A quick trick. It’s not always easy to get your stereo mics spaced well. Here’s an easy way to get your measurements. Go to ORTF Stereo Technique on Wikipedia. Click on the diagram on that page. Print it out. You can use it to easily align your microphones.
ORTF Microphone Spacing
Wikipedia also has pages for XY spacing and other configurations. Oh, and by the way, ORTF miking is great for acoustic guitar. Give it a try sometime.
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The angle is correct, but now the spacing of the front of the mics is greater than 17 cm (6.9″or so).
Gabe…How can you tell?