18SOUND 10NMBA520
18SOUND (Eighteen Sound) 10NMBA520 — 10" / 10 inch · Midrange with Lower Midrange (ML) · Midrange · Neodymium
2.5" voice coil · 8 Ω
Part no.: 42A-CHS-MT-18S-0020
Documents
18SOUND 10NMBA520 — 10" · Midrange Driver
300 W AES · 100.5 dB Sensitivity · Frequency range 60 Hz – 7000 Hz
Technical data
- Diameter: 10 "
- Voice coil: 2.5 "
- Power handling: 300 W AES
- Sensitivity: 100.5 dB
- Impedance: 8 Ω
- Magnet: Neo
- Weight: 3 kg
- Mounting depth: 104 mm
- Frequency range: 60 – 7000 Hz
Datasheet (PDF) · Manufacturer page
Series: NMBA · Part no.: 42A-CHS-MT-18S-0020
18Sound 10NMBA520: light 10" neodymium midrange with 100.5 dB and bandwidth to 7,000 Hz
From 60 to 7,000 Hz – hardly any 10" driver covers as much bandwidth as the 18Sound 10NMBA520. The lower limit comes from a resonance frequency of 60 Hz with Vas 42 l, the upper one from a light cone with 28 g moving mass. 100.5 dB sensitivity at 8 Ω, 300 W AES on a 2.5" coil and a neodymium motor with 3 kg total weight make it a candidate for anything that has to be light and still loud.
Qts 0.23 and Qes 0.24 indicate a motor with strong electrical damping, BL 14.6 Tm is moderate for a 10" neodymium driver – the 10NMBA520 lives less on brute force than on a very light moving assembly. Xmax of 4 mm is enough for low mids, and at 104 mm mounting depth it is one of the shallower 10" drivers.
Use and enclosure
The EBP of 250 points to bass-reflex or horn. Guideline for a reflex box: about 9.3 l tuned to 95 Hz with a lower cutoff around 122 Hz – compact enough for a three-way top in which the 10NMBA520 covers the range between bass and treble. Sealed it is about 5.0 l at a 184 Hz corner frequency, which serves as a midrange chamber when the high-pass sits well above the lower limit of 60 Hz anyway. Both are approximations; the exact design is what the enclosure calculator at 42.audio is for.
The bandwidth to 7,000 Hz allows a high crossover to the tweeter – interesting when a 1" driver on a small horn is used that you would rather spare from low crossover frequencies. With 300 W AES the thermal limit is clearly lower than with the 3" coils of the larger models, which makes a limiter sensible for continuous duty.
What to look out for
- 8 Ω, 100.5 dB: high efficiency, level matching to the bass in the crossover.
- 60–7,000 Hz: broadly usable, high crossover to the tweeter possible.
- 300 W AES on a 2.5" coil: plan a limiter for continuous duty.
- 3 kg, 104 mm mounting depth: light and shallow for neodymium tops.
- Xmax 4 mm, Fs 60 Hz: low mids in a bass-reflex box, no sub-bass.
Frequently asked questions
Which enclosure for the 10NMBA520?
Bass-reflex of about 9.3 l tuned to 95 Hz if you want to use the low mids; a sealed chamber around 5 l if it runs as a pure midrange. Both are guidelines derived from the TS parameters.
Can I combine it with a 1" compression driver?
Yes, and that is exactly where the bandwidth to 7,000 Hz helps: you can cross high and relieve the small driver. The matching horns and waveguides are in the 18Sound horns & waveguides category.
Which amplifier makes sense?
A channel around 300 W into 8 Ω covers the power handling; with 100.5 dB sensitivity you reach high SPL with considerably less. More important than power is a clean high-pass so the 4 mm Xmax is not eaten up by bass content.
18Sound 10NMBA520: 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 10NMBA520 is a 10-inch midrange driver with neodymium magnet from the NMBA 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 10NMBA520 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 | 60 Hz |
| Total Q Qts | 0.23 |
| Electrical Q Qes | 0.24 |
| Mechanical Q Qms | 4.2 |
| Equivalent volume Vas | 42.0 l |
| Moving mass Mms | 28.0 g |
| Cone area Sd | 350 cm² |
| Linear excursion Xmax | 4 mm |
| Force factor BL | 14.6 Tm |
| DC resistance Re | 5 Ω |
| Voice coil inductance Le | 0.01 mH |
Specifications
| Allgemein | |
|---|---|
| Manufacturer | 18SOUND |
| Category | Mid Frequency |
| Series | NMBA |
| Magnet | Neo |
| Impedance (Ω) | 8 |
| Power handling (W) | 300 |
| Sensitivity (dB) | 100.5 |
| Frequency from (Hz) | 60 |
| Frequency to (Hz) | 7000 |
| Abmessungen & Korb | |
|---|---|
| Diameter | 10 |
| Voice coil (inch) | 2.5 |
| Mounting depth (mm) | 104 |
| Weight (kg) | 3 |
| Thiele-Small-Parameter | |
|---|---|
| Re (Ω) | 5 |
| Le (mH) | 0.01 |
| Fs (Hz) | 60 |
| Qms | 4.2 |
| Qes | 0.24 |
| Qts | 0.23 |
| Vas (l) | 42 |
| Xmax (mm) | 4 |
| BL (Tm) | 14.6 |
| Mms (kg) | 0.028 |
| Sd (m²) | 0.035 |