The Eminence Alpha 12A PA Speaker
is the ideal replacement speaker for 12 inch 2 way speaker systems and stage monitors. With an imedence of 8 ohms and a 300W Music Program rating, the Alpha 12A is a pefect fit in most portable PA speakers and monitors.
Materials of Construction
How a Speaker Works
- Kapton coil former
- Ferrite magnet
- Pressed steel basket
- Polyamide-imide coated copper voice coil
- Paper cone/cloth cone edge
- Solid composition paper dust cap
The key working components of a loudspeaker are shown in the diagram below. When an electrical current passes through a wire coil (the voice coil) in a magnetic field, it produces a force which varies with the current applied. The cone, connected to the voice coil, moves in and out, creating waves of high and low air pressure.
The coil and magnet assembly are the 'motor structure' of the loudspeaker. The movement is controlled by the loudspeaker's suspension which comprises the cone surround and the 'spider'. The surround and spider allow the coil to move freely along the axis of the magnet's core (or pole
) without touching the sides of the magnetic gap.
Eminence technology and proprietary materials mean that age-old compromises
of durability against sensitivity, or power handling against precision of response, are more easily solved than you might imagine.
: In the quest for higher power density (more power and hence more sound from less space), Eminence has progressively introduced heatsink components to selected transducers e.g. cast frame neodymium products and Kilomax. The heatsinks pass through the pole of the transducer or are incorporated into the chassis of the loudspeaker to transfer heat away from the coil. The air currents caused by the cone movement cool the heatsink.