Sep 27, 2006 05:22 pm i'm no expert, but i'd say that would definately be 18db's under full scale digital....i'd copy and paste it at gearslutz, they'll prolly be more insightfull than i, or i could if you're so inclined.
broadcast limiting
Posted on Sep 27, 2006 05:10 pm
fortymile
Member Since: Jan 18, 2003
fox news just screwed up and played, for a few seconds, one of the 'standby' feeds--colorbars on hold for incoming video. it said:
fox news
-18dBf
and then some other crap
what does the -18dBf thing mean? i was talking to a friend who's making a film soon about sound for film and broadcast, and i was explaining how limiters set a ceiling appropriate for broadcast. i said it was probably close to zero db. and i said that when those 'annoyingly loud' commercials sometimes come on cable channels, that those commercials are using a different, louder limiting scheme than the network programming is.
how wrong am i about all this stuff? does the -18Dbf mean that the fox ceiling for limiting is -18 db? or am i way off with this? i've been wondering about this ever since i began noticing these volume fluctuations on cable between certain commercials...
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Sep 27, 2006 05:22 pm i'm no expert, but i'd say that would definately be 18db's under full scale digital....i'd copy and paste it at gearslutz, they'll prolly be more insightfull than i, or i could if you're so inclined.
Sep 27, 2006 10:47 pm 0 dBf Preferred informal abbreviation of the official dB (fW); a power reference point equal to 1 femtowatt, i.e., 10^-15 watts.
Sep 28, 2006 06:18 am man, just tell me what it means and what they's doin!
lol
Sep 28, 2006 03:44 pm but I did :)
They're turning down their audio acrrier signal so they don't melt circuits in the studio or clip or over modulate the audio carrier which would sic the FCC on them...
Sep 28, 2006 09:15 pm so that means they're ... what, working below zero db right? just trying to figure out how things compare here....
Sep 29, 2006 01:41 pm yeah, because of they clip they could get fined or worse damage their equipment...which could also lead to fines for not staying on the air...
Sep 29, 2006 07:33 pm As for the commercials being absurdly loud. It isnt becuase it is louder volume wise. It is becuase they compress the living hell out of them. They compress them to the maximum limit. This gives the illusion of them actually being louder, when in reality they are not.
There is a new commercial out playing up here that has takin it another step further with the new MultiBand compresion. They have got the bass slamming so hard it actually make smy TV speakers thump and smack. And its not a cheap speaker set up in the TV either. They have it set so the bass and kick slam the speakers real good. I usually hit mute when that one comes on.
Sep 30, 2006 04:18 am yeah, but what about the local commercials that are obsurdily loud? i get 'em alot down here....all the network stuff is the same volume, then theres a local car salesman that's damn near twice the SPL.....i've often wondered about that....i STRUGGLE to compete with 'commercial' levels, yet some A/V guy can get obsurd levels that's twice as hot....sup wit dat?
Sep 30, 2006 04:04 pm clipping only cares about the loudest frequency, so get a multiband brickwall limiter and you can increase all the other frequencies a lot :)
Sep 30, 2006 05:05 pm Yep, you can really jack it up to appear extremly loud. Most of the newer rock and harder albums from the last 4 or 5 years have used that techique to make the Cd seem like it is louder. In reality they are just simply crushing the life out of them. You dont have the nuances in the music that you would with say an orchestra, jazz or acoustic recording as well as other stuff. It just simply sucks the life out of it. Ambient music would sound like crap if they used that technique. Some disco records were like that. They were intended to be played loud in the dance clubs so they cranked the compresion and away they went.
But indeed the new multiband stuff really lets them make everything so much louder.
Your comment on the local commercials is very true, they want you to jump up and notice them so they are extremly loud and obnoxious.
Sep 30, 2006 09:35 pm but that's retarded: it just pisses everyone off. i hit mute several times a night when im watching the science channel after midnight and working here, just so i dont wake the neighbors. and because it HURTS.
yeah, these are two differnet things, huh. i knew compression to the max was happening on these commercials, but i also assumed that if they're going that far, they probably have no qualms about hugging 0 db, either. compress to the max and then limit it as close to max as possible, right?
Sep 30, 2006 11:14 pm Yep, annoying as it may be.
Sep 30, 2006 11:58 pm I like the low budget ad's that boost the living crap out of 1-4 kHz (where the fundamental frequencies of speech lie (ears are most sensitive here apparently)) to make it sound louder and cut through. Its funny haha.
Oct 01, 2006 07:12 am I home improvement store over here in the US called "Menards" does that, they are always a few db louder than anything else and it's fat and nasty sounding...I refuse to shop there for that reason...fortunately there are plenty of other good reasons to hate the place too...
Oct 01, 2006 01:27 pm The best part is the low bidget car commercials here that the guys are out on the lot. The wind is blowing and street traffic and just plain noise. It all gets cranked up when they do that crap. But ya, dB has it right, the old Menards guy was the loudest most annoying voice.
Oct 01, 2006 03:23 pm Quote:
I refuse to shop there for that reason...
heheh, oh man, i'm still gigglin' from that!
i think i'm gonna start judging businesses by their audio!! this is GREAT!....remember those Jared diamond dealers with the chick bealting "THAT'S JARED!!! WOOOOAHHHHHOOOAHH!" everything about that background music, i HATE!
it's not necessarily the production of it, just the damn song...it's way over-the-top energy-wise and has NOTHING to do with jewlery....all it does is be catchy and stick in my head....
F.U. Jared Jewlers!
i remember a really nice jewlery t.v. spot with the necklace beein' put on the shadow of a person....man it was a string arrangement that i LOVED....i can still hear it in my head.....de de de doo de duhh-done-dahh. that's where i'll shop.
and forty, i think they do hyper-compress everything on broadcast networks...but they set the levels (maybe) at -18 and THAT is what the individual (local) station recieves, then the station brings it up after to something closer to 0dbfsd then it hits the antennas (or gets digitally streamed)....but when someone sends a 'homemade' (aka small budget) commercial, THEY don't send it to the station at -18db, and WHO WOULD anyway? so the station is pretty much runnin' on autopilot (audio wise) and they put the local commercial through, it hits their limiters (which are set real close to 0dbfs) and BAM! EVRYTHING LOCAL IS LOUDER!.....
i just pulled that theory outta my ***, but it kinda makes sense. so again, my thesis, is the actual Networks send their stuff out quiet and let the stations 'broadcast limiters' do the work.
ok i posted it up on a mastering forum, let's see what happens.
www.gearslutz.com/board/showthread.php?t=88009
Oct 01, 2006 05:30 pm I think thats the "A Diamond is Forever" ad campaign by De Beers... it was simply supposed to advertise diamonds as a symbol of eternity because at the time De Beers controlled a huge portion of the diamond market so brand association wasn't necessary... just "get americans to buy more diamonds"
Oct 01, 2006 05:35 pm ...and the only local commercials I can't stand are for:
Glassmaster - a windshield replacement place... spoofing the Ernest P. Worrell character... badly..
and
Bathroon Fitter -form fitting covers for bathtubs ... simply because I work home remodeling with my dad and would be terrified to uncover one of those without the proper resperators... I cannot imagine how they meet code...
and the product I hate most is Gutter Topper (et al) because they don't work and make it a pain in the *** to clean the gutters when they do clog...
Oct 01, 2006 05:47 pm our local right wing station 1280AM "The Patriot" has commercials for a local car dealer, can't even remember the name, but the old, frail owner does them, saying all the great stuff they have and he stumbles over his words and speaks very poorly...every time I hear one I figure they MUST do it on purpose cuz it gives them a more "small town" sound or something, but it just makes me laugh...
Oct 01, 2006 05:56 pm i wanna hear examples of some of these atrocities
Oct 01, 2006 08:07 pm Ya, I'll just run an audio out from my TV rig into here and wait for 4 or 5 hours and record ya a couple. :-)
If I have nothing else going on some night I'll patch a cable in here from the cable box and record a couple for ya flame. That'll give me a goo dexcuse to buy one of them wireless remote deals from Cakewalk, then I can just cue it from out in the living room down here.
Oct 01, 2006 08:47 pm the only station I listen to is the college station, and the DJs read the ads... that's amusing enough. Like earlier tonight "Tune in every saturday morning from 10 till noon to hear a.... do I have to say this? *sigh* to hear a tuity fruity assortment *chucke in background* of kids music, fun for all ages. *whisper* I hate you guys"
Oct 02, 2006 01:57 am This thread ended up being way more entertaining than I ever thought it could be!!!
Oct 02, 2006 04:08 pm I didn't think it would carry on this far. It's been happening for years. God knows I've even been party to it doing some commercials for the cheap SOBs out there that wanna get noticed.
Oct 02, 2006 08:09 pm -18 dbFs is a standard calibration measure in broadcast.
Aes-Ebu (US and Europe) have decided that this is the level for audio alignment with test tones in digital transmissions.
dbFs means simply Full scale and is referred to the digital scale, 0 dbFs = digital clip = square wave = horrible sounds, so the international agreement has set this level for average transmission with a 18 dbFs headroom for transients and modulation, keep attention to the fact that when you think about the resolution of your converters (16 bit = 96 dbFs, 24 bit = 144 dbFs, theoric values) you have to think in negative, say we have a converter that give you a 122 db resolution, that means from -122 dbFs to 0 dbFs.
I can tell that is normal to print on tape at a voice level between -18 and -10 dbFs, but for example mastered musical videoclips from great european broadcasters reach 0 dbFs and are lowered in level when put on air.
In the analog world every country or broadcaster in the world had their standards but with digital equipment everything is more simple, less different standards and the AES-EBU digital standard is the most used.
When you prepare a broadcast limiter you know you have a standard at -18 dbFs for static tones but you can go up with the equipment as you like, even if rules do not permit to do this.
Let's say I set my brickwall to stop transients at -6 dbFs and then I multiband-compress my program as I can with my equipment: now I'm sure that I cannot go over -6 dbFs but if I have set the equipment properly I can achieve a great loudness, even if I change dramatically the sound of the original program, for example I can achieve an average program at -12 dbFs with brickwall at -6 dbFs.
A lot of broadcaster, tv stations and radio stations have nothing to do with something like a "conservative approach" in audio treatments: the goal is to reach the highest level in terms of perception at home.
The result is that a lot of stations transmit always at a higher level than was established by AES-EBU and they do often a little trick having advertisement more louder than the average program.
I hope to be clear, my english is not so good...
Andrea
Oct 03, 2006 09:55 pm ok check out the link i posted earlier....it's all makin' sense to me....-18 appears to be a european standard for a digital refrence level, which is a 1k sine wave and it should show at the stated level (-18dbf in your case)...so when you send the video feeds from the media out to broadcast, you make sure you're meeters read the same, so the program material has enough headroom from whatever engineer made it....and THIS is where, small budget guys over compress their stuff, and send it in MUCH hotter, sometimes on purpose (some ppl will hear it better) and sometimes not.....
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