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How to record sound effects clean without noise

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BasRonin:
Hello all,

Im a beginning sound recorder, and have just started because i make shortmovies and want to have clean audio with this.

I bought myself a Tascam dr-70d and a Rode NTG-4 as main setup.

I have learned to record with peaking around -12db, and in post editting with Audicity getting this peak to max 0db.
With conversation dialogues, this works perfect, but...

When i want to record sound effects, for example a pencil scraping on a paper, i cant get to -12db with my recorder and shotgun mic because of the low sound effect. I can put the Tascam dr-70d to high-+ mode but then the white noise in the background gets very very loud which is not the clean sound im looking for.
For ‘the record’, im recording those effects with the Rode NTG-4 as close on the pencil as possible.

I can imagine nature documentaire filmers who record environmental sounds in the nature cant get close to -12db as well with sounds from screaming birds in the far distance..

Im very curious how you guys record low noise sound effects with your sound recorder and shotgun mic combo and im wondering if u guys try to record these effects around -12db also or if there are other rules about recording non-dialogue sound effects.

Thanks in advance.

opsopcopolis:
This isn't necessarily the right place for a question like this, as most people here are hobbies concert recorders. That being said, what bit depth/sample rate are you recording at? If you're at 16 bit you may want to try bumping that up to 24, as I've found the noise floor to be quite high on those tascams at 16.

The answer to your "how to pros get such clean recordings" question is almost definitely that they spend thousands on gear. The sounddevices decks are well known for having a stellar noise floor and are generally the industry standard for location stuff.

Gutbucket:
A low noise-floor is critical for recording very quiet ambient stuff.  Getting your recording levels peaking close to -12dBFS is not.

The issue becomes determining what is dominating the noise-floor of your recording chain.  It could be the noise of the environment in which you are recording - the room's noise-floor.  It could be the self-noise of the microphone itself (specs on that Rode lists- Equivalent Noise Level (A-weighted) of 16dB-A) < that's fine for most music recording but a bit noisy for really quiet ambience and whisper-quiet sound effects.  Or it could be the input noise-floor of the Tascam recorder.

If it's the room (and it easily could be), you need to quiet all sources (close the windows tight, turn off the A/C, unplug the fridge, etc) or record somewhere else that is quieter.  If is the microphone's self-noise you'll need a microphone with a lower self-noise specification.  If it's the recorder's input stage you could use a microphone with higher sensitivity which would have a hotter output, use a preamp in front of the Tascam that has with better input noise-specs (a lower Equivalent Input Noise specification) to provide the required gain prior to the recorder, or switch to a different recorder with lower EIN specs.

Some useful links-
http://www.neumann.com/homestudio/en/what-is-self-noise-or-equivalent-noise-level

Check wildlife recording forums and sites for recommendations such as-
https://www.wildlife-sound.org/ and http://www.avisoft.com/

kuba e:
I also do not record ambient sounds, but one thing figured me. When recording extreme quiet sounds, it's good to be as close as possible to the source to being louder than the background noise and to have higher output. You aren't close to the sound source with the shotgun mic because there is an interference tube and the mic capsule is in the opposite end of the tube.
Dr-70d has internal microphones. Maybe you could try them out. These internal microphones are not bad for recording ambient sounds. You could make a recording with one internal microphone that will be placed as close as possible to the sound source. Then compare it to the shotgun. If your internal microphone gives you better results than the shotgun, then you can buy some small electret external microphone and you will have the freedom to place it anywhere.

Gutbucket nicely described the theory. It's also useful for me, thank you. But as Opsopcopolis wrote, they will give you practical advice in a film forum or an ambient recording forum. I have seen only few posts about ambience recording here.

splumer:

--- Quote from: BasRonin on March 04, 2018, 02:20:42 PM ---
When i want to record sound effects, for example a pencil scraping on a paper, i cant get to -12db with my recorder and shotgun mic because of the low sound effect. I can put the Tascam dr-70d to high-+ mode but then the white noise in the background gets very very loud which is not the clean sound im looking for.


--- End quote ---

I've done Foley recording before ("Foley" is what recording sound effects is called), and some sound effects are simply too difficult to record. In this case, it's so quiet, that even in a soundproof booth, the sound effect itself might not be loud enough to overcome any system noise that you'll have in your recording setup. The solution is to not record that particular sound, but something that's louder and easier to capture that could stand in for it. A stick on sandpaper, maybe? Experiment until you find something you like. Foley artists do that all the time; that's where the "art" comes in.

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