JBL GSB8 TN Underground Landscaping Subwoofer

JBL Professional GSB8-TN - 8" buried landscape subwoofer with 70/100 V and IP66 transformer

The JBL Professional GSB8-TN is an in-ground landscape subwoofer designed to extend the low end of commercial outdoor systems with true sub-bass performance down to 35Hz . Designed to integrate with JBL GSF series satellites, it combines an 8" polypropylene driver and an internal multi-slope low-pass filter that ensures a clean transition with the satellites. Its robust yet discreet construction leaves only the port cover exposed, offering an integrated aesthetic in gardens, terraces and lawns in hotels, retail and corporate spaces.

For maximum flexibility, the GSB8-TN operates on both low-impedance (6 Ω) and 70/100 V distributed lines using a subwoofer-band transformer with selectable power taps. The 6 mm LDPE polyethylene enclosure and painted stainless steel grille provide the necessary outdoor protection, with the assembly rated IP66 overall. The design includes handles for easy installation and a base plate with tabs for secure anchoring. This Tan (sand) finish blends into a wide variety of landscapes.

Main features

• 8" (209 mm) transducer with 38 mm voice coil on Kapton former and TPV suspension for high reliability.
• True extension down to 35 Hz with internal multi-slope low-pass filter for better integration with satellites.
• 6 Ω / 70 V / 100 V operation thanks to high-quality subwoofer band transformer.
• Weatherproof construction : LDPE enclosure (minimum 6 mm wall) and stainless steel grille ; IP66 rating (bottom of cabinet up to IP68).
• Omnidirectional coverage : 360° horizontal × 160° vertical (main listening 10°–50° above ground).
• Simplified installation with included handles, base plate with anchoring tabs and dielectric gel nuts.
• Available finishes : Tan (TN) and Hunter Green (GN) .

Acoustic performance

• Frequency range (-10 dB): 35 Hz – 130 Hz.
• Response (±3 dB): 43 Hz – 120 Hz.
• Average sensitivity (43–110 Hz): 84 dB.
• Max SPL at 1 m: 114 dB peak / 108 dB continuous (2 h).
• Permissible power: 250 W (continuous pink noise, 2 h); 500 W program (2 h); 1000 W peak (2 h).

Product benefits

• Deep and controlled bass without impacting the aesthetics of the space.
• Scalability for distributed systems: selection of 70/100 V taps or 6 Ω mode.
• True outdoor durability : IP66, anti-corrosion materials, and professional-grade environmental testing.
• Easy integration with JBL GSF landscape speakers for coherent broadband systems.

Recommended installation

• Indicative construction hole for GSB8: 465 mm diameter × 630 mm deep (leave the base of the port cover ≥ 100 mm above the finished ground).
• Input wiring : 7-conductor captive bundle (1 m, 14 AWG ≈ 1.6 mm² ), connection with gel-coated nuts in the installer's watertight box.
• 70/100V sockets (wire color selection): 70V 30/60/120W ; 100V 60/120W . Direct mode: 6Ω .
• Recommended high-pass filter (24 dB/Oct): 35 Hz into 6 Ω and 30 W; 45 Hz into 60 W; 55 Hz into 120 W.

Use cases

• Hotels, resorts and theme parks.
• Shopping centers, restaurants and outdoor leisure areas.
• Corporate campuses, municipal gardens, and landscaping of sports venues.

Frequently Asked Questions

• Can I use it with existing satellites? Yes, it works with JBL GSF landscape speakers and can be integrated with other compatible satellites by adjusting the level and EQ.
• Do you need a junction box? Yes, the connection is made in a watertight box provided by the installer, using the included gel-coated connectors.
• What is the IP rating? The installed assembly is IP66 ; the bottom of the cabinet reaches IP68 .

Description for projects

8" (209 mm) in-ground landscape subwoofer. Range (-10 dB) 35–130 Hz ; response (±3 dB) 43–120 Hz ; sensitivity 84 dB (43–110 Hz); max. SPL 114 dB peak / 108 dB continuous at 1 m. Nominal impedance 6 Ω (direct mode). Subwoofer transformer: 70 V 30/60/120 W , 100 V 60/120 W taps; recommended HPF 35/45/55 Hz depending on tap (24 dB/Oct). Transducer: polypropylene, 38 mm voice coil on Kapton former, TPV suspension. LDPE enclosure (6 mm wall) with painted stainless steel grille ; IP66 protection (bottom up to IP68). Coverage 360° H × 160° V . Dimensions 768 × Ø 311 mm . Net weight 9.3 kg . Tan (TN) color. Accessories: base plate with anchoring tabs and 7 gel-coated nuts.