Those of us who work in the sub-terranian world of sound post-production are an observant lot - for instance, we've noticed that recently the shape of the television picture has changed. Yes, it's true - virtually all broadcast television produced today is in 16x9 widescreen.

Admittedly, this fact has been largely kept from the general public, probably to avoid panic in the streets. (Your friendly neighbourhood appliance store will still happlily sell you a large-screen 4x3 TV, whilst neglecting to tell you that very soon it will be about as useful as an ashtray on a motorbike.)

But, why venture to the Dark Side and concern ourselves with pictures at all? I must admit, I was becoming quite fond of the tall and stretchy pictures on my old 4x3 studio monitor, but that might just be the medication.....

The fact is, we often have to share our working space with other life-forms - Directors, Producers, Network Heads of Production, and small insects who are just attracted by the bright flashing lights.

Another Little-Known-Fact is that, sometimes, the sound mix is the first time the client has seen their production in all its highly-polished, colour-graded glory.

So, whether we like it or not, we need a screen in our mixing studio that has the "WOW" factor.

At first glance, the new generation of plasma screens seem to be the perfect solution. They're big, they're flat, they're widescreen, they're expensive, they hang on the wall, and they look pretty darn sexy. Furthermore, they don't generate that annoying 15,625 KHz whistle that CRT's have always done, and they don't interfere with speaker placement nearly as much as a big, fat CRT box will do.

However, as this correspondent has recently discovered, they do pose some problems in the sound post-production environment. The first, and probably most serious, is lip-sync. It's hard to get a definitive answer from plasma display manufacturers, but it appears that most plasma screens have a built-in delay of at least one frame.

One model we tried had a delay of about three frames (120 mS). Upon placing the rep in a headlock, we finally got an admission that, yes, they do have a delay of 40 mS (one frame). They could not explain, or even admit to, the three frame delay, observed on two seperate units. We have referred the rep to Donald Rumsfeldt's interrogation squad, and await a reply. Those electrodes on the genitals can work wonders.

It appears that one possible cause for the delay is the fact that plasma displays use progressive scan, like a computer monitor, rather than interlace, like a conventional TV. So, in order to display a normal interlaced video signal, the plasma display has to store each pair of fields and then display them as a progressive frame. This takes at least one frame to achieve. That would appear to be an inherent design characteristic, and doesn't seem to have any easy fix.

There are also other processes going on in the plasma display that can introduce delays.

The dealers helpfully suggested that all we had to do was insert a corresponding delay in our audio monitoring, and all would be well. Well, yes. We could turn the monitoring level up to make the programme sound louder as well, but is that really the answer? This would appear to be approaching the problem from the wrong end, and could create more problems than it solved. For a start, how do you deal with the echo in an artist's headphones when recording ADR with open talkback? And what about 5.1? Do we use six identical delays, all perfectly matched and phased? A career in radio is starting to look attractive....

Another unexected issue with plasma screens is the burn-in. All through the User's Manual are dire warnings about what will happen if you leave a freeze-frame, logo, or any static image up on the screen for an extended period. It seems that they burn-in. In other words, the screen acquires a permanent image of whatever it was, which, by the way, voids the warranty.

Excuse me, but don't sound editors and mixers need to work with a time-code window displayed at all times? And won't that burn in to the screen in next to no time?

Well, yes, actually.

Hmmm.

To be fair, plasma screen technology is still in its infancy, and no doubt these problems will be solved as time goes by. How soon depends on how pissed-off the consumer at home gets when he plugs in his brand-new Home Theatre System and finds that everything looks like a badly-dubbed martial arts film, or wakes up in the morning to find last night's DVD menu permanently burned into his $10,000 screen.

Watch this space.

The Masked Mixer works in a Sydney sound post-production studio. He likes wind-surfing, horse-riding, and meeting people. Not that he has ever done any of them. He got into the business because he was attracted to the bright flashing lights.

©ASSG 2003