18SOUND 12ND940
18SOUND (Eighteen Sound) 12ND940 — 12" / 12 inch · Woofer/Midrange (WM) · Bass · Neodymium
3" voice coil · 8 Ω
Part no.: 42A-CHS-TT-18S-0064
Documents
18SOUND 12ND940 — 12" · Woofer
600 W AES · 100 dB Sensitivity · Frequency range 50 Hz – 3000 Hz
Technical data
- Diameter: 12 "
- Voice coil: 2.95 "
- Power handling: 600 W AES
- Sensitivity: 100 dB
- Impedance: 8 Ω
- Magnet: Neo
- Weight: 4.3 kg
- Mounting depth: 147 mm
- Frequency range: 50 – 3000 Hz
Datasheet (PDF) · Manufacturer page
Series: ND · Part no.: 42A-CHS-TT-18S-0064
18Sound 12ND940: 100 dB neodymium woofer with low inductance for mid-high systems
100 dB sensitivity from a 12" driver is the headline of the 18Sound 12ND940. The neodymium woofer from the ND series combines 600 W AES with a 2.95" voice coil, a 22.2 Tm motor and an inductance of just 0.57 mH – a figure that, on a 12" woofer, points to a shorting ring in the magnet system and gives very clean behaviour in the midrange.
With Fs 49 Hz, Qts 0.2 and Vas 64.8 l this is a classic high-efficiency motor: 66 g moving mass, 7.6 mm Xmax, 4.3 kg weight. The working range of 50 to 3,000 Hz shows the 12ND940 is not meant as a wide-band woofer but as a low-mid driver that is relieved by a subwoofer and delivers the fundamental range with punch.
Use and enclosure
The EBP of 245 is the highest in this 12" line-up and means: horn or small reflex box. The bass-reflex guideline is just under 9.6 l net tuned to 88 Hz with an f3 around 121 Hz. In a line-array element, a mid-high top over bass bins or the low-mid section of a 3-way box that is exactly right. Sealed, you are left with 5.6 l and a 173 Hz system resonance – a midrange chamber that works well in a 3-way system. The enclosure calculator on 42.audio runs both options with your real internal dimensions.
The 3,000 Hz upper limit and the low Le make the crossover to the tweeter straightforward, even passively. A 1.4" compression driver with a matching horn from 18Sound's Horns & Waveguides category is the natural partner when the crossover should sit low; with 1" drivers it moves up accordingly.
What to look out for
- 100 dB sensitivity: a lot of level per watt, the amplifier can stay small.
- Le 0.57 mH – small impedance rise, simple passive crossover.
- Qts 0.2 demands small boxes; bass-reflex guideline 9.6 l.
- Xmax 7.6 mm at 600 W AES – set a high-pass at the sub crossover.
- 4.3 kg, 147 mm mounting depth.
Frequently asked questions
What sets the 12ND940 apart from the B&C 12NDL76?
Both have a 50 Hz resonance and Qts 0.2, so the motors are laid out very similarly. The 12NDL76 has a slightly larger Vas of 73 l versus 64.8 l for the 12ND940. In the driver database on 42.audio you can put all parameters side by side.
Why does the 0.57 mH inductance matter so much?
A low Le keeps impedance flat through the midrange and reduces intermodulation, because inductance barely changes with voice-coil position. That is why the 12ND940 works cleanly up to 3,000 Hz and is easy to cross passively.
Which enclosure for a compact mid-high top?
A bass-reflex box around 9.6 l tuned to 88 Hz is the guideline. Below that you hand over to a subwoofer so the 7.6 mm excursion is not exceeded. Do the exact port design with the enclosure calculator on 42.audio.
18Sound 12ND940: manufacturer, spellings and classification
18Sound, 18 Sound and Eighteensound all refer to the same manufacturer: Eighteen Sound S.r.l. of Reggio Emilia, Italy. The 12ND940 is a 12-inch woofer with neodymium magnet from the ND series, available from 42.audio, 18Sound dealer in Germany, with datasheet and full specifications in the driver database.
At 42.audio you get the 18SOUND 12ND940 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 | 49 Hz |
| Total Q Qts | 0.2 |
| Electrical Q Qes | 0.2 |
| Mechanical Q Qms | 5.6 |
| Equivalent volume Vas | 64.8 l |
| Moving mass Mms | 66.0 g |
| Cone area Sd | 531 cm² |
| Linear excursion Xmax | 7.6 mm |
| Force factor BL | 22.2 Tm |
| DC resistance Re | 5 Ω |
| Voice coil inductance Le | 0.57 mH |
Comparable drivers
Same size, same type, Qts within ±30 %.
- B&C Speakers 12NDL76fs 50 Hz · Qts 0.2 · Vas 73 l · in the database
- 18 Sound 12ND710fs 52 Hz · Qts 0.2 · Vas 92 l · in the shop
- B&C Speakers 12NW100fs 44 Hz · Qts 0.2 · Vas 43.3 l · in the database
- B&C Speakers 12NW100fs 42 Hz · Qts 0.2 · Vas 44 l · in the database
- Beyma 12P80Fe/V2fs 48 Hz · Qts 0.21 · Vas 61 l · in the shop
- 18 Sound 12ND930fs 50 Hz · Qts 0.21 · Vas 70 l · in the shop
Specifications
| Allgemein | |
|---|---|
| Manufacturer | 18SOUND |
| Category | Low Frequency |
| Series | ND |
| Magnet | Neo |
| Impedance (Ω) | 8 |
| Power handling (W) | 600 |
| Sensitivity (dB) | 100 |
| Frequency from (Hz) | 50 |
| Frequency to (Hz) | 3000 |
| Abmessungen & Korb | |
|---|---|
| Diameter | 12 |
| Voice coil (inch) | 2.95 |
| Mounting depth (mm) | 147 |
| Weight (kg) | 4.3 |
| Thiele-Small-Parameter | |
|---|---|
| Re (Ω) | 5 |
| Le (mH) | 0.57 |
| Fs (Hz) | 49 |
| Qms | 5.6 |
| Qes | 0.2 |
| Qts | 0.2 |
| Vas (l) | 64.8 |
| Xmax (mm) | 7.6 |
| BL (Tm) | 22.2 |
| Mms (kg) | 0.066 |
| Sd (m²) | 0.0531 |