18 Sound 8NTLW2000 – Ultra-Light 8-Inch Neodymium Woofer with Tetracoil Dual Gap Motor and 350 Watt Power Handling
The 18 Sound 8NTLW2000 is the lightest and most motor-dominant 8-inch woofer in 18 Sound’s range. At 1.5 kg — lighter than the 8NMB420’s 1.7 kg and 900 g lighter than the 8NW650’s 2.4 kg — with a 51 mm Tetracoil dual voice coil operating in the same 8.5 mm dual magnetic gap found across 18 Sound’s entire NTLW2000 family, 17.5 Tm force factor, 97.5 dB sensitivity, 350 W AES / 700 W program power handling, and a Qts of 0.21 that is the most motor-dominant alignment of any 18 Sound 8-inch woofer, the 18 Sound 8NTLW2000 delivers dual-gap technology and power handling that the 8-inch format has never seen at this weight.
The 1.5 kg weight is the headline. A complete 8-inch woofer with a Tetracoil dual-gap motor, 17.5 Tm force factor, and 350 W AES power handling at one and a half kilograms. For line arrays where per-element weight determines total array mass, rigging requirements, and transport logistics, the 18 Sound 8NTLW2000 saves 900 g per driver versus the 8NW650 while handling 50 W more power and producing 1.5 dB more sensitivity. In a 16-element array using dual 8-inch drivers per element, the weight saving is 28.8 kg — enough to change rigging motor sizing and structural certification.
The 17.5 Tm force factor is the highest of any 18 Sound 8-inch woofer (excluding the sealed-back 8NM610 midrange). It exceeds the 8NW650’s 15.2 Tm by 15% and the 8NMB420’s 10 Tm by 75%. The Tetracoil dual-gap motor generates this force factor through the same mechanism used on the 6.5 and 10-inch NTLW2000 variants — the 51 mm coil operates in two magnetic gaps, doubling the effective conductor length in the field and producing more force per ampere with doubled thermal dissipation.
18 Sound describes the 18 Sound 8NTLW2000 as the smallest Tetracoil motor structure in the family at 8 inches, using the same concept to maximise thermal dissipation and Bl symmetry across a wide frequency band — making it the perfect component both as a woofer and a mid-bass for highest-quality line arrays and multi-way systems. Available in 8 and 16 Ω.
Design and Construction of the 18 Sound 8NTLW2000
The 18 Sound 8NTLW2000 uses a 51 mm (2-inch) CCAW aluminium dual voice coil operating in a Tetracoil (TTC) neodymium dual-gap motor assembly. The motor is the same architecture found on the 6NTLW2000 and 10NTLW2000 — a 51 mm coil in an 8.5 mm dual magnetic gap with 13 mm winding depth. The same coil, the same gap, the same fundamental motor across all three format sizes.
The dual gap doubles the coil surface exposed to the magnetic field, producing two simultaneous benefits. First, thermal dissipation that is twice as efficient as single-gap drivers — the 51 mm coil at 1.5 kg handles 350 W AES, matching the 10NTLW2000’s power rating from a driver that weighs 400 g less. Second, Bl symmetry that maintains consistent force output across the excursion range, keeping intermodulation distortion at what 18 Sound describes as the lowest in the professional market.
The 17.5 Tm force factor driving 28 g of moving mass produces 97.5 dB sensitivity, 2.2% reference efficiency, and the most extreme motor-dominant alignment of any 18 Sound 8-inch woofer. The Qts of 0.21 is the lowest. The EBP of 338 Hz is the highest. The Bl/Mms ratio of 0.625 Tm/g exceeds the 8NW650’s 0.585 Tm/g. Every motor metric confirms the Tetracoil’s absolute authority over the 28 g cone assembly.
The Tetracoil motor linearises inductance through the symmetrical dual-gap configuration. The 0.63 mH Le stays consistent across the excursion range — the symmetrical magnetic circuit prevents the inductance modulation that single-gap motors produce as the coil moves in and out. This inductance stability is the mechanism behind the extended mid-band clarity that 18 Sound highlights as a defining characteristic of all Tetracoil drivers.
The curvilinear paper cone features a water and UV repellent treatment — the first UV-resistant cone treatment in any 18 Sound driver we’ve covered. The UV protection prevents degradation from sustained sun exposure, which is a specific durability requirement for outdoor touring rigs and permanent outdoor installations where the drivers face direct sunlight during daytime events.
The double roll surround provides controlled compliance through the 4.4 mm Xmax with 5.0 mm Xvar. The ultra-linear suspension works with the Tetracoil motor to allow both high excursion and extreme mid-band precision — the 18 Sound 8NTLW2000 operates both as a woofer (from 70 Hz) and a mid-bass (through 4500 Hz) without compromising either role.
At 1.5 kg, 210 mm overall diameter, 186 mm baffle cutout, 121 mm depth, and 9 mm flange, the 18 Sound 8NTLW2000 is the lightest 8-inch driver in 18 Sound’s range. The 186 mm cutout matches the standard 18 Sound 8-inch mounting interface.
Performance and Applications for the 18 Sound 8NTLW2000
The 18 Sound 8NTLW2000 delivers 97.5 dB sensitivity across a 70 Hz – 4500 Hz bandwidth. The 97.5 dB is 1.5 dB above the 8NW650’s 96 dB and 2.5 dB above the 8NMB420’s 95 dB — the highest sensitivity of any 18 Sound 8-inch woofer. At 350 W AES, the maximum sustained output exceeds every other 8-inch woofer in the range.
The 350 W AES / 700 W continuous program power handling is the highest of any 18 Sound 8-inch woofer — 50 W more than the 8NW650’s 300 W and 70 W more than the 8NMB420’s 280 W. The Tetracoil dual-gap motor’s doubled thermal dissipation sustains this rating from the compact 51 mm coil — achieving more power handling than the 8NW650’s larger 65 mm single-gap coil.
The 0.21 Qts and 338 Hz EBP are the most extreme motor-dominant alignment of any 18 Sound 8-inch woofer. These parameters confirm the 18 Sound 8NTLW2000 is designed for vented enclosures where the Tetracoil motor’s extreme damping produces the tightest, fastest, most controlled bass and mid-bass output possible from the 8-inch format.
18 Sound recommends a 15-litre (0.53 ft³) vented enclosure tuned to 100 Hz. The high 100 Hz tuning frequency targets punchy, fast mid-bass in the 80–300 Hz range — the sweet spot for compact two-way PA tops and line array elements. The 70 Hz lower frequency limit confirms the 18 Sound 8NTLW2000 reaches into the upper bass for systems operating without a dedicated sub.
The 4500 Hz bandwidth is narrower than the 8NW650’s 6300 Hz — 1800 Hz less upper-frequency extension. For systems crossing over at 2000 Hz, both drivers provide adequate overlap with the compression driver. For systems crossing over above 2000 Hz, the 8NW650’s wider bandwidth provides more headroom. The 18 Sound 8NTLW2000’s bandwidth trade-off is the consequence of the 28 g moving mass — heavier than the 8NW650’s 26 g — but the extra mass carries the higher Bl and dual-gap motor that produce more power handling and more sensitivity.
The Tetracoil family comparison across format sizes places the 18 Sound 8NTLW2000 precisely in the middle. The 6NTLW2000 (6.5-inch) delivers 93 dB at 320 W from 1.2 kg with 8 kHz bandwidth. The 18 Sound 8NTLW2000 (8-inch) delivers 97.5 dB at 350 W from 1.5 kg with 4500 Hz bandwidth. The 10NTLW2000 (10-inch) delivers 98.5 dB at 350 W from 1.9 kg with 5000 Hz bandwidth. Same 51 mm coil, same 8.5 mm dual gap, same 13 mm winding depth — scaling in sensitivity and cone area with format size.
The 18 Sound 8NTLW2000 offers the best balance point in the Tetracoil family for many line array applications. It’s only 300 g heavier than the 6.5-inch (1.5 vs 1.2 kg) but produces 4.5 dB more sensitivity. It’s 400 g lighter than the 10-inch (1.5 vs 1.9 kg) with only 1 dB less sensitivity. For line array designs where the driver format must balance output per element against weight per element, the 8-inch Tetracoil sits in the sweet spot.
Conclusion – 18 Sound 8NTLW2000 Woofer
The 18 Sound 8NTLW2000 is the lightest, most powerful, and most motor-dominant 8-inch woofer in 18 Sound’s range. The Tetracoil dual-gap motor delivers 17.5 Tm of force factor, 350 W AES power handling, and 97.5 dB sensitivity from a package that weighs 1.5 kg. No other 18 Sound 8-inch woofer matches any of these figures — and the 18 Sound 8NTLW2000 leads on all of them simultaneously.
The same 51 mm coil and 8.5 mm dual gap used on the 6.5 and 10-inch NTLW2000 drivers produce the same dual-gap benefits at the 8-inch scale: doubled thermal dissipation, symmetrical Bl, linearised inductance, and the lowest intermodulation distortion in the format. The water and UV repellent cone treatment adds outdoor durability that no other 18 Sound 8-inch driver matches.
For ultra-light line arrays, compact two-way systems, and any application where an 8-inch woofer needs to deliver the most power, the highest sensitivity, and the strongest motor from the lightest possible package, the 18 Sound 8NTLW2000 is the 8-inch that brings Tetracoil technology to the format where weight matters most. One and a half kilograms, 350 watts, 17.5 Tesla-metres, 97.5 dB — the Tetracoil 8-inch.
VIEW MORE 18 Sound PRODUCTS HERE.
About 18 Sound
18 Sound products are proudly made in Reggio Emilia, Italy, combining advanced technology with Italian craftsmanship. Known for their high-performance professional audio components, 18 Sound is a trusted name in the global audio industry. Their state-of-the-art manufacturing and strict quality control ensure exceptional reliability and sound clarity. 18 Sound products are designed to meet the demands of speaker builders and audio professionals, 18 Sound offers premium products with outstanding value and performance worldwide.
