What is a normal noise floor indoors? at DVinfo.net

Emre Safak · November 11th, 2006, 04:33 PM

I am trying to find a way to make my DVDs sound better, by which I mean to bring clarity to the dialog. I studied some commercial DVDs, and realized that the dialog is always clear no matter how quiet the actors are talking. On my projects, by contrast, sometimes it is difficult to hear the actors when they are shouting, due to noise. Usually this is beyond my control, but I do my best. I judiciously apply noise reduction, but I still can not avoid noise without grotesquely distorting the character of the speech.

Just to put it into numbers, I took some statistics from a kitchen scene. The RMS value of the noise floor is -32dB, whereas the dialog is -19dB (maxing out -0.87dB). In other words, the noise floor is 13dB below the dialog. Is this an acceptable value, or am I shooting in especially bad conditions? I just listen to it and it sounds amateurish, unclear, and I find myself helpless. I considered gating out the noise but that makes the remaining dialog sound noisy. Maybe I should gate out just some of it?

Greg Boston · November 11th, 2006, 05:19 PM

Emre, in those DVD's you were looking at, they use ADR. The actors watch themselves on a monitor in a studio and re-record their lines. Then they use foley to re-create and enhance the environment the actor was in and mix it all together.

That's just a basic explanation, but you get the idea.

-gb-

Emre Safak · November 11th, 2006, 06:17 PM

So they do ADR, as a rule, when shooting in uncontrolled environments?

Ty Ford · November 11th, 2006, 07:29 PM

Some films use ADR, but if you're regularly having that little distance between the noise floor and the dialog, something is not right. What sort of noise are you encountering?

Ty Ford

Emre Safak · November 11th, 2006, 08:04 PM

Just the city hum.

Steve Leverich · November 11th, 2006, 09:16 PM

If it's something that could work for you, I get a LOT less room tone/outside noise interference using a Sennheiser G2 with a Tram directional lav - haven't actually measured the diff, but seems like at least 6-8 dB, maybe more. This is true whether using in-camera mic or Rode Video mic or AT 897... Steve

Ty Ford · November 11th, 2006, 10:06 PM

Quote:

Originally Posted by Emre Safak

Just the city hum.

get the mic closer to the talent. it should be no more than 2 feet and preferrably within 18 inches of the mouth.

Your mic is OK, but there are better ones; Sanken CS3e shotgun and cmc641 for supercardioid.

Even in exteriors, the Schoeps can be better if the environment is noisy from many directions because it is more directional than a shotgun.

Regards,

Ty Ford

November 11th, 2006, 04:33 PM	#1
Emre Safak Trustee Join Date: Feb 2004 Location: Brookline, MA Posts: 1,447	What is a normal noise floor indoors? I am trying to find a way to make my DVDs sound better, by which I mean to bring clarity to the dialog. I studied some commercial DVDs, and realized that the dialog is always clear no matter how quiet the actors are talking. On my projects, by contrast, sometimes it is difficult to hear the actors when they are shouting, due to noise. Usually this is beyond my control, but I do my best. I judiciously apply noise reduction, but I still can not avoid noise without grotesquely distorting the character of the speech. Just to put it into numbers, I took some statistics from a kitchen scene. The RMS value of the noise floor is -32dB, whereas the dialog is -19dB (maxing out -0.87dB). In other words, the noise floor is 13dB below the dialog. Is this an acceptable value, or am I shooting in especially bad conditions? I just listen to it and it sounds amateurish, unclear, and I find myself helpless. I considered gating out the noise but that makes the remaining dialog sound noisy. Maybe I should gate out just some of it?

November 11th, 2006, 07:29 PM	#4
Ty Ford Inner Circle Join Date: Nov 2004 Location: Baltimore, MD USA Posts: 2,337	Some films use ADR, but if you're regularly having that little distance between the noise floor and the dialog, something is not right. What sort of noise are you encountering? Ty Ford __________________ Ty Ford's Audio Bootcamp Field Guide Ty Ford's Audio Video Blog

November 11th, 2006, 05:19 PM	#2
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	Emre, in those DVD's you were looking at, they use ADR. The actors watch themselves on a monitor in a studio and re-record their lines. Then they use foley to re-create and enhance the environment the actor was in and mix it all together. That's just a basic explanation, but you get the idea. -gb-

November 11th, 2006, 06:17 PM	#3
Emre Safak Trustee Join Date: Feb 2004 Location: Brookline, MA Posts: 1,447	So they do ADR, as a rule, when shooting in uncontrolled environments?

November 11th, 2006, 08:04 PM	#5
Emre Safak Trustee Join Date: Feb 2004 Location: Brookline, MA Posts: 1,447	Just the city hum.

November 11th, 2006, 09:16 PM	#6
Steve Leverich Regular Crew Join Date: Sep 2006 Location: Albany Oregon Posts: 173	If it's something that could work for you, I get a LOT less room tone/outside noise interference using a Sennheiser G2 with a Tram directional lav - haven't actually measured the diff, but seems like at least 6-8 dB, maybe more. This is true whether using in-camera mic or Rode Video mic or AT 897... Steve