Is my Stage center channel panel working?

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Brian_74

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I was in the process of re calibrating my system today and noticed that I couldn't really hear anything coming from the ESL panel on my Stage. The DC power is connected and the blue light is on. However, when I disconnect the power I don't hear any real difference in the sound. Putting my ear close to the panel, I can't really hear anything coming out. All the sound seems to be coming from the tweeter and the woofer.

As a test, I connected the speaker cable from one of my main speakers. Did the same test as above, noting that the panel seemed silent. When I put my ear to the backside of the panel, again I don't really hear anything coming out. Also tried some music and setting my processor to All-Stereo mode.

Is it possible the panel is not functioning? Is there a way to test just the panel? Perhaps if I could disconnect the tweeter, I'd know if any mids or highs were coming from the panel.
 
I have the stage center and you should know if its working. Is the wires in phase on the back of the amp, I assume they would be because you said you already swapped the front out to the center so?

Before the stage center I had the matinee and thought that the panel was old or something. I opened up the top of the speaker to find one of the 3 wires had broken contact so I had to attach it with an iron
 

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Not sure if your Cary Cinema 12 has the ability to generate frequency sweeps on a given channel. If so, you can easily determine if the center is working fine as you'd hear holes in the mid-range sound as the tones are swept from 20Hz to 20kHz. white noise works as well if the Cary has a white noise generator.

If Cary doesn't have this and do what i did. I downloaded a shareware "Test Tone Generator" from Esser Audio onto my laptop and used that to test each speaker in my system.
 
According to the specs, the crossovers are at 450Hz and 2700Hz. So if I played a 1 khz test tone, I should be solidly in the panel frequencies. The cary does have a white noise generator which I have used. The channel balance setting required is consistent with the other channels. I'll check for a loose wire too. Great suggestions!
 
Something abaout the center Stage confuses me. Is it a 2-way or 3-way speaker? I know it has 2 woofers and one tweeter but, if its a 3-way then it has an ESL for the midrange? Is the 2700Hz crossover for the panel or tweeter? Sorry for the newbie question...
 
Something abaout the center Stage confuses me. Is it a 2-way or 3-way speaker? I know it has 2 woofers and one tweeter but, if its a 3-way then it has an ESL for the midrange? Is the 2700Hz crossover for the panel or tweeter? Sorry for the newbie question...

The Stage is a 3-way speaker with cross overs at 450 Hz and 2700 Hz. Thus 6.5 inch speakers (in the Stage ML calls these the woofers) handle frequencies below 450 Hz. The panel handles 450 Hz to 2700 Hz (the mid range) and the highs are from the center 1 inch tweeter. Hope that helps.

Gary
 
The Stage is a 3-way speaker with cross overs at 450 Hz and 2700 Hz. Thus 6.5 inch speakers (in the Stage ML calls these the woofers) handle frequencies below 450 Hz. The panel handles 450 Hz to 2700 Hz (the mid range) and the highs are from the center 1 inch tweeter. Hope that helps.

Gary

Thanks Gary ... Is the panel an ESL panel because its FR is rather narrow. Normal panels go beyond 20kHz. And the panel isn't bipole, is it?
 
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Hola. What I do to listen if the panel is working, with a movie where the actors are speaking, I disconnect from the main AC, the power supply and the voices go away, I get a hole in the voices. Also you can get very close to the stat panel and do the same thing. It takes a while when you disconnect it, but you can tell. Also, when you plug it back to the mains AC, the panel charges immediately. The panel is not bipole, it is dipole, as all ML stat panels. Happy listening!
 
to dmusok: As the panel is flat in the vertical plane, it would have a very narrow dispersion once the wavelengh matches the dimension so we cross to the tweeter to open it up. Otherwise, it would be very directional and make is tough when the speaker is usually below a screen, above, etc. Since all the other panels are much longer in that plane, that is needed.
 
to dmusok: As the panel is flat in the vertical plane, it would have a very narrow dispersion once the wavelengh matches the dimension so we cross to the tweeter to open it up. Otherwise, it would be very directional and make is tough when the speaker is usually below a screen, above, etc. Since all the other panels are much longer in that plane, that is needed.

Peter ...thx for the explanation as it makes sense now. It was also great meeting you at the Newport show last week. I was the fella who was concerned the my new Spire speakers have been seriously upstages by the new Montis models. Thanks for clearing thinks up!
 
So I played some 500 hz and 1 khz test tones over the weekend. I could hear both tone. I unplugged the power for a few seconds and could still hear them however. Roberto, how long does it need to be unplugged before sound goes away? I'd say it was unplugged for maybe 5 seconds.
 
Sometimes, over 10 minutes and still you have the panel charged. But, when you plug back the line power, you can tell the difference in level. Leave the speaker unplugged, use it that way and watch a movie for 20 minutes. Then, while listening carefully, plug it back, and you can tell the differece easer. Happy listening!
 
Sometimes, over 10 minutes and still you have the panel charged. But, when you plug back the line power, you can tell the difference in level. Leave the speaker unplugged, use it that way and watch a movie for 20 minutes. Then, while listening carefully, plug it back, and you can tell the differece easer. Happy listening!

I found with my Cinema i leaving overnight unplugged and then plugging it while it was playing made it pretty obvious. I was being impatient and only waiting 15-30 minutes I could not tell a difference. I have also been auditioning some old (Late 90s) Mirage speakers and even though the MC-si was reviewed as a great center channel, my Cinema i is in a totally different league so that pretty much confirmed for me that it's operating at it's full potential.
 
I noticed some distortion from my stage when listening to "I play Piano" ; a 96/24 blu ray from AIX.

I vacuumed the speaker but still noticed the same distortion .

Did some tests and found the sound was much much better after a few hours of playing sound through the stage.

Has anybody noticed this? Is it normal?


Joel
 
My stage is getting weak after extended use and may have to just buy another panel. Does anyone know of the top of their heads what the cost is?
 
jmschnur,

Distortion of panel section may be coming from PSU board, which may not be providing enough voltage. You may want to try listening with power supply plugged and unplugged and see if it changes anything.
Does it get more pronounced with more volume?

Calling ML will probably get you through standard way of troubleshooting:
- is the blu light on on the back?
- try plugging power supply to "out"
- is the distorted sound coming from panel or tweeter or mid bass drivers?

99% they will point out faulty PSU board.
In my case it was the remaining 1% - detached black cable from panel. It was difficult to troubleshoot and I had to dismantle almost entire speaker.

Distortion from panel was caused by detached black cable.
I also noticed once you unplug power from the speaker and let it play, it will play without any problems for some time and than it will start distorting until discharge completely.

P.S. now I'm left with two 100% working PSU boards for the Stage.....just in case somebody want to grab it.
 
Thanks for the insights.
Seems worse at lower volumes. After an hour or two it is fine.
I will go through the check list and then call.


J
 
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What was the issue with the black wire? A new board is on its way. The stage sounds fine after I wait a long while.

What should I look for if I plug the power into "out"?


Joel
 
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What was the issue with the black wire? A new board is on its way.

my stage black wire issue

long story short: the bottom plastic bracket has a cut out (made by hand) to accommodate three wires from panel. In my case a person who did the cut out, did it too small, so once bracket assembled and bolts tighten the black wire got guillotined.
 

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