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Author Topic: Troubleshooting DTS, no voices, center channel hum, etc. Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-17-2013 04:52 PM                     Hi there Film-techers! As some of you may know, I recently took over a decrepit second run 8 screen booth. It has taken me over a month just to get everything operating halfway decent and I've had the time of my life. I love this place. Anyways back on topic, houses 7&8 have DTS that haven't been used in years. Now that I have a little extra time to work on ancellary things, I figured I'd try to get the DTS going. So house 7- There has been a obnoxious hum in the center channel for as long as I know of. I threw the disk in, everything 'works' and sounds quite good(considering) INCLUDING no hum in the center channel, but there are no voices. If I press the bypass/opt fault button on the CP50, the voices come back as well as the hum but its reading the actual soundtrack by then, no? What do I need to be looking at? I'll be honest, I am no sound technician, haha. Do I need to be in another input? I'll check the wiring to see if things look all 'normal' I should note: the bypass button is always depressed in 7&8. To bypass the DTS? So where's my voices? I'll look further... just looking for ideas Thanks in advance.... -Buck  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-17-2013 06:11 PM                     OK so there's this 4 wire thing that's not connected. Where dies it go? Should I even try? Will it blow up? Why isn't it hooked up??  |  IP: Logged Tony Bandiera Jr Film God Posts: 3067 From: Moreland Idaho Registered: Apr 2004 posted 09-17-2013 08:16 PM                     Ok, first a bit of help: Both houses have bad card(s) in the CP 50's. Possibly the power supply unit, likely the CAT 150, maybe the CAT 117. Now the bad news: This situation is probably not a do it yourself fix. You (or the theatre owner) will have to pony up for a technician to do a service call. Figure 2-4 hours for diagnostics, another couple hours for repairs. CP 50's are so far beyond obsolete that your better and most likely cheaper bet will be to find some used processors (CP65, 500 maybe.) If I was local to you I would be glad to come check things out gratis, so maybe try to contact a tech or F-T member in your area savvy with sound systems to do a "courtesy call."  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-18-2013 02:17 AM                     MEGA SAD FACE. Welp, that's the end of the line then. So sad though cause it sounds sooooo much better. Trust me when I say they are not putting ANY money into this booth. I can't say I blame them, but it certainly limits options. Thanks for your help, I appreciate it Tony.  |  IP: Logged Chris Slycord Film God Posts: 2986 From: 퍼항시, 경상푹도, South Korea Registered: Mar 2007 posted 09-18-2013 11:07 AM                     quote: Buck Wilson If I press the bypass/opt fault button on the CP50, the voices come back as well as the hum but its reading the actual soundtrack by then, no? Yes, bypass would be reading from the print's soundtrack.  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 09-18-2013 02:40 PM                     CP-65s can be had for about 300 pounds {~$500) these days. I've just picked up a complete set of Dolby Digital and DTS gear for a two projector installation for a very low price. I'm making up the cables now, did the timecode 'Y' cable for the DTS today. Now just need to raise the money for the installation.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 09-18-2013 03:46 PM                     The lack of centre channel in Dts is not a 150 issue since that is only used for optical matrix I suspect that the wireing is wrong on the cp50 there should be a small relay board that breaks the input to the EQ cards and transfers the output of the dts to the input of the eq cards i suspect that either there is a bad relay there or a wiring error also that is often the source of the hum  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-18-2013 05:13 PM                     The ribbon cable from the dts splits three ways. The bigtwo legs jm21 and ??? Both go to little chips before hitting the back of the cp50 between the cat 64 and cat 115/150 cards. The third and smaller leg bs22 also goes to a little chip but isn't hooked up to anything. It has 3 wire forks right on the chip and one more wire that runs off the chip  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-19-2013 04:21 PM                     Would anyone happen to know where that should go?  |  IP: Logged Stephen Furley Film God Posts: 3059 From: Coulsdon, Croydon, England Registered: May 2002 posted 09-20-2013 02:04 AM                     Buck, take a look at the manual for the DTS-6, not 6D, in the warehouse. There are two versions of it, one dated 2002 and one older. Both show a three-split ribbon cable which looks like it could be what you have. It's on page 6-9 in the 2002 edition and page 24, though that page does not have the number printed on it but it's between 23 and 25, in the older one. Hope this helps.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 09-20-2013 10:48 AM                     the small board is for switching the subwoofer if memory serves what you are refering to as chips are actualy small dip relays and they form a break and insertion point between the cat 150 optical matrix and the cat 69 eq cards  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-23-2013 02:59 AM                     Thanks Stephen. Apparently they're logic break boards. Anyways, on the wiring diagram on pg 44, DTS6 to CP50, it claims the BS22 isn't used so that's that. I'll move onto house 8 and see how it's doing. It's got a disk stuck in the player though or something, we'll see what's up with that.  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-26-2013 11:18 AM                     Ok so all of the above was for house 7. Moving onto house 8, I had to replace one of the drives of which we had spares. There was a disk shattered into AT LEAST a hundred pieces inside of it, and even after getting it all out, it wouldn't open/close/boot so anyways, I got it changed out. Disks seem to read fine, the player has all the lights on as it should, but when I un-press bypass, there is straight up no sound. Nothing. The 'clip' light on the amp will even go out. So that's where we are on house 8. Who wants to come fix DTS in 2 houses for a couple hundred dollars??  |  IP: Logged Buck Wilson Jedi Master Film Handler Posts: 894 From: St. Joseph MO, USA Registered: Sep 2010 posted 09-29-2013 01:48 PM                     I would really like to get this fixed. A fellow projectionist and I finally got non-sync 'working' in all 8 houses. What a huge clusterf- that was... Some need a bit of tuning, but we're still working on that. Houses 7&8 need to be in bypass for the feature, out of bypass for non-sync music to play. So there's another annoyance of the processor not working properly. Anyways, I basically have nothing to loose. The hum is really bad in 7- to the point of customers often complaining. How do I tell if/what card is bad? Starting with house 7, I believe it's closer to actually working. You know what... I just remembered there are spare cards in this booth... I know there is at least one of the cards with the bypass button attached, I think there are others... I'll have to check. Thanks for all your help, guys. This is a huge labor in love for me and everything that we can get back up and running is just so so rewarding and I'm learning more every day than I could've even imagined. I love this place dearly, and something tells me that if we can get back to a decent presentation, who knows what the next year will bring.... -Buck Wilson  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 09-29-2013 05:29 PM                     Frankly I think you need a decent service engineer to come in and deal with this you do not have any of the test gear to diagnose the problems and fix them Some things do need to be left to the proffesionals  |  IP: Logged

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