Field Recording

IMG_20180401_115009.jpg

I like recording the sounds of nature, and when I play my recordings back, I want them to sound exactly like when I was there. Here is my technique, equipment, and settings I use.

Last updated: 26-May-2018

The Technique, Equipment, and Settings

This effect of “being there” is achieved through binaural recording. Binaural recording, simply and for my purposes, is recording sound with two microphones separated by a human head. By doing this, you get an authentic reproduction of the sound as if your ears were hearing it.

Equipment – Microphones

To get high-quality sound, I use a binaural ear set-up as shown below.

IMG_20180401_115027

Soundprofessionals #MS-MINI-BINAURAL-EARS

miniE-freq-resp

Mini-Ears Frequency Response Curve

The mini binaural ears need microphone power so I turn on the power option within my recorder and these high-sensitivity microphones really give a true binaural experience.

Wind protection is a real thing and must be considered. You will have lots of wind noise to edit if you do not cover the ears/microphones with a furry cover during even the slightest windy weather. Yes, you give up some sensitivity to lower level noises, but I find it is better to prevent the wind noise if possible instead of editing it out later.

I also have a set of headphones that, instead of playing the sound back to my ears, record sounds through tiny microphones located where the headphone speakers would normally be. The microphones are pointed outward and away from my ears. They are model/part #ISI-HMA-1 available from SoundProfessionals.  I have used this binaural headset without the amplifier, and it seems to work o.k. although amplified may be better. Whenever possible though, I opt for using the mini binaural ears.

Equipment – Recorders

The recorders that I use are a Tascam DR-08 and a Tascam DR-05. They are both compacts with built-in binaural recording capabilities. The microphones are separated to achieve that stereo (almost binaural) sound effect of “being there” and the recorders can be taken almost anywhere in my shirt or coat pocket.

They record onto micro-SD cards and have inputs for USB transfer of files. They can record files in the WAV or MP3 format. I usually record in WAV format. I record without equalization and with the sensitivity set to high. For loud sounds, I would probably need to adjust the sensitivity to low, but I haven’t encountered that yet in my recording of nature sounds.

I use a Tascam battery pack in order to get a longer record time and not have to change batteries very often. You can see it attached to the back of my recorder and connected through the USB.

I also use a tripod for holding the recorder and microphones steady during the recording process. This can be any tripod that is steady and does not make noise. I have found that the smaller, lighter tripods do not work well because they make noise. Mine is a MeFoto brand, but any sturdy one will work.

IMG_20180401_115002

DR-05 recorder with ears. The battery pack is behind the recorder and plugged in via the USB on the side. The battery pack is attached to the recorder via the 1/4″ screw on the back. The battery pack is attached to the tripod via the 1/4″ screw on its back.

The DR-05 allows level setting, and I use that whenever I can. This is accessed when the recorder is on standby. I adjust the recording level input to 90 (max) then use the Peak Reduction function during the standby recording. By doing this, the level is automatically set to the highest that does not distort. This setting is retained after recording. If I record a thunderstorm, for example, the peak level from the first thunder will set the max level to the point it will not distort and maintain that level throughout the recording. If a louder noise occurs later, the level will again be set lower to accommodate that peak level. I shoot for a -12dB level on the meter in the recorder. While on standby record mode, the microphones are taking in the sound and showing me the level on the meter so I can manually adjust the level. I usually end up with about a 70% setting on the input. Then during recording, if I have misjudged the level, the peak reduction feature will bring that record level down if needed.

IMG_20180407_071346.jpg

The only problem can come in if I get an abnormally loud noise after setting the microphone and walking away (door slam, dog bark, etc.), but these are not really preventable.

The DR-05 also allows for peak limiting with the Limiter setting instead of the Peak Reduction. I rarely use the Limiter. The idea is to adjust the recording level to where the average sounds hover around the -12dB mark on the display, then if an excessive level comes in, it will be limited by the Limiter.

The third automatic level setting on the DR-05 is the Auto Level setting. Using this instead of Limiter or Peak Reduction moves the recording levels up and down based on the incoming sounds. This can be good for some instances but will produce abnormally high lows and unusually-low highs so this can ruin the realism of natural sound recordings so I do not use it often. When I am recording industrial sounds of varying amplitude where realism is not expected, I use this setting, It is best suited for recording conversations and meetings.

IMG_20180407_071136.jpg

As for the sampling rate ( the speed at which data is recorded during an audio recording), I use uncompressed wave file types recorded at 44.1 kHz. Later I can manipulate the sound data to my liking and these uncompressed files allow a lot of room for editing.

Bitrate I set at 16 bits. This covers 96dB of range and is enough for field recordings that are usually with some noise in the background and do not need the 24 bit. In general, the 24 bit makes little or no difference but increases the file sizes. So, I keep it at 16 bits for quality and storage. I can always upsample later, but this does not offer an advantage in sound quality.

To make recordings, I put my recorder in a sheltered (from wind and rain/snow) area outdoors, push the record button and step away until my watch says it is time to come back and shut it off. I get about 25 minutes worth of recording time for any particular sound.

If I go beyond the 25-minute mark and don’t come back to the recorder to stop it, it continues recording into a different file. Basically, it keeps recording until I stop it and if I go for an hour, it will record two files, one after another.

Invariably there are unwanted noises on the resulting file that have to be removed and I do that afterward in software.

IMG_20180401_114934

My recording set-up positioned behind a small building to protect it from the wind. The sound of wind across the ears during recording is just like across real ears and produces an unwanted noise.

Capturing sounds with my Tascam DR-05. 🎤 #tascam #sounds #recording

A post shared by Lars Lentz (@larslentzphotography) on

For editing, I have two recommendations.

  1. I use the free Audacity software. It takes some getting used to, but this software really works well for editing audio files. Clipping out offending noises is easy, and fade-in and fade-out functions work well.
  2. I also use the relatively low-cost ($99 on sale, $149 otherwise) Izotope RX software. It is a standalone editor that in the Elements version has the basics needed for processing. It facilitates much quicker file editing and makes short work of my file editing.

Editing tips:

Processing Field Recordings Using Absentia DX and Izotope RX

Equalizing Field Recordings

Conclusion

That is how it is done, by me, using my set-up. There are many other choices available out there, but I chose this one as a low-cost alternative to other more expensive set-ups. You can do the same and achieve similar quality files by following these guidelines.

Additional resources are available at these helpful links:
FACT Magazine’s “A Beginner’s Guide To… Field Recording” by Lawrence English

Advertisements