Quick question on audio levels for mixing an event DVD at DVinfo.net

Go Back   DV Info Net > The Tools of DV and HD Production > All Things Audio

All Things Audio
Everything Audio, from acquisition to postproduction.


Reply
 
Thread Tools Search this Thread
Old April 4th, 2006, 01:19 PM   #1
Trustee
 
Join Date: Aug 2003
Posts: 1,483
Quick question on audio levels for mixing an event DVD

Hi, I make event DVDs for playing on
all types of home TV sets.
There's spoken word and music.

I've been having my levels average about -9dB
and keeping in the range of going up 6dB (to -3) and
and down 6dB to -15.

I'm tired of the effects of heavy compression and
limiting and was considering shooting for an average
of -12dB, and keeping in the range of up 9 and down 9,
so keeping levels between -3db and -21dB.

Do you think the levels would end up being too low.
Someone here menioned that TV programming is
usually kept in the area of 3dB up and 3dB down.

Last edited by Dave Largent; April 4th, 2006 at 02:22 PM.
Dave Largent is offline   Reply With Quote
Old April 4th, 2006, 03:24 PM   #2
Inner Circle
 
Join Date: Jan 2003
Location: Chicago, IL
Posts: 6,609
Dave,
Peaks on DV should be around -12db (equals 0db in analoge)- I try to keep my average around -15 or so but most importantly I work at keeping peak at-12. At most of the seminars I do that's generally fairly easy to do it's the DJs and bands at receptions that play havoc.
Sometimes with the camera set to peak at -12 the average drops to about
-20 and then I have to boost it a bit but I'd rather do that than have to play with compression to try to save a clipped piece. But that's just me!

Don
Don Bloom is offline   Reply With Quote
Old April 4th, 2006, 03:30 PM   #3
 
Join Date: Jan 2004
Location: Stockton, UT
Posts: 5,648
Quote:
Originally Posted by Don Bloom
Dave,
Peaks on DV should be around -12db (equals 0db in analoge)- I try to keep my average around -15 or so but most importantly I work at keeping peak at-12.
Don
Actually, this number is dependent on the gear's calibration, not any baseline spec. This is why the ATSC determined a few years back, that -20dBFS is the equivalent of 0 dBVU.
Content dependent and calibration dependent, -12dB is a reasonable averaging point, but if you've got more than 12dB of dynamic range, this means you're hitting 0dBFS, and unlike analog, you can't go past that point. it truncates/blows up/shatters/brickwalls/whatever you want to call it. Keeping your PEAK at -12dB means you're throwing away a lot of bits.
__________________
Douglas Spotted Eagle/Spot
Author, producer, composer
Certified Sony Vegas Trainer
http://www.vasst.com
Douglas Spotted Eagle is offline   Reply With Quote
Old April 4th, 2006, 03:48 PM   #4
Trustee
 
Join Date: Feb 2004
Location: Brookline, MA
Posts: 1,447
What constitutes a 12dB dynamic range?
Emre Safak is offline   Reply With Quote
Old April 4th, 2006, 04:18 PM   #5
 
Join Date: Jan 2004
Location: Stockton, UT
Posts: 5,648
Measuring from the most quiet point to the loudest point is how dynamic range is determined.
__________________
Douglas Spotted Eagle/Spot
Author, producer, composer
Certified Sony Vegas Trainer
http://www.vasst.com
Douglas Spotted Eagle is offline   Reply With Quote
Old April 4th, 2006, 04:25 PM   #6
Inner Circle
 
Join Date: Jan 2003
Location: Chicago, IL
Posts: 6,609
Hey Spot,
Thanks for the info-I've always looked at -12 as my peak level and try to stay around -15 to -20 for average but now I need to look at that again. But maybe not-you know I've got it going pretty much where I want it now using those levels (took me some time to get them figured out-about 5 years ;-0) so maybe I shouldn't mess with it.

BTW, I don't remember if you were the one who recommended the AKGSE300/C93 hypercaroid - if you were thaks a milion-great sound for indoor run and gun and receptions and such-sounds so much better than the ME66 and the AT897. (if you didn't reco it thanks for all the audio help anyway)

Don
Don Bloom is offline   Reply With Quote
Old April 4th, 2006, 05:26 PM   #7
Fred Retread
 
Join Date: Jul 2004
Location: Hartford, CT
Posts: 1,227
Quote:
Originally Posted by Douglas Spotted Eagle
... -12dB is a reasonable averaging point, but if you've got more than 12dB of dynamic range, this means you're hitting 0dBFS...
I think you must have meant 24dB dynamic range?
__________________
"Nothing in the world can take the place of persistence..." - Calvin Coolidge
"My brain is wired to want to know how other things are wired." - Me
David Ennis is offline   Reply With Quote
Old April 4th, 2006, 05:38 PM   #8
 
Join Date: Jan 2004
Location: Stockton, UT
Posts: 5,648
I could have said that better, sorry.
If your quietest point is at -12dB, and you have say...14dB of dynamic range, you're screwed.
If your average is -12dB, then you have 12dB of dynamic range. Thanks for catching me on that, Fred.
__________________
Douglas Spotted Eagle/Spot
Author, producer, composer
Certified Sony Vegas Trainer
http://www.vasst.com
Douglas Spotted Eagle is offline   Reply With Quote
Old April 4th, 2006, 08:20 PM   #9
Trustee
 
Join Date: Feb 2004
Location: Brookline, MA
Posts: 1,447
Quote:
Originally Posted by Douglas Spotted Eagle
Measuring from the most quiet point to the loudest point is how dynamic range is determined.
I understand that, but I was looking for a real-life example of a situation where you would encounter such dynamic range. Basically I am trying to get a feel for the numbers.
Emre Safak is offline   Reply With Quote
Old April 4th, 2006, 09:47 PM   #10
 
Join Date: Jan 2004
Location: Stockton, UT
Posts: 5,648
depending on the person's speaking voice, you *could* encounter a dynamic of 20dB, if they were passionate or pulpit pounders, and the spoken word contains a lot less dynamic than the singing voice, which is why compressors are all but required in most singing-voice situations and many spoken word situations.
Additionally, you might have two actors with a wide range from the most quiet point of one actor and loudest point of another.
Television has a dynamic range of around 8-10dB, which is better than it was just a few years ago, and getting wider bit by bit (no pun intended). Technology has the ability to provide a lot more range than that, but at the same time...you gotta be careful about how much range you put into something. Walter Murch says he's squeezing 25dB of dynamic into some motion pictures. That's a lotta range! I'd like to be that good and still leave the audience without bleeding ears. :-)
Anyway...recording normal, average dialog expecting around 12dB of dynamic range should be plenty, but as a side tour, this also explains why you need compression, and good compression, for most projects. I'd be seriously in trouble without my UA100 or WAVES tools on the software side, and various compressors on the hardware side.
Somewhat related... This is a great read
__________________
Douglas Spotted Eagle/Spot
Author, producer, composer
Certified Sony Vegas Trainer
http://www.vasst.com
Douglas Spotted Eagle is offline   Reply With Quote
Old April 4th, 2006, 10:06 PM   #11
Regular Crew
 
Join Date: Jan 2006
Posts: 104
For the record -

Classical music usually has much more dynamic range than that. And it's rarely compressed. Requires good equipment for playback, and a lot of skill for recording - and good sound-checking! A soprano has a tremendous range, and a peak can easily jump 30db above averge for lots of pieces!

Percussion, applause, etc. have lots of big peaks, too, but are often forgivable in a way that other sounds aren't; you can sometimes let those go. But listening is the only way to know!
Barry Werger is offline   Reply With Quote
Old April 4th, 2006, 11:06 PM   #12
Regular Crew
 
Join Date: Nov 2005
Location: Okemos, MI
Posts: 174
Sorry, audio newcomer here. How do you impose DVD-appropriate levels on your audio using something like Sound Forge 8.0? Using Normalize (peak or RMS?)? or Dynamics (which settings?).
Patricia Lamm is offline   Reply With Quote
Old April 5th, 2006, 05:11 AM   #13
Inner Circle
 
Join Date: Mar 2005
Location: Hamilton, Ontario, Canada
Posts: 5,742
Quote:
Originally Posted by Patricia Lamm
Sorry, audio newcomer here. How do you impose DVD-appropriate levels on your audio using something like Sound Forge 8.0? Using Normalize (peak or RMS?)? or Dynamics (which settings?).
Normalizing raises the overall gain of the track so the peaks are just below clipping. It's like turning up the volume control. Compressors such as Sound Forge's Dynamics plugin, OTOH, selectively change the gain, raising quiet passages while leaving the loud ones as is. There's no single set of settings that would be universal. It depends on the type of music, etc, and personal taste.

I discovered some "tips and tricks" documentation in the product information section of the Waves web site - www.waves.com - that can help you with starting points for settings to try. Even though they are discussing their own products (which will work with Sound Forge, BTW) those pages can help you understand the principals.
__________________
Good news, Cousins! This week's chocolate ration is 15 grams!
Steve House is offline   Reply With Quote
Old April 5th, 2006, 08:41 AM   #14
Regular Crew
 
Join Date: Nov 2005
Location: Okemos, MI
Posts: 174
Hi Steve, thanks for your answer. I've gone through some books and videos and have a general idea of how to play with normalization and dynamics/compression. I think my confusion at this point is more one of terminology and how to find certain quantities using something like sound forge. When someone says they keep their average levels at -15 dB, are they referring to an RMS of -15 dB over the entire sample? (I know they don't really mean 'average' because that should be -Inf, right?)
Patricia Lamm is offline   Reply With Quote
Old April 5th, 2006, 09:11 AM   #15
 
Join Date: Jan 2004
Location: Stockton, UT
Posts: 5,648
Quote:
Originally Posted by Barry Werger
For the record -

Classical music usually has much more dynamic range than that. And it's rarely compressed. Requires good equipment for playback, and a lot of skill for recording - and good sound-checking! A soprano has a tremendous range, and a peak can easily jump 30db above averge for lots of pieces!

Percussion, applause, etc. have lots of big peaks, too, but are often forgivable in a way that other sounds aren't; you can sometimes let those go. But listening is the only way to know!
Of course it does. But you cannot put uncompressed classical music into a broadcast or into a DVD stream, for the most part. Audiophiles *hate* this, of course, but when mixing/mastering, you've got to consider John Q. Public and not the guy that has top end Martin-Logan, tube or super high end amp/preamp, etc.
I would shudder to think anyone might use a DV camera or HDV camera for primary audio source from an orchestra or symphony....Yuk.
__________________
Douglas Spotted Eagle/Spot
Author, producer, composer
Certified Sony Vegas Trainer
http://www.vasst.com
Douglas Spotted Eagle is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > The Tools of DV and HD Production > All Things Audio

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 03:41 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network