Topic: Room noise?

[Hank H.]

Hi,
I'm recording speech for radio broadcasts. I'm pretty satisfied with my combination of the Sennheiser MD 421 and the Marantz PMD 661 MkII - it's very low-noise. But still, when I record people with quiet voices and normalize them afterwards, sometimes noise/hiss is clearly noticeable. Not a big issue, but still annoying from a perfectionist's point of view. Does this also depend on the room I'm recording in? I'm talking about quiet rooms without computer fans, air conditioning etc., but not studio environments, e.g. offices which have some reverb. Is there such a thing as "room-inherent noise" which gets recorded (besides the obvious reverb)?

[aaronji]

Yes, there will always be some level of ambient noise... 

[anr]

http://www.engineeringtoolbox.com/nc-noise-criterion-d_725.html

[ScoobieKW]

There are things you can do to mitigate ambient noise during post production.

iZotope RX does well at removing not only constant noises but sudden transients as well.

[Hank H.]

There are things you can do to mitigate ambient noise during post production.

iZotope RX does well at removing not only constant noises but sudden transients as well.

Thanks for that. Sounds promising. I'm not going to spend 350 dollars on it, though. But I'll probably download the trial-version.

I was just curious whether this comes only from my equipment or also from the room, since I had the impression the noise/hiss is not always present in the same way.

[2manyrocks]

I have a suspicion that the process of normalizing the audio to bring it up to a useable level is where you are getting your hiss.  If someone is speaking in a low voice, you need to be particularly careful to make sure you record with adequate gain in the first place, make every effort to get them to speak directly into the mic, and try to get them to speak up.  If you record at a low level and then try to boost it, you're going to get hiss. 

You can't record what isn't there in the first place.  If they are intimidated about speaking up, find a way to encourage them to speak up.   

[ilduclo]

if you can, record in 24 bit and then the amplification will add less hiss

[thunderbolt]

For interviews/radio stuff, I use my Oade-modded PMD661 with an EV RE-50 D/B, an AT4073 shotgun, and a VP-88.  The VP-88 is considered a rather "noisy" mic, but if you give it a clean preamp, it can sound really good.

I wonder if it may be the the stock Marantz preamp that is contributing to some of the perceived "noise."  Try recording something in 24-bit in a really quiet room, and it should tell you whether it's the stock preamp or not.  The Oade mod was definitely worth it for me.