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Author Topic: Having some sound problems..... Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 03-08-2003 12:05 AM                    At one of our theaters here in town we are having some sound problems. This is what we have. CFS LX2500 console, Simplex 1050 projectors with 5 star sound head. Using jax light with Ultra Stereo procesor. Prcessor is equivilent to the JS 200 series. The problem is extreem noise in all channels. Sounds like it does when you try to manualy strike a lampe only continuously. What I have done. Basically replaced all the cards in the processor with ones from another machine. Problem still there. Problem does not exist in nsync. Only in stereo. Noticed that when you turn on the exciter manually the noise is there and I noticed that the led's on the noise reduction card were pegged out in the red. I changed the signal amp on the cell lines it did not fix the problem. The LED is bright and looks good on the jax light. Problem exists even with the jaxlight out of the sound head. Jax light is powered using a 6volt dc transformer, I think it is 6 I can't remember of the top of my head, that plugs straight into an outlet in the back of the console. I worked at that theater for 8 years and never experienced anything like that before when I was there. Very strange any suggestions that I may be able to do or have them do. Our tech is on vacation till Monday and the closest one to use is in North Carolina.  |  IP: Logged Joe Morris Film Handler Posts: 35 From: Papillion, NE, USA Registered: Jan 2003 posted 03-08-2003 12:09 AM                     what kind of noise are you getting? static or hum? or buzz? or twinkle twinkle little star?  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 03-08-2003 12:13 AM                     Start by removing the solar cell leads to the "proj1" input of the Ultra Stereo. (Make it a point to write down which wires went to which terminals before you do this and have the Ultra Stereo powered off when you do.) Now switch to stereo. Is it still there? If so, then it's in the processor. If not, it's in the Jaxlight. Odds are it is the Jaxlight as lots of people have problems like you describe with them. Once we know which it is, report back and we'll further diagnose.  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 03-08-2003 12:14 AM                    hmmmmmmmmm how to describe it. you know how AM sounds when it is not on a station or when you pass near power lines. I guess that is the best way to decribe it.  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 03-08-2003 12:17 AM                    thing is though It was doing it without the Jax light in the sound head. Socket removed and everything.  |  IP: Logged Jack Ondracek Film God Posts: 2348 From: Port Orchard, WA, USA Registered: Oct 2002 posted 03-08-2003 12:23 AM                        Has anyone installed a hardware-store-type light dimmer in your place lately?  |  IP: Logged Chris Markiewicz Expert Film Handler Posts: 209 From: Glenaviegh, County Tipperary, Ireland Registered: Aug 2002 posted 03-08-2003 12:24 AM                     Could be a ground loop. Check that the lines from the solar cell have the shield grounded only at the processor, not at the soundhead. Even one loose strand touching ground will do it. Drove me crazy when I put in the LED reader.  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 03-08-2003 12:29 AM                    No nothing like that has been installed. I know what you are saying though we had to ground some of the machines in two places to eliminate buzzing that dimmers were causeing but this was not the same type of noise. I have a feeling that the cell lines may be picking up A/C voltage leakage from something and amplifying it into the processor. Could a DC transformer like you would use for a calculator or something possable be going bad inside causing A/C leakage or something. I didn't think about changing that DC plug until I got home and the theater was closed.  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 03-08-2003 12:32 AM                    I did check the grounds. Everything fine there. Oh one thing. THe projector was not running when I was checking things.  |  IP: Logged Marc Jones Film Handler Posts: 82 From: Elizabethtown, KY Registered: Jun 99 posted 03-08-2003 12:47 AM                     Isn't there a small amplifier on the solar cell inputs from the Jax light into the processor? If there is I would verify all of the connections are good or possibly swap the module with another screen. Good Luck  |  IP: Logged Darryl Spicer Film God Posts: 3250 From: Lexington, KY, USA Registered: Dec 2000 posted 03-08-2003 12:51 AM                    I did that too....Thanks for the suggestion.  |  IP: Logged Fabrice Dubourg Film Handler Posts: 43 From: Granville, France Registered: Feb 2003 posted 03-08-2003 01:37 AM                     ground loops problems, maybe, as i can't hear what it sounds like... is the buzz constant or does it appears from time to time? Did anyone made some works in your theatre the days before your problems occured, like electricity work, neon sign? is there in your theatre a neon light blinking due to a starter problem? i had this problem once... is my english understandable ??  |  IP: Logged Bill Langfield Master Film Handler Posts: 280 From: Prospect, NSW, Australia Registered: Apr 2001 posted 03-08-2003 08:01 AM                        What the hell is a Jaxlight? Darryl, Try replacing the CP's PSU unit. Thats what went wrong on a cp65 to me the other day. Bill.  |  IP: Logged Rick Long Jr Expert Film Handler Posts: 211 From: Toronto, Canada Registered: Jul 2000 posted 03-08-2003 09:26 AM                     You say it's there only in stereo. How about Mono? Could it be the NR card in the processor? I've had a few Cat 222's do similar things over the years.  |  IP: Logged Joe Morris Film Handler Posts: 35 From: Papillion, NE, USA Registered: Jan 2003 posted 03-08-2003 12:12 PM                     I'm running a JS 200 in my theatre as well..and I have had similar problems with noise as you describe. I tried the ground loop, tried the cards...and the only other thing that I could come up with was that we are getting a TON of interference. We have buzzes...hums....static....the theatre that the 200 is in has THE worst presentation of all. I had 2 JS 105-95's in my 2 biggest houses...both of them had problems similar to what you are describing...both running Jaxlights. I replaced the first with a 200...still had problems...second with a Panastereo CSSP 1200....no problems...it could just be something interfering with the processor...or it could just be a bad NR card like Rick said...but if your Jaxlight is bad like Brad said, you probably wouldn't get any sound at all.  |  IP: Logged

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