18SOUND ND3SG
18SOUND (Eighteen Sound) ND3SG — 1.4" / 1.4 inch Compression Driver · Tweeter / HF Driver · Neodymium · Glass Dome
3" voice coil · 8/16 Ω
Part no.: 42A-CHS-KD-18S-0015
Documents
18Sound ND3SG: 1.4" compression driver with glass diaphragm and large neodymium motor
The ND3SG combines two features that otherwise appear separately in the ND series by 18Sound (Eighteen Sound): the glass diaphragm of the ND3G and the large magnet assembly of the S versions. The outcome is a 1.4" compression driver with a 3" voice coil, intended for applications where a neutral, well-damped treble has to meet high motor force – studio monitors with a low crossover point, for example, or demanding installations.
Glass as a diaphragm material is stiff and well damped at the same time. Where titanium shows its break-up resonances as narrow, tall peaks, glass spreads the energy wider and lower. The stronger motor of the S version provides more control over the diaphragm at the bottom of the working range, where the horn creates the highest load. The driver is available in 8 or 16 Ω.
Use and enclosure
As a 1.4" driver the ND3SG fits the 18Sound horns XT1464, XR1464C, XR1496C, PR614 and H860 3D Print as well as the XG14 Alu waveguide. For monitor and home use the waveguide is the obvious partner because it keeps coverage constant across frequency; for sound reinforcement you choose the horn by room and throw.
Set the crossover frequency according to the horn – well above the frequency from which the horn loads the driver, with a high-pass of at least 24 dB/octave. The large motor lets you get closer to the horn's lower limit than with the light version; a safety margin against misuse remains mandatory: limiter engaged, high-pass ahead of the power amp, never run without a horn.
What to look out for
- 8 or 16 Ω selectable – 16 Ω for parallel operation or passive crossovers with an attenuator.
- Glass diaphragm: never press on the dome when handling; replace the diaphragm only with the original part.
- Large neodymium magnet assembly – heavier than the ND3G, size the horn mounting accordingly.
- 1.4" throat with 3" coil – no adapters to 1" horns.
Frequently asked questions
ND3SG or ND3G?
Same glass diaphragm, same 3" coil, same 1.4" exit. The ND3SG has the larger motor and therefore more control at low crossover points and high levels; the ND3G is lighter. If you run the driver close to the horn's lower limit, take the SG.
Is glass suitable for live use?
Yes, as long as the electrical side is right. The diaphragm sits protected behind the phase plug; the dangers are low-frequency signals and transients, not sound pressure. With high-pass and limiter the ND3SG is a workhorse.
Which horn for studio monitors?
The XG14 Alu waveguide keeps directivity constant and is easy to equalise. If you need more directional control, take a horn such as the XR1496C. Both have the 1.4" throat of the ND3SG.
18Sound ND3SG: 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 ND3SG is a compression driver 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 ND3SG with all key data in the driver database. More drivers from this manufacturer: Atlas 18Sound.
Specifications
| Allgemein | |
|---|---|
| Manufacturer | 18SOUND |
| Category | Compression Driver |
| Series | ND |
| Magnet | Neodymium |
| Impedance (Ω) | 8/16 |
| Abmessungen & Korb | |
|---|---|
| Voice coil (inch) | 3 |