JBL LSR708I 8" Master Reference Monitor

JBL Professional LSR708i - 8" Master Reference Monitor with Image Control Waveguide for Post Production and Broadcast

The JBL Professional LSR708i is the flagship 8” install of the 7 Series , designed for post-production suites, broadcast installations and mobile units that demand precise stereo imaging, frequency extension and high output level from a compact enclosure. It integrates the Image Control waveguide (derived from the M2) together with the next generation 2409H compression driver and an 8” 728G woofer , achieving linear response and a seamless transition between channels. Its architecture is designed for centralized amplification and processing (Crown DCi/BSS), which simplifies cabling, reduces system noise and facilitates scaling to multi-channel or immersive audio configurations.

With a response (±3 dB) from 45 Hz to 23 kHz and a usable range of 35 Hz to 36 kHz, the 708i exceeds 108 dB SPL continuous and 114 dB peak at 1 m. The front-ported , reinforced birch plywood enclosure maintains rigidity and minimizes port turbulence, allowing it to be installed in a bookshelf or flush ( soffit ) without performance degradation. Phoenix terminals accept wire up to 12 AWG (~3.3 mm²) , and the system supports single-wire or bi-amp operation with official tuning .

Main features

• Series 7 platform for post/broadcast control rooms and OB trucks; designed for multichannel and immersive systems.
• Latest generation transducers : HF 2409H (low mass annular diaphragm) and LF 728G (8”).
• Image Control Waveguide : Detailed image, neutral off-axis response, and colorless crossover transition.
• Response (±3 dB): 45 Hz–23 kHz ; range: 35 Hz–36 kHz; SPL: >108 dB continuous / >114 dB peak (1 m).
• 1.7 kHz crossover with switchable passive network; bi-amplification possible via dedicated tunings .
• Front-ported , compact, and reinforced mounting enclosure; mounting points at the top, bottom, and rear (4-hole pattern).
• Professional integration : presets/tunings for Crown DCi and BSS Soundweb London ; HiQnet/Audio Architect environment.
• Connectivity : Phoenix terminals for cables up to 12 AWG (~3.3 mm²).
• Compact dimensions (438 × 248 × 292 mm) and weight of 11.5 kg per unit.

Product benefits

• Reference accuracy and room-to-room consistency thanks to Image Control guidance and certified tunings .
• Greater dynamic range useful for demanding mixes: high working levels with low distortion and power compression.
• Simplified installation : centralized amplification/DSP (BLU link) eliminates power at each point and reduces system noise.
• System flexibility : single-wire or bi-amplified operation, versatile mounting (wall, ceiling, soffit/shelf).
• Scalable to immersive : natural combination with other 7 Series and with the JBL M2 master monitor.

Use cases

• Post-production control rooms (film/TV), broadcast and mobile units with 5.1/7.1/immersive systems.
• Studios requiring high SPL and bandwidth extension with reduced footprint .
• Facilities with centralized amplification and processing (Crown DCi / BSS London / Intonato 24).

Integration and adjustment

• Official tunings for Crown DCi (single-wire and bi-wire/bi-amp modes) and for BSS Soundweb London , ready to load from Audio Architect or London Architect.
• Typical amplification requirement : 300W per channel and HARMAN (Crown DCi “N”) or BSS London processing with suitable external amplifier.
• Wiring : Phoenix terminals; recommended 12 AWG (~3.3 mm²). This gauge allows runs of up to ~30 m per channel.

Frequently Asked Questions

• Is the 708i active? No. It's a passive "install" monitor and requires external amplification and a HARMAN DSP (Crown DCi or BSS).
• Can it be bi-amped? Yes. The crossover network can be bypassed and operated in bi-amp mode with specific HF/LF presets.
• How is it mounted? It has mounting points on the top, bottom, and back (4-hole pattern) for wall/ceiling mounting, as well as for use on shelves or in recessed ( soffit ) installations.
• What differentiates it from the 708P? The 708i is passive and designed for centralized amplification/DSP; the 708P is self-powered.

Description for projects

2-way passive reference monitor with Image Control waveguide. Transducers: HF 2409H (compression, annular diaphragm) and LF 728G (8 ” ≈ 203 mm). Crossover : 1.7 kHz. Response (±3 dB): 45 Hz–23 kHz; range : 35 Hz–36 kHz. Max. SPL (80 Hz–20 kHz): >108 dB continuous / >114 dB peak at 1 m. Connection : Phoenix terminals (accepts 12 AWG ~3.3 mm²). Enclosure : Reinforced birch plywood, front ported; top/bottom/rear mounting points (4-hole pattern). Dimensions : 438 × 248 × 292 mm. Weight : 11.5 kg. Operation : Single-wire or bi-amp with official Crown DCi/BSS tunings .