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Author Topic: CP650 Sound Failing With Apogee Projector Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-23-2006 11:17 PM                       The fader issue is a real can of worms. Even though the dubbing theatre was set up to record at 85dBC at 7, it sounds too loud to many people in real theatres, so the fact that 5 runs OK does not always mean the house was set up using the wrong fader level. The original idea of 7 of 10 was to have 10dB to spare on the volume control for any number of reasons, old prints not recorded to the Dolby standard, etc. Today it is useful to have only 10dB to spare as too much room on the fader will lead to someone blowing a subwoofer out the entrance. The subs in Dolby applications are set to be able to hit 103 dB max at fader 7. Add 10 dB to this and you have a very difficult to achieve SPL of 113, in a theatre of any size.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-24-2006 06:50 AM                     Er Sam...the subs on a Dolby Digital film, with the fader set to 7.0 CAN achieve 113dB since the digital output for the subs adds 10dB right out of the gate. Adding 10dB to that gets one 123dB. Anyway...another issue with the CP650 is that its 85dB is not the same as ALL previous processors...it will give you a 2 dB louder system. Why? Because the Cat 85 Pink Noise generator was set up that way...I believe it was set for 380mV output instead of 300mV. This PN level was carried into the CP500 era but was changed for the CP650 where it became 300mV reference...the net result is the PN in the CP650 is 2dB quieter which means you will turn the outputs up an additional 2dB and thus the whole system is 2dB hotter than previous processors using the exact same set up procedures. As to the analog processors using fader setting of 7...there is the headroom that Sam mentions there is also VCA tracking. Take an older processor that used discrete component VCAs (something with say a Cat 117) and set the fader to 7 and set every output perfectly...then reduce the fader to 3 or 4 and now look at the channel to channel balance. As you get towards the lower end of the scale, they will not track as good to each other. So by putting the fater in the 1-2 O'Clock position, you also but the VCAs in an area where they should maintain the channel to channel balance better even if the fader is adjusted a number up or down. Personally, I have always found that Hollywood mixes their films too damn loud...to the point that ruin the potential dynamic range of the track by having everything so elevated (except the dialog...it is normally too quiet referened to everything else). Larry Blake tends to mix films that are listenable at 7 though (Oceans 11 and 12 are examples). Just look for "Swelltone" on the credits. In fact, he had T-shirts made that said something to the effect of "I listened to Oceans 11 at 85dB and nobody complained."  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-24-2006 08:24 AM                        deleted...others said it earlier. Louis  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-24-2006 10:01 AM                       Sorry, where is my math? Steve is right for once. It's getting boring having the sudent correct me.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-24-2006 04:09 PM                     So many times, no less  |  IP: Logged Phil Hill I love my cootie bug Posts: 7595 From: Hollywood, CA USA Registered: Mar 2000 posted 05-24-2006 04:17 PM                  I have empathy for you Sam. I HATE it when us young know-it-all punks correct the old-timers! HA!  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-24-2006 04:20 PM                     Now we know why you HATE so much!  |  IP: Logged Phil Hill I love my cootie bug Posts: 7595 From: Hollywood, CA USA Registered: Mar 2000 posted 05-24-2006 04:22 PM                  But Steve, I'm a LOVER, NOT a Hater...  |  IP: Logged William Collins Film Handler Posts: 18 From: Porirua, Wellington, New Zealand Registered: May 2006 posted 05-25-2006 01:28 AM                     Brian, check the rollers around the sound drum. not for dirt but for the bearings. I've discovered that one of my rollers is binding nicely, its not damaging the film yet, but its certainly not helping. best way to test this is to left all the projectors off in the morning, and just spin it with your fingers, and if it sounds louder than the rest and doesnt spin as freely then it might be the bearings have gone. I recently discovered this on one of my two, its ok to run for now but im waiting on new parts. i was the guy who set this up that mentioned it to me. and he has spoken to strong and for some strange reason, this is only word of mouth so far so dont depend on it, the core for the roller was made just a bit to small for the bearings to fit, so when new they worked fine, after a bit they wear out, and it also explains why the sound improves. as the rollers heat up due to the heat transferance it expanded just enough to make it loosen up! Check this out with you gear, might be the same issue!  |  IP: Logged System Notices Forum Watchdog / Soup Nazi Posts: 215 Registered: Apr 2004 posted 12-10-2010 11:12 AM                 It has been 1660 days since the last post.  |  IP: Logged Eric Robinson Jedi Master Film Handler Posts: 538 From: Santa Rosa, CA Registered: Jan 2005 posted 12-10-2010 11:12 AM                     We just opened an art house with 5 Apogees. 4 of them run in analog all the time. All 5 projectors are warbling but fortunately our Dolby Digital house is able to mask the warbling effect. On one of the machines I have replaced the sound drum bearings and have checked and cleaned all pad rollers and bearings in the Apogee basement analog sound reader area. I can find nothing more to do to improve the sound other than engineering my own version of a friction roller like the 5 Star uses. Someone had mentioned that there were redesigns to improve warble. Does anyone know where to find information about these new designs. I can't seem to reach anyone at Ballantyne for some reason...probably out for the holidays.  |  IP: Logged

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