The coaxial 4 (EIA 5) driver shall be Lowell Model 4A30. It shall have a high frequency transducer (tweeter with 1 dia. balanced drive dome) and low frequency transducer (4 dia. polypropylene cone). A built-in electrical crossover network shall be employed for proper frequency divisions. Crossover frequency shall be at 5kHz with a first order high-pass filter. The 4A30 shall be capable of producing a uniform audible frequency response over the range of 81Hz-20kHz (+6dB); 50Hz-20kHz (+8.1dB) with dispersion angle of 135 degrees @2000Hz -6dB. Average sensitivity shall measure 87.8dB (SPL at 1W/1M). Power rating shall be 30 watts (EIA 426B). The low frequency voice

coil shall have 1 diameter and operate in a magnetic field derived from a ferrite (ceramic) magnet with nominal weight of 10 oz. The high frequency voice coil shall have a 0.53 dia. and operate in a magnetic field derived from a Neodymium magnet with nominal weight of 0.06 oz. Voice coil impedance shall be 8 ohms. The assembly shall have a round, structurally reinforced, stamped 20-gauge steel frame to maintain precise mechanical alignment. Overall diameter shall be 5 with four round and four obround holes equally spaced on a 4.66 dia. mounting bolt circle. Mounting depth shall not exceed 2.25. External metal parts shall be finished in black enamel paint or zinc plating.

Specifications

• Description: 4 in. 30W coaxial driver with 10 oz. magnet, 1 copper voice coil, and polypropylene cone with half-roll rubber surround for long cone travel and good edge damping
• Basket: 20-ga. stamped steel, black enamel paint
• Mounting Depth: 2.25 in.
• Mounting Bolt Circle: 4.66 in.
• Dispersion Angle: 135 degrees conical
• Frequency Response: 81Hz-20kHz (6dB); 50Hz-20kHz (8.1dB)
• Average Sensitivity: 87.8dB