JBL SR4738A
The JBL SR4738A is a professional sound reinforcement loudspeaker system — a two-way, horn-loaded cabinet built for live sound work. The documentation on this model is thin, but what survives paints a clear picture of a workhorse speaker aimed at the touring and installed-sound market.
The design is straightforward: a 400mm (15") low-frequency driver paired with a 60mm (2.4") high-frequency compression driver, crossed over at 1.3kHz. The horn provides 100°H x 100°V dispersion, which is wide and even — typical for a main PA cabinet meant to cover a broad area from a single cluster. It's rated at 450 watts maximum power input, with a sensitivity of 100dB SPL (1W, 1m) and an 8-ohm impedance. Frequency response is listed at 45Hz–18kHz.
The enclosure is trapezoid-shaped, built from heavy-duty plywood, with recessed handles and a 36mm pole mount socket. It's bi-amp switchable, meaning you can run it passively with the internal crossover or actively bi-amp it for more control. Input is via dual Neutrik NL4MP SpeakON connectors, wired Pin 1+ / 1- for full range. The "multi-pole port design" is mentioned in the spec sheet, though details on exactly what that entails aren't documented.
One period mention places the SR4738A in a professional touring context: EQ Magazine (January 1999, p.102) noted it in a piece about a working sound system, alongside rack gear and Neutrik NL4 connectors — a small glimpse of the speaker in its intended environment.
A secondhand listing in Australia shows an RRP of AUD $1,999, though the date of that listing isn't specified. No production years, dimensions, weight, or owner reviews have surfaced in the available record.
Known Specs
- Type: Two-way, horn-loaded professional sound reinforcement loudspeaker
- Drivers: 400mm (15") LF, 60mm (2.4") HF compression driver
- Crossover: 1.3kHz
- Frequency response: 45Hz–18kHz
- Sensitivity: 100dB (1W, 1m)
- Power: 450W maximum input
- Impedance: 8 ohms
- Dispersion: 100°H x 100°V
- Inputs: Dual Neutrik NL4MP SpeakON (Pin 1+ / 1- = full range)
- Features: Bi-amp switchable, trapezoid plywood enclosure, recessed handles, 36mm pole mount
- Original price: AUD $1,999 (RRP, date unspecified)
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