Audio tips

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Binaural audio recording is a unique way of recording sound. By using our binaural microphones, or by using two microphones with pinna, rather than using a stereo pair, and having them mostly equidistant to each other, like your own ears are, you can capture audio that results in a genuinely multi-dimensional listening experience.

​Binaural audio is some of the most immersive and realistic audio experiences available when listened to through headphones.

That all sounds great, but it can be difficult to truly get the most out of your binaural recordings. Here I am going to go through a few helpful tips and tricks I’ve picked up through the years, so you can maximise the quality of your binaural audio!

Optimise Your Recording Settings For Binaural Audio​
The settings you use for your binaural recording are important when it comes to getting the best quality audio.

You should use the best settings possible you can for your binaural recording, for YouTube we recommend the following minimum settings:
  • 16 bit
  • 48kHz
  • WAV or AAC (320kbps)

When it comes to your recording settings, you should also turn off any limiters that you may have on your recorder. This is because it could hinder your binaural recording, unless you are recording in a noisy area that could cause your audio to clip.

Do not use auto levels, this will stop "pumping" effects and spoiling your recordings. Auto levels, also known as automatic gain control (AGC), is a feature in audio recording equipment that automatically adjusts the gain or volume of an audio signal to maintain a consistent level.
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While auto levels can be useful for ensuring consistent recording levels, they can also have drawbacks. For example, in some cases, they can introduce unwanted noise or artefacts into the recording. Additionally, the automatic adjustment of gain can sometimes result in unnatural or inconsistent sound quality, particularly in complex or dynamic recordings.

The pumping effect refers to a change in the volume level of a sound that is caused by a dynamic range compression or limiting effect. When the volume of the sound reaches a certain level, the compressor or limiter kicks in and reduces the volume of the sound, resulting in a "pumping" or fluctuating effect.

Optimise Your Recording Settings For ​Binaural Audio​
We strongly recommend that you do not use MP3 as your file format, this is because it will remove some aspects of the HRTF (head related transfer function) information and be less effective.

The Head-Related Transfer Function (HRTF and ERTF) is a set of filters that characterizes how sound waves from different directions are modified by the head, torso, and external ear before they reach the eardrum. HRTF and ERTF are a vital component of binaural audio, which is used in many applications such as virtual reality, gaming, and spatial audio.
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The HRTF and ERTF is unique to each individual and is influenced by the shape, size, and orientation of their head and ears. It can also be influenced by factors such as age, gender, and the angle of incidence of the sound wave.

For YouTube, we recommend the following audio settings:


Export: AAC, 320 kbps (or higher), 48 kHz, Stereo.

When importing audio into our video editing software, we use the following settings:

Import: 24bit 96kHz WAV (or higher)

For HD sound, please use 24bit (or 32bit float) 192khz WAV (non-video, downloadable files on soundcloud.com for example).

We recommend that your authoring software is using the best audio quality settings it can use for exporting, using WAV, or just use the highest quality audio settings that your recorder used for the recording.
For the very best binaural audio experience, try not to use equalizers or normalising.

Equalizers can potentially interfere with, or enhance in some situations, the accuracy of binaural audio because they alter the frequency response of the sound signal. Binaural audio is designed to simulate the way sound waves interact with the head, ears, and body to create the perception of spatial sound. This simulation relies on the accurate reproduction of the original sound signal, including its frequency content, in order to create a convincing 3D audio experience.

On playback on computers, please switch off any enhancement settings.
Avoid Using Standard Recording Techniques For Binaural Recording

We strongly recommend avoiding adjusting the preamp on your recording device to boost the sound levels of what your recording. ​It will add extra noise that could potentially ruin your recordings as well as having a negative impact on the binaural effect that you are looking to achieve.

A preamp (short for preamplifier) is an electronic circuit that amplifies weak signals from a microphone, instrument or another audio source, to a level that can be processed by a recording device.

In the context of recording, a preamp is typically found on a recording device such as a mixer, audio interface, or standalone preamp unit.

The primary purpose of a preamp is to provide gain or amplification to the audio signal before it is processed by other components in the recording chain.

When recording, make sure that meter levels only bob up and down now and then when in a quiet room, if the meters show above the minimum all the time it's too high, turn it down to the minimum deflection so that it occasionally bobs.


Binaural Recording For Specific ​Recording Devices

Zoom H1n recording settings
For the RCA, DIY Kit, and BASIC ver 2 type, a level set to 5 on the dial is a good setting as it does not boost the recording levels too high for binaural recordings.

Tascam DR40X
Levels set at default at -12db for XLR microphones, this does not boost levels for binaural recordings and are ideal.

Sound devices MixPre 3 or 6
Use gain levels at about 35 to 40db, and headphone output level set to 70.

Playback is just as important as the recording technique, you must keep the levels of audio to a level of what it would be if you were there.

For example if you were to remove your headphones the sound would be the same level as what it was while monitoring the recordings, you should not be able to tell any difference, if it's louder you need to be sure that it is either the recording level, or the headphone volume of the recorder.

​Once you have established the correct levels in both the recording level and the headphone volume level of your recording, then the device is calibrated correctly.

Switch off any effects on your computer's sound card (check playback properties).

Some listeners may think that the levels are a little low, as they maybe used to standard recording/listening habits. When you have realised this technique, you will experience very effective binaural recordings.

Choose The Right Location For Your Binaural Recording
Depending on if you are recording ASMR or field recordings, choose a location that has interesting sounds and is free from extraneous noise, or look for noises that are coming from different directions for field recordings, as these can add an extra dimension to the recording. Ideally for ASMR, the location should have a non-reflective surface, like a small room with a few blankets hung on the walls, this is particularly important if you are looking to record very specific sounds.

Obviously, if you are aiming to capture the sounds of an outdoor environment, these factors don’t need to be taken into consideration. Our SR3D binaural microphones are perfect for recording binaural audio in all locations. Coming in multiple different design forms, they are compact, easily transportable, have different input options and most importantly are perfectly designed for capturing binaural audio. Remember to listen out for sounds above you, below you, and behind you approaching you for the very best binaural experience, let the sound come into the microphones naturally, rather than pointing the mics at it, and following the sound as it moves.

Depending on the location you are filming, you may need a windscreen or wind jammer to block any excess or unwanted wind noises finding their way into your recording, our fluffies work very well for wind protection.

Choosing The Right Microphone For Binaural Recording
​The key to binaural audio is using a microphone that can capture sound in the same way that our ears do.

Our SR3D microphones make this a lot easier as they are designed and built for the purpose of binaural audio recording, so you won’t need to calculate, measure or constantly reposition your microphones to capture the perfect binaural sound.

When played back through headphones, or neck speakers, the binaural audio creates an audio experience that is similar to being in the same environment as the recording, with sounds appearing to come from different directions and distances, as if the listener were actually there.