered: May 2000


 - posted 01-24-2004 09:31 PM      Profile for Oscar Neundorfer   Author's Homepage   Email Oscar Neundorfer   Send New Private Message       Edit/Delete Post 
Richard,

There is only a certain amount of attenuation of the music signals when the MOD IIC is in a film format. If the signal level going into the music VCA's on the output card is excessive, then leakage occurs.

Gordon is basically right about setting the levels, although I usually recommend setting the overall music level trimpot to about the 3 o'clock position so that you have a litle upward volume adjustment left. This is the trimpot on the right-hand side of the Format board, visible with the front panel removed.

With the trimpot in the 3 o'clock position, adjust the left and right music input trimpots on the MOD IIC Output Card for the desired level in the auditorium. These are the bottom 2 pots as I recall.

Also, you may want to check for possible grounding problems because this too can cause leakage through the ground side of the signal wiring. You can isolate the music input signals from the DVD players with audio line isolation transformers placed between the DVD players and the MOD IIC music inputs. Sometimes this has helped greatly for this problem. Remember that decent transformers can get expensive. However I believe Mouser has the 42TU016 line transformer really cheap. I used these for years in our music distribution amp, and considering their price, they do a decent job. I no longer use the Mouser part because I have them made especially for us now. But I _think_ they are still available from Mouser.

 |  IP: Logged

Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99


 - posted 01-24-2004 10:05 PM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
I guess the reason I set the main fade trim pot to max is to stop the ease f overpowering the levle of what I deem as preshow nonsynce (abit that may be advertising)
Since the problem didn't appear before and often I have found that DVD adverising has the audio fed through the pre non sync distribution amp I have noticed that many didn't check the relative level sets between those two points just like with the mod 5's they often have the front panel trim at the min and the internal pots up hig

 |  IP: Logged



All times are Central (GMT -6:00)  
   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.

© 1999-2020 Film-Tech Cinema Systems, LLC. All rights reserved.