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THE AM BULLETIN BOARD => QSO => Topic started by: flintstone mop on December 21, 2013, 09:44:50 AM



Title: TV Broadcast Audio
Post by: flintstone mop on December 21, 2013, 09:44:50 AM
Maybe there are some techs here that engineer OTR TV stations or cable TV.
I look at a lot of debate type programs from CNN and Fox Cable News.
Before the latest breakthru in audio processing when the debates would get heated and many people on the panel would start talking there would be horrendous distortion in the audio.
It sounded like the mic pre amps in the console were overloading or the console itself.
It appears that most people on-air are using wireless lapel mics. They seemed to be wired about 5yrs ago.
The advancement in processing I hear now is that there is absolutely no distortion no matter how many start talking over each other or speaking loudly.
How is this being controlled now?
Built-in extremely effective limiting of the wireless mic electronics?? or the audio console more tolerant to spikes in the audio with each mic channel having its own processor. ?? OR what??

I doubt if the distortion was coming from the final audio processor inputting audio into a digital TX or fiber optic system or uplink to a satellite provider. It sounded like the wired or wireless mic or console input was overloaded. Typically a broadcast console has so much headroom there is little chance that the output amps of the board would be distorting.
Any thoughts?
Fred


Title: Re: TV Broadcast Audio
Post by: Lou W9LRS on December 23, 2013, 01:09:15 PM
Hi Fred:
Yes, RF is the norm in the studios these days and most with a lav mic. The improvements over the last few years in RF Mic technology is making
 this  possible. Most of what you hear on the air in a normal news show is being done with no audio operator. The new systems have the audio coded to follow the video moves and that includes voice overs, sot etc. So what you put in is what you get( No Mixing).

On the Debate shows or any other production programs, they still use an audio engineer. The New consoles have adopted a third hand in mixing mic's. Some of them have a soft mix adjustment on each mic channel, similar to a Dugan box. It really helps with the JUMP BALL debates and talk shows. In the Digital audio world of HDTV, our audio levels have changed as well. 0 Db is now a -20 on the new scale with peaks up to a -10. Far more headroom. These new digital consoles give us far better DSP audio dynamics as well.

You can still distort it all if you try hard.....and sometimes people do try hard.

73
Lou



Title: Re: TV Broadcast Audio
Post by: flintstone mop on December 24, 2013, 09:19:58 PM
Thanks Lou for the reply.
The distortion heard in the early days must have been a lot of operator error trying to control 5 mics at once, and the older consoles.
Digital doesn't have to overcome noise floors. Probably explains the lower levels now.
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