JBL M2 Owner's Manual page 10

Horizontal placement
The M2 speakers can be used in a horizontal orientation.
When used horizontally, each M2 should be
elevated so the JBL logo is at ear height.
Toe-in may be required to provide optimum
coverage. The closer the listeners are to the
speakers, the more toe-in will be required.
(See example below.)
8
Orienting the speakers with waveguides
towards the inside and woofers outside
may be preferable in installations where the
listeners are unusually close to the speakers.
The speaker's rubber feet may be removed
when mounting the M2 in a soffit.
Horizontal Placement