18 Sound 10NTLS2000 – LF Drivers

18 Sound 10NTLS2000 – Long-Throw 10-Inch Neodymium Subwoofer with Tetracoil Motor and Maximum Excursion at 1.9 kg

The 18 Sound 10NTLS2000 is the long-throw subwoofer variant of 18 Sound’s Tetracoil 51 mm voice coil platform — sharing the same motor architecture, the same 1.9 kg weight, and the same body dimensions as the 10NTLW2000 woofer, but with a 19 mm winding depth that produces 7.4 mm of linear excursion versus the woofer’s 4.4 mm. Where the 10NTLW2000 optimises for mid-bass sensitivity at 98.5 dB, the 18 Sound 10NTLS2000 optimises for bass displacement — 68% more Xmax at the cost of 1.5 dB sensitivity and 2000 Hz of upper bandwidth.

The 7.4 mm Xmax at 1.9 kg is the specification that defines the 18 Sound 10NTLS2000’s value. No other 18 Sound 10-inch driver delivers this much displacement at this weight. The 10NW750 achieves 7.5 mm at 3.8 kg. The 10NTLW2500 achieves 7.6 mm at 3.1 kg. The 10NTLW3500 achieves 7.9 mm at 4.2 kg. The 18 Sound 10NTLS2000 achieves 7.4 mm at 1.9 kg — within 0.5 mm of the range-leading 10NTLW3500’s displacement at less than half the weight.

The engineering mechanism is identical to the 8NTLS2000 versus the 8NTLW2000: a deeper voice coil winding in the same dual gap. The 19 mm winding depth (versus 13 mm on the 10NTLW2000) provides more coil overhang above and below the 8.5 mm gap, extending linear excursion at the cost of moving mass, sensitivity, and upper bandwidth. The 47 g Mms is 24% heavier than the 10NTLW2000’s 38 g — the additional conductor mass from the deeper winding.

The 50 Hz Fs is the lowest of any Tetracoil 10-inch driver — 7 Hz below the 10NTLW2000’s 57 Hz. The 50 Hz – 3000 Hz bandwidth targets bass and mid-bass reproduction from a sub-optimised alignment.

At 1.9 kg, 260 mm overall diameter, 233 mm baffle cutout, 141 mm depth — physically identical to the 10NTLW2000. Available in 8 Ω.

Design and Construction of the 18 Sound 10NTLS2000

The 18 Sound 10NTLS2000 uses a 51 mm (2-inch) aluminium dual voice coil operating in the same Tetracoil (TTC) neodymium dual-gap motor as the 10NTLW2000. Same magnet assembly, same dual gap structure, same 8.5 mm gap depth. The voice coil winding is the single engineering change.

The 19 mm winding depth in the 8.5 mm dual gap has 10.5 mm of overhang (5.25 mm per side) versus the 10NTLW2000’s 13 mm winding with 4.5 mm of overhang. The additional 6 mm of winding depth translates to 3 mm of additional linear excursion — 7.4 mm versus 4.4 mm.

The 16.7 Tm force factor is slightly lower than the 10NTLW2000’s 17.9 Tm — the coil sections furthest from the gap centre experience slightly weaker flux, averaging the force factor downward. The 16.7 Tm driving 47 g still provides strong motor authority — the Qts of 0.26 confirms firm electromagnetic control over the heavier moving mass.

The Tetracoil dual-gap architecture provides the same thermal and Bl symmetry advantages. The doubled coil surface dissipates heat twice as efficiently as a single-gap design, sustaining the 350 W AES / 700 W program power rating. The symmetrical Bl keeps intermodulation distortion low at the high displacement levels that bass reproduction demands.

The 0.74 mH Le is slightly higher than the 10NTLW2000’s 0.63 mH — the deeper winding places more conductor in the gap, increasing inductance. For the 3000 Hz upper bandwidth, the inductance is well-managed.

At 1.9 kg, every physical dimension matches the 10NTLW2000 exactly. The two drivers are completely interchangeable in the same cabinet.

Performance and Applications for the 18 Sound 10NTLS2000

The 18 Sound 10NTLS2000 delivers 97 dB sensitivity across a 50 Hz – 3000 Hz bandwidth. The 50 Hz lower frequency limit is 10 Hz deeper than the 10NTLW2000’s 60 Hz — the heavier moving mass and deeper winding push the resonance frequency down to 50 Hz, extending the driver’s bass range.

The 7.4 mm Xmax combined with 346 cm² of radiating area produces approximately 256 cm³ of volume displacement — 68% more than the 10NTLW2000’s 152 cm³. For compact subwoofer cabinets and bass sections in portable PA systems, this displacement capability produces genuine low-frequency output from the lightest 10-inch in the range.

The 0.26 Qts and 50 Hz Fs indicate the 18 Sound 10NTLS2000 produces tight, well-controlled bass in vented enclosures. The motor-dominant alignment keeps the bass fast and defined even at high displacement levels.

The 350 W AES / 700 W program power handling matches the 10NTLW2000 — same thermal capacity from the same Tetracoil dual-gap motor.

The physical interchangeability with the 10NTLW2000 gives system designers a matched woofer/sub pair from the same 1.9 kg platform. One cabinet design serves both — the 10NTLW2000 for mid-bass sensitivity, the 18 Sound 10NTLS2000 for bass displacement.

Within the complete 10-inch range, the 18 Sound 10NTLS2000 occupies a unique position. It’s the only dedicated sub-optimised 10-inch driver in the catalogue. The 10NTLW3500 produces more total displacement (273 cm³ at 7.9 mm Xmax) but weighs 4.2 kg. The 10NW750 produces 255 cm³ at 7.5 mm Xmax but weighs 3.8 kg. The 18 Sound 10NTLS2000 produces 256 cm³ at 1.9 kg — comparable displacement to the 10NW750 at half the weight.

Conclusion – 18 Sound 10NTLS2000 Subwoofer Driver

The 18 Sound 10NTLS2000 is the displacement variant of 18 Sound’s Tetracoil 51 mm platform — the same motor, the same body, the same 1.9 kg weight as the 10NTLW2000. The 19 mm winding depth produces 7.4 mm of linear excursion — 68% more than the woofer’s 4.4 mm — trading sensitivity and bandwidth for the bass displacement that sub-bass applications demand.

The 1.9 kg weight with 7.4 mm Xmax is unmatched. No other 18 Sound 10-inch delivers this much displacement at this weight. The 10NTLW3500’s 7.9 mm Xmax exceeds the 18 Sound 10NTLS2000 by only 0.5 mm but weighs 2.3 kg more. For compact subs, line array bass elements, distributed bass systems, and any application where a 10-inch sub needs maximum displacement from minimum weight, the 18 Sound 10NTLS2000 is the sub half of the lightest 10-inch platform in professional audio.