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A lot of studio monitoring situations will have stereo speakers with half-span angles anywhere from 20-35º (or higher).
A far-field listening room may have speakers from 15-30º.
A computer with symmetrical speakers to each side of the keyboard would be somewhere from 12-18º, a tablet held horizontally would be a similar range, and a soundbar several feet away could range from under 10-14º.
Please note these are ballpark numbers, just to give you an idea of where to start looking for your own devices.
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