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Discussion Starter #1
Do most or all plasma screens make a buzz or humm? The sound is very much like a highvoltage wire.

Thanks
 

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Not all, but some do. Like mine does usually, depending how you run it or what it's displaying. This model is known as having a propensity for it. If it was running the way they set them up in stores, I imagine the buzz would be quite "loud", whereas I can hardly hear it and probably mostly do because I listen for it. :) Certainly can't hear it when any sound is turned on, which I guess is the way most people use their displays...

I don't think I've ever heard a plasma in the 42-46" size buzz though, it tends to be the larger ones IME. Also the ones with thinner glass tend to do it more IME, but I don't know if that's a fact or coincidence. A web search should tell if the buzz is "normal" for your model or is an anomaly of the example. If the buzz on a store display bothers you a lot, I'd completely stay away from that model. In my case, I knew about it in advance, and obviously decided I could live with it (which is surprising, because I'm usually picky about stuff like that). Another thing is my buzz is MUCH less in the summer (especially during this "heatwave") compared to during the winter months, something I haven't quite got an explanation for except to say somehow humidity might affect it...so that means if a buzz on a model you're looking at is "loud" now, I'm suggesting it might get louder in the winter.
 

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Discussion Starter #4
Thanks. I have a 58" new VT25. I went to three stores yesterday and never heard a buzz on any Panasonic/Samsung plasma.

I am going to have a tech come out and have a look. Maybe its the power source?

I hope it can be rectified, even if the noise is reduced I would be happy. I love the picture quality that's for sure so rather keep the set then send it back.
 

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no buzz here with my panny 42px75

my friends samsung 42a450 buzzed enough to make him return it but he is super anal over things like that

my father in laws samsung 50a450 doesnt buzz ethier
 

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^ So you *did* hear a small one buzzing, eh. That could especially be more of a problem considering you're probably sitting close to it...

I forgot to mention mine is a Pioneer 9G model, which have a reputation for buzzing, IIRC it's even mentioned in the manuals. Doesn't seem to be a heat-related thing, more related to the mechanical construction as best I can tell (in this design's case) but I don't think Pio ever said...
 

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yah he was viewing at around 6 ft but is very anal about it. i personaly never heard the "buzz" but im sure it can happen.

Heck i had an old 13" tube that buzzed like crazy. nothing inherant to the technology . just the way it is built i guess.
 

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^ Heck, *I'm* anal about it! :) But if you wanted the Pio PQ, that was the possible downside, there's always one...

I think the volume of the buzzing also varies a lot by how and where a display is mounted. A small alcove may amplify, maybe the wall would too for a wall mounting, even the distance the display is mounted off the wall, or maybe being out in the open on a stand could make it louder. My buzzing isn't nearly loud enough that I tried doing anything about it, but I know it's there even if I can't hear it with any sound on. OTOH the slightest electronic hummm and I'd have been all over it (because that's usually a user/wiring issue.)
 

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Many of the older CRTs and some newer plasmas seem to buzz as they are "stressed". For example as an all-white screen comes up, or something else really bright.

I have a Watt Meter and you can see the Watts rise on those sorts of scenes on Plasmas and CRTs. (LCDs are not affected in the same way). This would seem to indicate that the buzz relates to more stress on the power supply, or perhaps other electronics. For example, on my Panasonic plasma, the Wattage used for an all-black screen is almost 1/10th the usage for all white, with most programming about 1/2 way.

With TVs, the power consumption can be brought down with a proper optimization which may help to minimize buzz, while also providing better picture quality.

http://www.digitalhome.ca/forum/showthread.php?t=76161

You can tell if this is the case by switching away from the default picture mode to something more "appropriate" like cinema or custom, or similar, or by reducing contrast somewhat.
 

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^ Yes, the volume definitely depends on the amount of "stress" on the power supplies. For instance, I use an "energy saving" mode largely because the buzz is very noticeably less. (Besides the proper viewing mode/calibration.) Frankly, I couldn't see any PQ diff in that mode, keep meaning to go back and compare now that the TV is older and I'm more used to it... And "energy saving" mode with a largish plasma is very relative. :) Likewise the buzz is almost absent when the display is black.

But what I was getting at was many plasmas of similar screen size use roughly the same amount of power. Some buzz to an extent depending on what's displayed, and some don't at all, ever. It seemed to be the more expensive thin-glassed ones that did it more, and that's what led to my hypothesis: We know that if we take a small vibrating source, and couple it to a large thinnish "unsupported" diaphragm, the vibration source will be largely amplified. Like in a speaker. So that's what I guessed might be happening with some displays: the PSs' vibration is getting amplified by the thin glass = (poor) construction method. PSs and glass could have been isolated better. I think it's a possible explanation, or at least a major contributing factor...

Edit: My Pio 151 manual says buzzing is "appropriate for plasma technology". :) Of course that's nonsense, it's not "appropriate" at all.
 

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Discussion Starter #11
Yay I had my TV exchanged today and after a few hours of use-no buzz like I had on my first VT25 :) I am glad because the picture is awesome on this set.
 

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My 50G20 buzzes a little too much for my liking so I'm going to ask Panny to check it out. I suspect a a noisy PS is the culprit.
 

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Before going to a lot of trouble you should try to find out if buzzing is common for your model.

Based on the theory that the factory would assemble your TV better than the repair person would re-assemble it if they replaced a PS. :) I think you know where I'm going here, especially if your display is ineligible for a store replacement. It is pretty rare the manufacturer themselves would replace a display with a new one unless something is truly "broken" and not worth repairing. "Annoying" unfortunately isn't covered in warranties...
 

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A few owners of this set have had noisy PS boards replaced & it corrected it. I cannot return my set as I've had it for about 4 months now. I figure I'll inquire to see if it can be improved or not but I'm not fretting it too much either. It seems some of this series buzzes more than previous gens but what is normal is hard to say.

If I make any progress I'll report back.
 

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I just bought a Samsung PN58C6400 and it buzzes like crazy. It's absolutely unacceptable. Back it goes...

I've calibrated many Samsungs...heard nothing like this before.
 

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I have a 50" Plasma LG with the all glass front and I can hear it buzz a little when "stressed". It's in my bedroom so I usually watch with the volume low where it's more noticeable - if it was in the family room I'm sure we wouldn't notice it at all.

I'm kinda annoyed by it but it took me 5 months to hear it in the first place. Now that I know it's there I guess I'm more sensitive to it. If there's sound coming out then you can't hear it at all. But if the TV was on mute and the room was quiet I could certainly with my eyes closed (literally) tell whether a white picture or black picture was being displayed.

Oh well, I guess I'm going to just have to get used to it.
 

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I have a Panny TCP50G25 which hums. Contacted Panasonic and they blamed the Satellite system plugged in, even though it is not directly plugged in ( goes into the receiver and the receiver out ). I will test the hum tonight without anything plugged in and if it still exists, will be back on to Panasonic.
 

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Yes, or at least switching to a mode like cinema, or reducing contrast to say 70-75 in Custom to see if the issue goes away, especially if you're still on the defalt "Vivid/Dynamic" mode. If it does go away, then a proper optimization is likely in order. If it still buzzes, then you may wish to return it. I assume there are fans on the back of the TV, so some fan noise is normal. One needs to understand what is normal and what is not.
 
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