Field Recording

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I like recording ambient sounds of nature, locations, equipment, and other assorted noises. 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: 02-August-2021

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 or reasonable facsimile. By doing this, when you play it back you get an authentic reproduction of the sound as if your ears were hearing it in real time.

Equipment – Microphones

To get high-quality sound, I use either

  1. a mini-ears (fake ears) binaural set-up as shown below, or
  2. in-ear binaural microphones that I wear in my own ears.
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Soundprofessionals #MS-MINI-BINAURAL-EARS
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Mini-Ears and In-Ear Binaural Microphones Frequency Response Curve (same curve for both)

The binaural “mini-ears” I use are from SoundProfessionals and are model number B-15029. They are realistic but fake ears that have microphones embedded down inside of them to simulate a head. They are more portable than a full head system and record great binaural sound. I like to use these for when I can put them on a tripod and leave them outside in the environment. For indoors, they draw too much attention. I use these when I don’t have the ability to be still enough or don’t have the time to spend sitting and recording.

The in-ear, worn, microphones are also from SoundProfessionals. You wear these and they are inconspicuous as it looks like you are listening instead of recording. People don’t know you’re recording, so everyone acts naturally around you and do not ask questions of you. These microphones are from SoundProfessionals and are model number 30-11847 (C7-XLR) – MS-TFB-2-11847. With these, I can record the ambiance of an area without drawing attention to myself much at all.

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Power is needed to activate these microphones. The mini binaural ears and in-ear microphones need 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.

The in-ear microphones have little foam pieces that go over the microphones and then into your ear, but I sometimes find this annoying and impractical when I want to respond quickly and record something. In many cases I use a product called Windfree that is like a set of earmuffs, but without the fur. It allows sound to come through it nearly unimpeded.

Equipment – Recorders

The recorder that I use is a Tascam DR-05. The recorder can be taken almost anywhere in my shirt, pants, or coat pockets.

Manuals:  6L_DR-05_OM_vD and e_dr-05_rm_va

It records onto micro-SD cards and has inputs for USB transfer of files. I 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.

When recording outdoors with a tripod, I use a Tascam BP6-AA battery pack that I bought from BH Photo 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 use this only when on the tripod outdoors with the mini-ears because indoors or for portable use with the in-ear microphones, it is too large to carry easily.

Outdoors with the mini-ears, I 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.

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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.

For “set it and forget it” kind of sounds where I don’t know for sure what I’m going to get, 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. The only thing to watch out for is when setting it up so that you do not inadvertently bump the microphone or otherwise cause a high signal. If you do, then the peak reduction function of the recorder will make all the sound recorded after that event a low level, resulting in disappointing results.

Or, if I have the in-ear microphones in my ears and am listening to what I am to record, 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 adjust for an average level of -12 dB as indicated on the recorder’s display while in standby recording mode. I keep the Peak Reduction function active, then during recording so that if I have misjudged the level, the peak reduction feature will bring the recording level down if needed.

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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.

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As for the file format, bits per sample, and sampling rate, I use uncompressed, 24-bit wave file types recorded at 44.1 kHz.

File type I set as Wave (WAV).

  • It is an uncompressed format so I am not losing any information in compression.
  • It is supported by many software clients including Microsoft and Apple.
  • Files can be manipulated from Wave into other formats as needed. I like the FLAC format and often convert my final files from Wave to FLAC in 24-bit format.

Bit per Sample I set at 24 bits.

  • I used to use 16 bits as this covers 93-96dB of range and seemed to be enough for field recordings that are usually with some noise in the background and maybe do not need the 24 bit.
  • But, I was wrong. I have found with my recordings that I lack the “air” sound in my 16-bit recordings where my 24-bit ones have an “airy feel” that I like.
    24-bit is definitely better.

     

    • This is probably because the noise floor is much lower in 24-bit recordings.
    • The dynamic range is increased.
    • There are 65,536 possible levels in 16-bit recordings, where 24-bit ones have a whopping 16,777,216 levels. This additional detail in 24-bit recordings is noticeable to me.
    • Several professionals support 24-bit recording.

Sampling Rate I set at 44.1 kHz.

  • My output medium is CD-quality and CDs only support the 44.1 kHz rate.
  • To record at higher sampling rates means more data, but ultimately useless data because I have to downsample to 44.1 kHz in order to get to CD-quality.
  • Downsampling from 96 kHz or 48 kHz to 44.1 kHz can cause errors that are audible in the final output.
  • Several professionals support 44.1 kHz sampling.

To make recordings outdoors with mini-ears, I put my recorder and mini-ears 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.

To make recordings indoors or outdoors with in-ear microphones, I put the microphones in my ears and the recorder in my pocket then place myself where I want to record. I record anywhere from a few minutes to a half hour of sound in-location. I like to capture what it feels like to be there so I may turn my head occasionally to get a different perspective. I might record this as a separate file or just keep recording one file.

Here is an example of an in-ear binaural recording taken from inside a parked car facing a busy roadway with the windows down.

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

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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.

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 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.
  3. Becoming more of my favorite is Edison from Image-Line and found within FL Studio. This one is great for making seamless loops.

In the end, I use a combination of two or more of the above.

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