This is topic Smart MOD VI in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=003803
Posted by Mike Fitzgerald (Member # 1304) on 08-03-2002, 08:30 PM:
We have a smart sound system and have been having a problem where in the loud action scenes the voices drop out and sound like you are in a shower all kind of faint and distant. I was told this is becuse the Smart system does not have noise reduction built into it. Any suggestions as to what we could do to tyr and improve this.
------------------
Fitz
Posted by Gordon McLeod (Member # 33) on 08-03-2002, 08:48 PM:
The mod 6 has noise reduction for a type and emulation for SR so whoever said there is no noisereduction doesn't know what they are talking about.Is there a possibility that the amplifier is being overdriven and is going into protection on the centre channel?
That said which version of the circle surround matrix do you have.
If it is the analogue one press the reset button on the card and thatshould restor the centre channel.
There is a component change to prevent this from happening
The other question id to the input level. Who did and when was the a chain done last? If the input level is too high it is possible to overdrive the circuitry in both the nr section and the matrix.
Also did this happen from day 1?
Posted by Bruce Hansen (Member # 281) on 08-04-2002, 02:36 PM:
Something like this could also happen if you have a speaker, or speakers, or an amp input (if balanced) out of phase (connected backwards).
Posted by Gordon McLeod (Member # 33) on 08-04-2002, 03:30 PM:
Out f phase speaker would not cause it to "drop out" just a loss of level but not to a drop out amount
Posted by Oscar Neundorfer (Member # 458) on 08-05-2002, 06:56 AM:
Mike,We have had 3 or 4 reports recently of this type of thing happening, but ONLY if you have the newer analog matrix in the MOD VI (NOT the older DSP matrix).
It seems that momentary power glitches can cause the microcontroller chip on the matrix to get into a strange mode, and when this happens the center channel can disappear. I have come up with a easy fix to solve this problem IF that is what is happening in your case.
You said this happens in loud action scenes, so my solution may not help you unless the loud scenes are causing enough of a power line disturbance (due to heavy current draw by amplifiers in loud scenes) to cause the glitch I mentioned. So I have a question or two:
Does the sound come back to normal on its own after the loud scene passes? If so, then I doubt the MOD VI is at fault. More likely this would be something like Gordon said about an amp going into protection mode.
Do you have a monitor that can monitor both processor outputs and amp outputs? If so, then check the center channel processor output on the monitor when the problem occurs. If the signal is present there, but is NOT present on the amp output, then the processor is OK.
If the problem does not cease on its own, is there anything you can do to restore normal operation, like, for example, powering the system off and then back on?
If you have the analog matrix, it will have a little red pushbutton on the front edge of the card, just to the left of the DIP switches. When the problem occurs, try pressing that button to see if the sound is restored.
Are you having any other problems that might be related to power line glitches, for example, computers or computerized equipment acting strangely or re-setting for no apparent reason. If so, then you may have some power quality issues to deal with.
Lastly, the MOD VI indeed does have noise reduction in it. Please don't hesitate to call me if I can help you in any way.
1-800-457-6278
------------------
Oscar Neundorfer
Chief Engineer
SMART Devices, Inc.
oscar@smartdev.com
Posted by Gordon McLeod (Member # 33) on 08-21-2002, 09:51 PM:
So what was finally found to be the problem
Posted by Mike Fitzgerald (Member # 1304) on 08-21-2002, 10:26 PM:
We are not real sure. After talking with Oscar at great lenghts about this we tried a couple of his suggestions. First we retightened all connections on the MOD VI and made sure none of the wiring insulation was in the connectors. Then we reseated the card in the BACP head unit. I think it might have vibrated loose and was causing the intermittant problem. Since we did those items the problem has not reared it ugly head again. So we are letting sleeping dogs lie for now.------------------
Fitz