AKG C 400 BL User Instructions page 20

If you use more than one microphone, make sure to
place the microphones about 10 feet (3 m) apart.
Listen to the microphone at several different locations
and install the microphone where it sounds best.
2.1.4. Conference Table
Referring to fig. 7, place the microphone near the front
edge of the tabletop, as close as possible to the talker
(the optimum talking distance would be 1 foot/30 cm),
but taking care to leave enough space for documents.
The acoustics of the conference room permitting, you
may use one microphone for two delegates each. This
reduces the number of microphones needed, noise due
to pages being turned, the number of mixer inputs re-
quired, etc.
In rooms with difficult acoustics, however, we recom-
mend to use one microphone for each delegate.
Fig. 7
20