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Topic: UltraStereo Problems

Charles Lubner
Film Handler

Posts: 78
From: Milwaukee, WI USA
Registered: Sep 1999

posted 12-25-1999 02:00 PM

I'm having sound problems with my UltraStero unit. It's a 105-195, with a basic QSC amp. We have one speaker behind the screen, and 4 on each side wall.

After installing a CD player shelf in the rack, I had to rewire all of the components because I shifted them around to make room. Well, my manager threw out all of my wire, so I had to resort to using 4 color thermostat wire to rig it up! The problem is, after the rewiring, everything sounds hollow. The surrounds aren't very loud at all, and the main speaker doesn't seem to have any "kick" to it. I'm thinking it's maybe an amp problem, cuz ever since the rewiring, the red light for Clip #2 keeps coming on.

Suggestions? I downloaded the JS-200 manual and I'm currently reading it to try and figure things out.
s

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Chris Erwin
Expert Film Handler

Posts: 195
From: Olive Hill,KY
Registered: Oct 1999

posted 12-25-1999 03:31 PM

I'd get some better wire as soon as possible. That thermostat wire is more than likely not heavy enough to handle the load. Some amps read a "clip" when there is an impedence mismatch, or power is lost through the wire in form of heat. Are the wires going to the speakers warm? If so, run the amp as low as you can until you can get heavier wire, and watch the clip and how hot the amp itself is getting.

Hope that's some help. Merry Christmas!

--Chris

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John Walsh
Film God

Posts: 2490
From: Connecticut, USA, Earth, Milky Way
Registered: Oct 1999

posted 12-25-1999 03:37 PM

It seems the problem is in the QSC amp, not the Ultra-Stereo processor, although I don't know much about Ultra-Stereo.

Throwing out the existing wire and using thermostat wire in it's place is a big no-no. And after moving things around, there could be several problems, not just one. I'm not trying to be a pain, just saying it might not be possiable to fix right away.

(I'm guessing) that the two outputs of the processor (front and surrounds) went to the two channels on the QSC. Could you have reversed which signal went to amp input #1 and amp input #2? The "clip" light is indicating that the input is too high, while the other channel seems too low. If you are sure that everything is wired correctly, it's as good a guess as any.

Most processors have three wires for each output: high (sometimes marked "+"), low (sometimes marked "-") and ground. Could your have reversed ground and low- sometimes that causes a reduction in volume.

Generally speaking, I think you will have to give us more clues to be able to get anywhere. Is the sound distorted? Does it sound ok at the booth monitor? Is there a emergency "bypass" setting, and what happens when you use it, etc....

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Scott Ribbens
Expert Film Handler

Posts: 118
From: Los Angeles
Registered: Oct 1999

posted 12-25-1999 04:47 PM

Get some Belden 8451 or equivalent wire and get rid of that thermostat wire. The clip light on that QSC,(1200, 1400, 1700?????) is on one Channel only, or are both of them on? Recheck all of your connections from the processor to the amps, amps to the speakers, processor and amp outputs to the booth monitor. See which channel, if only one clip light is on, to see if it is the one going to the stage or the surrounds. If the QSC is one of those series one amps I listed above, it is possible that the gain control knobs were accidently turned when moving the equipment around. As the knobs on that series of amps are on the back of the amplifier, you might not have noticed it. Make sure that they are in the position that they were in before you moved everything around. Is the clip indicator(s) on all of the time, or only during louder passages? It is possible that the fan in the amp, if so equipped, has stopped running, that can cause heat build up problems. It is rare on the QSC, but I did run into that problem one time.

Since the clip indicator/s started to come on after moving and re-wiring things, I would also check to see if some of that thermostat wire is shorted, maybe a couple of nicked wires when you stripped them? That could explain some of it. Please keep us informed!

------------------

Scott

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Charles Lubner
Film Handler

Posts: 78
From: Milwaukee, WI USA
Registered: Sep 1999

posted 12-25-1999 04:51 PM

I plan to get the correct wire as soon as some stores around here open up. I've turned down the surround adjustment screw all the way down because that seemed to be the source of the clip going off on the amp. The main speaker in the auditorium sounds a lot better than it did yesterday. However, the surrounds aren't working at all (this was before I turned them off). When I listen on the booth monitor, everything sounds fine, but not in the auditorium.

All this would have never happened if Marcus would just pay for service techs instead of having untrained people do stuff! About 4 months ago I had to singlehandedly install a large popcorn machine, which included rewiring a 220 plug because they didn't want to pay for a service call to the popcorn people!

The QSC is a 1400. And the gain controls were not touched, they both are turned fully towards the right.

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David Johnson
Film Handler

Posts: 54
From: Melbourne Vict Australia
Registered: Oct 1999

posted 12-26-1999 12:19 AM

I would suggest that you get someone in who knows what he is doing. It looks like you only have center surrounds so I would not expect too much anyway.
David

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Ken Layton
Phenomenal Film Handler

Posts: 1452
From: Olympia, Wash. USA
Registered: Sep 1999

posted 12-26-1999 12:43 AM

Sounds like processor-to-amp wiring for the surround channel or possibly one of the surround speakers/wiring has a problem.

If you need some shielded wire quick and cheap, try Radio Shack's # 278-514 (20ft spool for $3.99) or # 278-513 (50ft spool for $7.99).

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Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999

posted 12-26-1999 01:58 AM

>>"If you need some shielded wire quick and cheap, try Radio Shack's # 278-514 (20ft spool for $3.99) or # 278-513 (50ft spool for $7.99). "<<

Let us not condone this sort of thing...cheap inappropiate wire is what got him into this mess.

My guess is inexperience is another factor.

Steve

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"Old projectionists never die, they just changeover!"

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Bruce Hansen
Jedi Master Film Handler

Posts: 847
From: Stone Mountain, GA, USA
Registered: Dec 1999

posted 12-26-1999 03:57 PM

You may have something out of phase. This can cause cancelation of audio. Make sure all "+"'s are wired to "+"'s and "-"'s to "-"'s.

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Scott Ribbens
Expert Film Handler

Posts: 118
From: Los Angeles
Registered: Oct 1999

posted 12-26-1999 05:49 PM

"The main speaker in the auditorium sounds a lot better than it did yesterday. However, the surrounds aren't working at all (this was before I turned them off). When I listen on the booth monitor, everything sounds fine, but not in the auditorium."
_____________________________________________

Sounds like the speakers may have been out of phase as was stated above. Since you seem to have surrounds in the booth monitor and not in the theatre auditorium, I assume that you are listening to the processor outputs on the booth monitor. You may have shorted the amp output lines when rewiring, and that in turn caused the suround channel to go bad in the amplifier. You probably need to get a new, or used, amp . You should make sure that none of the wires are shorted in the surround chain or at the amp. Also make sure that when the amp is replaced, all of the wiring is double checked, and that all wiring is done with the POWER OFF.
If you have to, unplug everything while rewiring, then after everything has checked out, no shorts, phasing correct ect..., power the system back up.

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Scott

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David Johnson
Film Handler

Posts: 54
From: Melbourne Vict Australia
Registered: Oct 1999

posted 12-27-1999 03:18 AM

If you only have one stage channel then what is out of phase too? even if you use the incorrect cable it will not produce the symptoms you have only hum.
David

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Stephen Jones
Master Film Handler

Posts: 314
From: Geelong Victoria Australia
Registered: Jun 99

posted 12-27-1999 08:12 PM

I think the best way to fix these problems rather than fiddel whith it and get know where, is to bugger the expense and call in a tech.At least you will get things back to normal with out these headaches you have been haveing.It really gives me the s***ts when managers cry poverty when things in the bio need to be replaced or repaired.They always let you know how much it costs when the 6 monthly service is being carried out.But they dont care about the costs when they purchase new equipment for their office I have seen this happen time after time.

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Rick Long
Jedi Master Film Handler

Posts: 759
From: Toronto, Ontario, Canada
Registered: Nov 1999

posted 12-27-1999 10:03 PM

Are you absolutely sure that the hook-up of the C.D. player hasn't introduced a very high-frequency signal into the system, causing the amps to "top out" at a frequency above that of human hearing?
Disconnect the damn thing.

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 12-28-1999 01:28 PM

Check the outputs of the amps and the inputs
The QSC have a balanced input unsure that the - side is attached to the E terminals of the processor and that the + side of the speakers is connected only to the monitor inputs
You can create some interesting ground problems with connections to monitors

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Kenneth H. Williams
Film Handler

Posts: 2
From: Oklahoma City, OK. USA
Registered: Dec 1999

posted 12-28-1999 08:52 PM

Please verify that the solar cell wiring to the Ultra-Stereo is correct...that is, not out of phase. Also check the hearing-impaired wiring...I've had sound problems due to shorts, etc. with these units. Don't think the problem is with the amp...most likely the wiring. Any chance the dip-swithces that program the Ultra- Stereo for the correct output got accidentally moved? These are on the backplane over on the right side as viewed from the rear...verify correct formatting of these switches also. Please keep us informed as to the solution.

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