Questions & Answers:
Plasma & LCD Screens
Plasma & LCD Screens
How bright does my plasma need to be?
Are Plasma Screens silent?
Plasma TV buzzing
How long my plasma last and can it be “recharged” / ”regassed”?
Will I suffer screen burn on my plasma or LCD?
Do I need a tuner?
Do I need a tilting wall-mount?
How bright does my plasma need to be?
Plasma brightness figures are a bit of a lost cause. It is virtually impossible to gain any sort of idea of how the plasma will look based on this number! The only way to know is to look for yourself!
Are Plasma Screens silent?
In short, Yes. Plasma screens are made up of electrical circuits and as such these will make a buzzing noise much like any other electrical device would! Realistically speaking any buzz is no louder than the sound of a DVD spinning, a transformer buzzing, or an amp clicking, and is practically inaudible unless the rest of the room is silent.

The other type of noise you may be able to hear is fan noise. Again this is usually much lower than that which is audible over a soundtrack and is hardly an issue. 9 out of 10 42” plasmas do not have fans at all (fans tend to be on high resolution models only) and those that do run at low speed while there is a picture on screen, and only run louder on start-up and shut-down
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Plasma TV Buzzing

Plasma panel buzz is a normal phenomenon. Plasmas work on a totally different principle to colour televisions and have different operating characteristics. The level at which the operating buzz becomes noticeable is always subjective; one person may hear it whilst another does not. The following points help to understand the factors surrounding the buzzing:

The picture scanning drive circuits operate at high frequencies and powers. It is these circuits that cause the buzzing sound. The circuits are used to create both the picture and reuse energy to keep the unit efficiency high and panel heat emission low. This over-heating control is very important on the panels that do not use fans i.e. 37” and 42”. The resulting loss of fans makes for a quieter panel operation.

Due to the very high amount of power processing required, the 50” panels have cooling fans (up to 4), which will also contribute to the overall noise these plasma panels will produce. The buzz will appear more concentrated at the sides of the unit where the power circuit boards are situated.

Where cooling fans are not employed, the buzz may be heard in very quiet surroundings. Plasma buzzing is normal and will always occur, but the level of buzz is what matters.

Generally speaking the buzz will only be heard in quiet surroundings (with low levels of audio from whatever sound system used) and with the userseated too close to the panel - less than 12’ for 42” and 10’ for 37” panels.

A typical scenario is using the panel in the middle of the night when listening to news broadcasts at low volume. In this situation buzz might be heard during the silent breaks in the audio, but not so much during speech. This is not abnormal nor does it indicate a faulty panel.

If the buzz is heard above normal ambient daytime noise and audio levels at more that 12’ a problem might be present.

The method of panel installation will also affect the amount of noise heard. Wall mounting the panel will cause buzz emitted from the back of the panel to be reflected off the wall and into the room more than if the unit is located on the pedestal which is seated 2 to 4 feet away.

Plasma panels do not run in total silence. They do buzz as a normal part of their operation, but this level of buzz is quite low and may beintermittently noticed in quiet surroundings, many factors can influence this.

Changing the picture mode in the picture settings menu between dynamic/normal/cinema will also reduce the level of perceived noise since this affects how much power the panel is processing and this the level of power produced.

Having too much brightness and contrast with the dynamic mode setting on,can overdrive the panel and cause louder buzz levels with strong picture signals i.e. DVD or Sky digital signals. Changing these settings can lower the level of buzz produced. Use ‘normal’ picture mode and lower brightness/contrast settings to reduce this effect.

It is normal for the buzz tone and level to change the picture content because the panel drive circuits are processing different amounts of power and adapting their drive cycles.

Hard wall surface i.e. painted/wooden panels will be more effective reflectors than say walls that are covered in softer finishes, wall papered or curtained.

Please ensure these facts are understood and check your panel against a dealers display unit before requesting service, since abnormal levels of buzz are not always ‘abnormal’ but just the normal operating buzz of plasma technology.
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How long my plasma last and can it be “recharged” / ”regassed”?
Recharging of plasmas is an urban myth at best. There again, the plasma won’t show any visible signs of losing image strength until about 30,000 hours use which even at 6 hours a day 7 days a week would take 13 years!!! The latest generation of plasmas are capable of 50,000 hours use…
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Will I suffer screen burn on my plasma or LCD?
LCDs are far less susceptible; in fact it is practically non-existent. Plasmas though use phosphors to generate the image; a still image burned onto phosphors over a period of time can become permanent. E.g. if you left a still image on your plasma for several hours quite a chunk of it would still be there ghosted into the background by morning. Thankfully many plasma screens have built in screensavers as a preventative measure, and “image reversal” mode, which allows you to try removing any residual image.

In most home environments, the material displayed on the plasma is constantly changing (i.e. the screen is showing moving video rather than fixed slides or advertising screens as in a commercial environment) and plasmas are becoming more resistant to burn anyway (the Panasonic is notably good on this front). It has got to such a point where except for the first 100 or 200 hours use where the plasma is more susceptible, you can almost forget about burn-in altogether!
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Do I need a tuner?
A tuner in the literal sense of the word refers to a chipset that can “tune” into analogue or digital signals and output them in a format that your screen understands. In the context of specific plasma and LCD televisions the media box containing the inputs, buttons and tuning chip is often (incorrectly) referred to as a “tuner”. So this question has two parts: 1. Do I need a tuner to tune into TV signals? In which case the answer is yes unless you have Sky TV, Freeview etc to send pictures to the plasma instead. 2. Do I need a media-box to connect all my stuff too? In many cases the media-box is the easiest way to do this and may offer other advantages such as teletext or picture in picture, but it is sometimes far easier (or better quality) to run your sources direct to your plasma using various cables, switchers and signal converters available from our site
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Do I need a tilting wall-mount?
Usually no. It is very tempting to place your plasma high on show (maybe above the fireplace) with a 5-10 degree tilt aiming down at where you audience will sit. However, this tilting does nothing to remedy the fact that the plasma is still too high in the first place which invariably leads to you receiving a creak in the neck! Given that most plasmas have a 180-degree viewing angle, tilting still wouldn’t offer any real advantages unless the plasma was installed at a completely out-of-reach position (e.g. above doorframe)!! In short, think twice about plasma positioning – if you think you need a tilting mount it may be that your plasma is already too high…

(many of our customers cut out a piece of cardboard to the size of their plasma and experiment with positioning using this – may be crude but works a treat!)
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