Film-Tech Forum ARCHIVE: CP 500 Bass level Not Normal

This is topic CP 500 Bass level Not Normal in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Demetris Thoupis (Member # 833) on 11-02-2002, 10:08 AM:

Hi all,
Another strange matter coming to all's attention. In one of the Cyprus Cinemas, with CP 500, there seems to be a problem with the subwoofer level and response. The particular cinema has a new Cinemeccanica Victoria 5 projector with digital basement reader made by Cinemeccanica. The thing is. When the processor goes to digital, the subwoofer does not seem to work at the time it should. It has to be very very loud in order for the processor to send subwoofer signal to the amplifier. It is abnormal because I know scenes that when played in DTS the Subwoofer ROCKS the cinema but using Dolby Digital with this particular compination for this cinema, something seems not to be working fine. Any suggestions, ideas?
Thanks
Demetris Thoupis

Posted by Antonio Marcheselli (Member # 373) on 11-02-2002, 05:51 PM:

My 2 cent word: I've experienced different levels between DTS and DD IF you set the subwoofer level with an SPL (in my case the DTS had non-existent SW and DD rocks).
Try setting the DTS SW level to 300mV using the DS3 setup disk, you'll see that the sw level will be damn low in DTS also.

If subwoofer level of your DTS is normal, so it is not a Cp500 problems since the 6ch input signal and the DD signal pass throught the same EQ card.

I would say to check the Subwoofer level with an RTA and set all the DTS outputs to 300mV.

Bye
Antonio

Posted by David Stambaugh (Member # 1102) on 11-02-2002, 07:44 PM:

Is that theatre operated by Cinemark?

Posted by Michael Schaffer (Member # 1204) on 11-02-2002, 10:36 PM:

The raised subwoofer level for the digital format has to be activated in the format setup of the CP500. Download the CP500 installation and alignment manual from this very website and look it up.

Posted by Antonio Marcheselli (Member # 373) on 11-03-2002, 05:41 AM:

Michael

What do you mean with "has to be activated"? The CP500 has two Subwoofer level: Digital and Analog. Both has their own setting, but there is nothing to "activate" if I'm not wrong...
The +10dB gain of an user format is just for Non Sync application.

Am I right?

Bye
Antonio

Posted by Michael Schaffer (Member # 1204) on 11-03-2002, 07:46 AM:

You may be right. I don`t have a CP500 within reach to check so I was writing from memory. But I might also have confused it with SDDS setup where you have a specific option to activate subwoofer level offsets.