- 4″ 30W coaxial driver (4A30) has 135 degree dispersion for large coverage areas.
- Driver’s capacity to deliver wide angle sound distribution at 2kHz, with uniform response and clear audibility, ensures complete coverage with minimum units.
- Transformer (TLM-870) is 70V with taps at 1, 2, 4, 8W
- Grille (WB-4) is one-piece punched steel construction. Screw-mount. 7.25 inch diameter. White.
- Country of origin: Assembled in U.S.A. with U.S. steel grille and global components
The speaker assembly shall be Lowell Model WB4-4A30-T870S, which shall include a 4” driver, 70V transformer and grille. The driver shall be of the coaxial type with high and low frequency transducers. Low frequency section shall have a 4” dia. polypropylene cone; high frequency section shall have a tweeter with a 1″ dia. balanced-drive dome. Built-in crossover network shall be employed to accomplish proper frequency division between the two drivers. Crossover frequency shall be at 5kHz with first order high-pass filter. It shall be capable of producing a uniform audible frequency response over the range of 70Hz-20kHz (+6dB) and 50Hz-20kHz (+8.8dB) with dispersion angle of 135 degrees @2000Hz (-6dB). Average sensitivity shall measure 88.0dB (SPL at 1W/1M). Rated power handling shall be 30W (EIA 426B). The 1″ dia. low frequency voice coil shall operate in a magnetic field derived from a ferrite (ceramic) magnet with nominal weight of 10oz.; the 0.53″ dia. high frequency voice coil shall operate in a magnetic field derived from a Neodymium magnet with 0.06oz. nominal weight. Voice coil impedance shall be 8 ohms. Frame shall be structurally reinforced stamped 20-ga. steel with 5″ overall dia., 4 round and 4 obround holes equally spaced on 4.67” dia. mounting bolt circle. External metal parts shall be finished in black enamel paint or zinc plating to resist rust/corrosion. Transformer shall have primary taps at 8, 4, 2, 1W and frequency response of 50Hz-15kHz (+1dB). It shall be factory-mounted to top of driver, which shall be mounted to a punched steel screw-mount grille with 7.25” dia. and white powder epoxy finish.
