Overview
Speaker model WB4-4A30-T870-S is engineered as a step-up in sound quality and performance over standard commercial coaxial drivers. The four-inch 30W speaker with 70V shallow-mount transformer provides very high quality paging and background music reproduction. The assembly is ideally suited for audio distribution in hotel lobbies, retail stores, transportation terminals, and similar venues.
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.
Features
- 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.
