ORTF Stereo – Definition & Detailed Explanation – Recording Techniques Glossary

What is ORTF Stereo?

ORTF Stereo is a specific microphone technique used in audio recording to create a realistic stereo image. It was developed by the French national broadcasting organization, Office de Radiodiffusion Télévision Française (ORTF), hence the name. This technique involves using a pair of cardioid microphones spaced apart at a specific angle and distance to capture sound in a way that closely resembles how the human ears perceive it.

How does ORTF Stereo work?

ORTF Stereo works by positioning two cardioid microphones at an angle of 110 degrees from each other and spaced 17 centimeters apart. This setup mimics the spacing and angle of the human ears, allowing for a more natural and realistic stereo image. The cardioid microphones are chosen for their directional pickup pattern, which helps to reduce unwanted ambient noise and focus on the sound source.

What are the advantages of using ORTF Stereo?

There are several advantages to using ORTF Stereo for recording. One of the main benefits is the realistic stereo image it produces, which can create a more immersive listening experience for the audience. The spacing and angle of the microphones help to capture the spatial characteristics of the sound, making it feel more natural and three-dimensional. Additionally, the use of cardioid microphones helps to isolate the sound source and reduce unwanted background noise, resulting in a cleaner recording.

When should ORTF Stereo be used in recording?

ORTF Stereo is a versatile technique that can be used in a variety of recording situations. It is particularly well-suited for capturing live performances, such as concerts or theater productions, where a realistic stereo image is desired. It can also be used for recording acoustic instruments, vocals, and sound effects, as it can accurately capture the spatial characteristics of the sound. ORTF Stereo is not limited to any specific genre of music or type of recording, making it a popular choice among audio engineers.

What equipment is needed for ORTF Stereo recording?

To set up an ORTF Stereo recording, you will need a pair of cardioid microphones, a microphone stand or mounting bar, and a recording device. The cardioid microphones should have a flat frequency response and low self-noise to ensure accurate and clean recordings. It is also important to use a shock mount or isolation device to reduce handling noise and vibrations. Additionally, a pop filter or windscreen may be necessary to prevent plosives and wind noise from affecting the recording.

How to set up ORTF Stereo recording?

To set up an ORTF Stereo recording, follow these steps:
1. Position the microphone stand or mounting bar so that the two cardioid microphones are spaced 17 centimeters apart.
2. Angle the microphones at 110 degrees from each other, with the capsules pointing outward.
3. Place the microphones at a height that is level with the sound source, such as a musical instrument or vocalist.
4. Connect the microphones to the recording device using XLR cables, making sure to check the polarity and phase alignment.
5. Adjust the input levels on the recording device to ensure a clean signal without clipping.
6. Monitor the recording through headphones to check for any issues or adjustments that may be needed.
7. Start recording and capture the sound with the ORTF Stereo technique to create a realistic stereo image.