18SOUND 10NTLW2500
18SOUND (Eighteen Sound) 10NTLW2500 — 10" / 10 inch · Woofer/Midrange (WM) · Bass · Neodymium · Dual-Gap
2x2.5" voice coil · 8 Ω
Part no.: 42A-CHS-TT-18S-0070
Documents
18SOUND 10NTLW2500 — 10" · Woofer
500 W AES · 96.5 dB Sensitivity · Frequency range 55 Hz – 4500 Hz
Technical data
- Diameter: 10 "
- Voice coil: 2.5 "
- Power handling: 500 W AES
- Sensitivity: 96.5 dB
- Impedance: 8 Ω
- Magnet: Neo
- Weight: 3.1 kg
- Mounting depth: 157 mm
- Frequency range: 55 – 4500 Hz
Datasheet (PDF) · Manufacturer page
Series: NTLW · Part no.: 42A-CHS-TT-18S-0070
18Sound 10NTLW2500: 10" neodymium woofer with dual-gap motor, 500 W AES and 3.1 kg
The special part of the 18Sound 10NTLW2500 is its motor: the neodymium drive works with two air gaps and a 2x2.5" double voice coil. This dual-gap construction from the NTLW series increases force in the magnetic field without making the coil heavier and at the same time improves heat transfer, because two coil sections face two pole plates. The result is BL of 17.4 Tm, 500 W AES power handling and a 10" driver that weighs only 3.1 kg.
With 96.5 dB sensitivity, Fs 65 Hz and Qts 0.33 the 10NTLW2500 is a woofer/midrange for compact tops and line array elements where a 10" driver has to cover bass and midrange up to the handover to the compression driver. Xmax of 7.6 mm is generous for this class, and the moving mass of 49 g keeps the usable range open to 4,500 Hz. Le of 0.45 mH is a low figure that translates into a flat impedance curve through the midrange.
Use and enclosure
For a 2-way top in a vented box the guide value is 13 l with fb 74 Hz and f3 80 Hz. That is a compact cabinet which, with 7.6 mm of excursion, delivers solid level in the kick-bass region; for real low end you add a subwoofer with a crossover set well above 55 Hz. A sealed box of 5.8 l with fc 139 Hz is the guide value for midrange chambers in 3-way systems. The EBP of 191 shows both routes are plausible, free-field deep bass is not.
The range ends at 4,500 Hz, which allows a comfortable handover to 1" and 1.4" compression drivers on horns from the 18Sound range. The driver comes in 4, 8 and 16 Ω variants; the 8 Ω version has Re 5 Ω. Similar parameters are found in the FaitalPRO 10PR330 with Fs 60 Hz, Qts 0.33 and Vas 32.5 l, and in the B&C 10NDL88 with Fs 67 Hz, Qts 0.32 and Vas 15.6 l; both are in the driver database at 42.audio for comparison.
What to look out for
- Dual-gap neodymium with 2x2.5" coil: BL 17.4 Tm at only 3.1 kg.
- Mounting depth 157 mm: deeper than usual 10" drivers, check cabinet depth.
- Xmax 7.6 mm: a high-pass above 55 Hz makes sensible use of the excursion.
- Qms 11.2: low mechanical losses, damping comes from the motor.
- Variants 4/8/16 Ω: choose the impedance to match the amplifier.
Frequently asked questions
What does the dual-gap motor of the 10NTLW2500 deliver in practice?
Two air gaps, each with its own coil section, raise BL to 17.4 Tm and spread the heat over two contact areas. That reduces compression at the 500 W AES rating and keeps the driver light at 3.1 kg.
Which enclosure suits the 10NTLW2500 in a 2-way top?
A vented box of about 13 l tuned to 74 Hz as a guide value, giving an f3 around 80 Hz. For the exact alignment with Fs 65 Hz, Qts 0.33 and Vas 21 l use the enclosure calculator at 42.audio.
How does the 10NTLW2500 differ from the B&C 10NDL88?
Both share a similar Qts of 0.32 to 0.33 and Fs around 65 Hz. The 10NDL88 has a stiffer suspension with Vas 15.6 l versus 21 l for the 10NTLW2500, which leads to slightly smaller boxes with less low-end extension.
At 42.audio you get the 18SOUND 10NTLW2500 with datasheet PDF, all key data in the driver database and the enclosure calculator. More drivers from this manufacturer: Atlas 18Sound.
Thiele-Small parameters
| Nominal impedance | 8 Ω |
|---|---|
| Resonance frequency fs | 65 Hz |
| Total Q Qts | 0.33 |
| Electrical Q Qes | 0.34 |
| Mechanical Q Qms | 11.2 |
| Equivalent volume Vas | 21.0 l |
| Moving mass Mms | 49.0 g |
| Cone area Sd | 346 cm² |
| Linear excursion Xmax | 7.6 mm |
| Force factor BL | 17.4 Tm |
| DC resistance Re | 5 Ω |
| Voice coil inductance Le | 0.45 mH |
Enclosure suggestion
The EBP of 191 suggests a bass-reflex enclosure. EBP = fs / Qes = 65 / 0.34
Sealed (Qtc 0.707)
- Enclosure volume Vb
- 5.8 l
- System resonance Fc
- 139 Hz
- Cut-off frequency F3
- 139 Hz
Bass reflex (QB3 after Small)recommended
- Enclosure volume Vb
- 10.8 l
- Tuning frequency Fb
- 80 Hz
- Cut-off frequency F3
- 87 Hz
Vb is the required net internal volume, Fb the tuning frequency of the reflex port and F3 the frequency at which the level has dropped by 3 dB. Calculated approximation after Small. A starting point for simulation, not a finished build plan.
Comparable drivers
Same size, same type, Qts within ±30 %.
- 18 Sound 10NTLW2500-8fs 65 Hz · Qts 0.33 · Vas 21 l · in the database
- FaitalPRO 10PR330fs 60 Hz · Qts 0.33 · Vas 32.5 l · in the database
- PRV Audio 10MB800FTfs 64.72 Hz · Qts 0.32 · Vas 36.73 l · in the database
- B&C Speakers 10NDL88fs 67 Hz · Qts 0.32 · Vas 15.6 l · in the database
- SB Audience NERO-10MWN600Dfs 68.1 Hz · Qts 0.34 · Vas 18.8 l · in the database
- FaitalPRO 10PR310fs 60 Hz · Qts 0.34 · Vas 32.2 l · in the database
Specifications
| Allgemein | |
|---|---|
| Manufacturer | 18SOUND |
| Category | Low Frequency |
| Series | NTLW |
| Magnet | Neo |
| Impedance (Ω) | 8 |
| Power handling (W) | 500 |
| Sensitivity (dB) | 96.5 |
| Frequency from (Hz) | 55 |
| Frequency to (Hz) | 4500 |
| Abmessungen & Korb | |
|---|---|
| Diameter | 10 |
| Voice coil (inch) | 2.5 |
| Mounting depth (mm) | 157 |
| Weight (kg) | 3.1 |
| Thiele-Small-Parameter | |
|---|---|
| Re (Ω) | 5 |
| Le (mH) | 0.45 |
| Fs (Hz) | 65 |
| Qms | 11.2 |
| Qes | 0.34 |
| Qts | 0.33 |
| Vas (l) | 21 |
| Xmax (mm) | 7.6 |
| BL (Tm) | 17.4 |
| Mms (kg) | 0.049 |
| Sd (m²) | 0.0346 |