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Author Topic: Academy filtered SR on a CP65? John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 11-11-2006 09:48 PM                     Tonight we had one of those occasional prints with a damaged analog soundtrack that sounds better in mono than SR (Who Killed The Electric Car). There was physical damage on to the soundtrack making SRD unreadable, and SR had continuous repetitive "ticking" sounds. Dolby A and Dolby SR both sounded bad, but mono sounded passable (still occasional ticks, but not continuously). Is there a straightforward CP65 modification to turn on the Academy filtering (and maybe even the mono summing?) with SR noise reduction? Or is there a good postprocessing filter that is useful for these situations? Thanks! --jhawk  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 11-15-2006 04:14 PM                     No takers? Steve? Gordon? Sam? --jhawk  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 11-15-2006 04:35 PM                        Might be easier to use format 01 and switch on the sr. Louis  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 11-15-2006 04:42 PM                     Whats it worth to ya? Out of curiosity...do you have real SR or the dreaded 222SR/A....it would have particular problems with this sort of noise. As to the Academy filter...it is not done as it was on the earlier units (on the Cat 109 card). The Academy filter resides on the Cat 242 and is POST Cat 150 decoder and as such is only on the Center channel. Furthermore, the Cat 242 treats Mono as a separate input on the Muxes. You can get 3-channel mono from that by removing the inhibit diodes on the Cat 443 board. To get the filter on just the center could be done with some PCB alterations. It would require the removal of R140 (disable the regular Center channel audio) and then placing a jumper from Pin 4 to Pin 5 on the Center channel mux (IC5). You would then have to contend with mono-gain trim. In short, it isn't something that you really should do...the CP65 just does not have the means to deal with the problem. You'd be better served to take the audio outboard via the optical preamp outputs ...perform some miracle on the audio....then bring it back in via say Non-Sync and do the 2:4 decode from there. BTW...how are those cue markers coming? Steve  |  IP: Logged Charles Greenlee Jedi Master Film Handler Posts: 801 From: Savannah, Ga, U.S. Registered: Jun 2006 posted 11-15-2006 06:43 PM                        Oh, I was thinking using an external SR decoder. We have one, sitting around for some reason. All it does is apply the SR noise reduction, does not do any matrixing.  |  IP: Logged John Hawkinson Film God Posts: 2273 From: Cambridge, MA, USA Registered: Feb 2002 posted 11-15-2006 10:57 PM                     Cue markers...a continuing sad embarassment on my part No 222 SR/A here. I can never rember the card number though, 300-series...the 350 I guess. It does sound not-worth-doing if it would be adding 2+ switches to make it happen. I dunno about miracles. I had hoped to get the benefit of SR noise reduction. Perhaps pulling signals after noise-reduction, summing them (on the theory that mono has better SNR), then piping them into the miracle box, and straight to the center EQ+amp. Any suggestions on what such a miracle box should do? I suppose I have an RPM26z to play with to pull off miracles. Of course, this print is long gone. The question is whether to have some sort of "canned solution" on hand for the next blue moon. I suppose it's not likely to be worth it. --jhawk  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 11-16-2006 08:26 AM                     If it is just ticking...try to find an SAE impulse noise suppressor. They were around in the 70s/80s for use with record players. No doubt in this digital era there are means for doing it in software but there may be a timing issue introduced then since one will want to remain in lip sync. Steve  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 11-16-2006 04:28 PM                     Also a Burwin DNR type of NR would help  |  IP: Logged

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