ReQuest one silent panel

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Shaftish

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Saturday, soft jazz through my ReQuest's. Everything is good, untill..
One of the panels goes mute.
At one time I was able to make it sound, no power for a couple of minutes.
But after that, silence, except from the woofer.

Is my panel dead or power supply? Power On indicator indicates that everything is fine. But that does not say anything about working conditions.

Today, Sunday. I plugged it in and it sounded ok for about 30 seconds, then it died again. So I'm pretty sure that the panel is okej.

So. How do I proceed? I live in Sweden, in not sure how the service network is here.
 

Reverb

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Welcome to the forum!
Guys with more knowledge will be along soon to answer your questions.
 

Brandon Hartwick

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Do you have a volt meter? You should open them up and test the power supply voltage. I have a PDF that details the process but the forum won't let me attach it, I could email it?

One thing to try is swapping the power supplies from one speaker to the other and see if the problem follows. The fact that it powers up and runs for a few minutes leads me to believe bad power supply.

Check it out and report back.
 

Shaftish

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I have switched the panels between the speakers. The weak sounding panel is always weak. The normal panel is always normal.

But, if I raise the volume the panel, sometimes, come to life for a brief moment. Like 1 second. I can do this a couple of times then the panel starts to distort instead of come to life.

Is this really the behaviour of a blown panel?

I have vacuumed, I have showered it. What else is there to do?
 

JonFo

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But, if I raise the volume the panel, sometimes, come to life for a brief moment. Like 1 second. I can do this a couple of times then the panel starts to distort instead of come to life.

Is this really the behaviour of a blown panel?
That might point to a loose solder or joint somewhere. When you pulled the panels, did you inspect them closely for poor / loose solder points?
That comes up often on older panels.
 

Brandon Hartwick

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Interesting that it starts working again, even if for a second. If the coating was bad then it wouldn't work at all, I don't think there's any getting around that.

Is it possible to check the stator continuity with a meter? I guess it might be possible to check between the wire and the stator.
 

Shaftish

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I have checked the solder, they looked okey. But maybe I should have a closer look. As Brandon writes, if it start to play with normal volume the coating
can´t be that bad.

I can only remember 3 soldering point, too up front, one in the back I think. Were is the fourth located?
 

Shaftish

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I turn on the stereo after it have been turned off since last night.
It sounded crisp and clear for 1-2 seconds then a serie of "cracknig" sound then the panel is back to silent.

Maybe I should resolder no mather what, just to make sure.
Is there anything I should think of? How do I even check the solder on the one between the stators? And if it is loose, how do I solder it back?
 

Robert D

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One thing you can do is look at the serial number on the panel itself. Both the panels and the speaker cabinets have their own separate serial numbers. There is a serial number decoder here on our site. See how old the panels are. If they are original, they could be 25 years old or more. Personally, my Prodigy panels were in need of replacement when they were 15 years old. I bought them in 2015 and they were made in 2000.
 

Shaftish

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I'm afraid that the panel is from -97.
So it is time to change panels.

But I can't let go of the fact that it sound okej sometimes, even if it is just for a brief moment.
A fizzy dizzy sizzy sound and then it is dead again.
 

Robert D

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I'm afraid that the panel is from -97.
So it is time to change panels.

But I can't let go of the fact that it sound okej sometimes, even if it is just for a brief moment.
A fizzy dizzy sizzy sound and then it is dead again.
Well, my Prodigy panels actually sounded good when I ran Audyssey on them. With it turned off, they sounded horrible. All Bass. Turns out that Audyssey was basically turning most of the woofer off to compensate for the lack of output from the panels.

I had the panels tested by Russ Knotts here in Ohio and he said the output on the panels was down about 12 dB. One was even worse. So yours are even worse, if they are going out completely and making the weird sound.

Once I replaced the panels, I was able to use the woofers again and gained more than 10 dB! The old speakers required my Marantz receiver to have the gain on those speakers maxed out to the highest level it could go. I think it was +15. With the new panels now, it's only +2.

Now I worry that I put unnecessary stress on my Aragon amp during those years. It had to work extra hard to drive those speakers. I feel stupid. Everyone talks about how hard the speakers are to drive, and I thought that having the gain up that high was normal for the Prodigy.

If I were you, I'd order panels right now.
 

Shaftish

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I think you are 100% correct. I´m tempted to do so, but, coming recession is holding me back a bit. But if it gets bad I can allways listen to good music haha.
 
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