AKG C 1000 S - PPC 1000 & PB 1000 User Instructions page 15

Fig. 4a Fig. 4b
Important
To ensure high gain-before-feedback, never cover the rear sound entry
ports with your hand (see fig. 5) because this would destroy the car-
dioid/hypercardioid pickup pattern and cause the microphone to pick
up sound from all around including your monitor speakers, the result
being drastically reduced gain-before-feedback.
Fig. 5
Flute:
It is not easy to pick up the flute perfectly because the sound energy is
projected both by the embouchure and the first open fingerhole. In
other words, the flute radiates sound as a dipole projecting no
frequency range, not even the lowest, all around.
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