Film-Tech Forum ARCHIVE: CP500 SW Output Issue

This is topic CP500 SW Output Issue in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Jeremy Weigel (Member # 4208) on 08-08-2011, 06:58 PM:

I am getting L/C/R fed to thru the SW output for some reason. Discovered this while I was down by the screen and could hear dialogue coming thru the sub while movie was playing. So after the show I went in to the "Diagnostic B-Chain Sequence" and sure enough the signal present on the sub amps lit up when in L/C/R (with more on the C) and nothing on the SW. Checked wiring and all is good. Went in to B-Chain Setup and the same results. Has anyone experienced this before on the CP500?

Posted by Louis Bornwasser (Member # 3063) on 08-08-2011, 08:17 PM:

Was this lf dialog or full freq dialogue? If in A or SR, some crosstalk might be normal. Not so with digital. Louis

Posted by Sam D. Chavez (Member # 1841) on 08-08-2011, 09:05 PM:

Very good point Louis. Someone should definitely check whether the 500 is in SR.D or has reverted to analog. Block the light on the digital reader to be absolutely sure.

I'm guessing it's playing in analog.

Posted by Jeremy Weigel (Member # 4208) on 08-08-2011, 10:51 PM:

We are using the External 6 Channel input for digital playback. The thing that is most concerning is that I can not get pink noise when selecting SW only. The only time I can get signal to the SW is when the L/C/R channels are producing pink noise. The SW signal is much strong though when running pink noise through the center.

Posted by Sam D. Chavez (Member # 1841) on 08-08-2011, 11:37 PM:

I have to confess to not remembering the procedure of setting the sub level. It seems to me it had to do with making sure the bar on the RTA display was to be equal sound pressure level wise to one of the front channels in optical analog and be 10 dB above that bar from SR.D.

It may involve turning off front power amps for a moment to be able to measure it.

It seems they are way too loud from your description.

Guttag, get in here! You who knows everything and still remembers.

Posted by Jeremy Weigel (Member # 4208) on 08-09-2011, 12:51 AM:

The thing is, I did a full b-chain on this auditorium back in May and everything worked fine.