18SOUND 8NTLW2500
18SOUND (Eighteen Sound) 8NTLW2500 — 8" / 8 inch · Midrange with Lower Midrange (ML) · Midrange · Neodymium · Dual-Gap
2x2.5" voice coil · 8/16 Ω
Part no.: 42A-CHS-MT-18S-0022
Documents
18Sound 8NTLW2500: 8" midrange with lower midrange and dual-gap motor with 2x2.5" voice coil
Within 18Sound's NTLW series, the 8NTLW2500 is the model with the larger coil: instead of 2x2", a 2x2.5" voice coil works in the dual-gap neodymium motor. Two separate windings run in two air gaps, giving the motor more wire in the field and dissipating heat across two cooling surfaces. The larger coil diameter raises thermal power handling and the stiffness of the former without a disproportionate increase in moving mass.
It is a midrange with lower midrange capability, meaning an 8" driver that does not start at a few hundred hertz but takes on the transition to the subwoofer. It is offered at 8 or 16 Ω, which keeps the choice open between a single driver at 8 Ω and two parallel 16 Ω drivers on one channel. The neodymium magnet keeps weight low, which can be decisive in flown systems.
Use and enclosure
Typical use is in line-array elements and compact tops, where one or two 8" drivers cover the range between subwoofer and compression driver. Whether sealed midrange chamber or vented box depends on the parameter set; no datasheet PDF is currently on file for the 8NTLW2500, so calculate with the values from our driver database in the enclosure calculator before building. For orientation: the 8NMB750 from the same manufacturer family sits at Fs 91 Hz, Qts 0.37 and Vas 7.3 l, a driver for very small volumes; the Beyma 8MI100 from our shop at Fs 90 Hz, Qts 0.45 and Vas 12 l.
The high-frequency side is handled by a compression driver; matching horns and waveguides from 18Sound are in the manufacturer's category. Important with two drivers per channel: choose the 16 Ω version, otherwise the amplifier ends up at 4 Ω.
What to look out for
- 8 or 16 Ω: choose the version by number of drivers per amplifier channel.
- 2x2.5" dual-gap voice coil: more thermal reserve than the 2x2" version.
- Neodymium motor: low weight, attractive for flown systems.
- No datasheet PDF on file: check TSP via the 42.audio driver database.
Frequently asked questions
How does the 8NTLW2500 differ from the model with the 2x2" coil?
In coil diameter and therefore in thermal power handling and motor force. The 2x2.5" coil has more wire in the field and more surface for heat dissipation. For the rest of the parameter set, our driver database is the place to look.
8 or 16 Ω, which version do I need?
One driver per channel: 8 Ω. Two drivers in parallel on one channel: 16 Ω, giving an 8 Ω load. With four drivers in series-parallel you are back at 8 Ω using 8 Ω drivers.
Which enclosure fits?
A midrange with lower midrange can run sealed or vented; as the midrange in a 3-way system you use a sealed chamber. The actual volume and tuning figures are calculated with the TSP from the database in our enclosure calculator, because no datasheet PDF is currently available for this model.
18Sound 8NTLW2500: 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 8NTLW2500 is a 8-inch midrange driver with neodymium magnet from the NTLW 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 8NTLW2500 with all key data in the driver database and the enclosure calculator. More drivers from this manufacturer: Atlas 18Sound.
Thiele-Small parameters
| Nominal impedance | 16 Ω |
|---|---|
| Resonance frequency fs | 80 Hz |
| Total Q Qts | 0.38 |
| Electrical Q Qes | 0.39 |
| Mechanical Q Qms | 9.9 |
| Equivalent volume Vas | 7.2 l |
| Moving mass Mms | 40.0 g |
| Cone area Sd | 227 cm² |
| Linear excursion Xmax | 7.6 mm |
| Force factor BL | 22.9 Tm |
| DC resistance Re | 10.3 Ω |
| Voice coil inductance Le | 0.68 mH |
Comparable drivers
Same size, same type, Qts within ±30 %.
- PRV Audio 8MR600Xfs 76.9 Hz · Qts 0.4 · Vas 19.99 l · in the database
- 18 Sound 8NMB750fs 91 Hz · Qts 0.37 · Vas 7.3 l · in the database
- PRV Audio 8MR600X-4fs 77.22 Hz · Qts 0.34 · Vas 19.65 l · in the database
- PRV Audio 8MR500-4 BULLETfs 78.2 Hz · Qts 0.46 · Vas 20.8 l · in the database
- Beyma 8MI100fs 90 Hz · Qts 0.45 · Vas 12 l · in the shop
- PRV Audio 8MR600X-NDYfs 87.6 Hz · Qts 0.29 · Vas 12.58 l · in the database
Specifications
| Allgemein | |
|---|---|
| Manufacturer | 18SOUND |
| Category | Mid Frequency |
| Series | NTLW |
| Magnet | Neodymium |
| Impedance (Ω) | 8/16 |
| Abmessungen & Korb | |
|---|---|
| Diameter | 8 |
| Voice coil (inch) | 2x2.5 |