ORTF Stereo
A near-coincident pair with cardioids 17 cm apart at 110 degrees
Related
ORTF comes from French broadcasting: two cardioid microphones with capsules about 17 cm apart, each angled outward to a total of roughly 110 degrees. The spacing approximates the ears, and the angle mimics a listener turning toward the source.
It keeps both time and level differences, so it is wider than XY yet more stable than a widely spaced A/B pair, and it still folds to mono usefully. Mount the pair at equal height with matched models, centred on the source. In a reflective room even a near-coincident pair may take in too much space.
The usual mistake is calling any slightly separated pair ORTF. The 17 cm spacing and 110-degree angle define it; change one and you have a different setup.
Sources
- 近同点立体声制式，参 Huber & Runstein, Modern Recording Techniques 与 Bartlett, Practical Recording Techniques；本文为原创表述
Used for fact-checking only; all prose is original.