Precision Devices PD.185N02
18″ driver from Precision Devices with neodymium motor and high BL – datasheet values from the horn build plan PD-H118A.
Availability not checked · Last checked: 2026-09-13
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General data
Link to section “General data”- Type
- Subwoofer driver
- Nominal size
- 18″
- Nominal impedance
- 8 Ω Manufacturer
- Minimum impedance
- not available
- Sensitivity
- 98 dB 1 W / 1 m Manufacturer
- Frequency range
- 35 Hz – 1,000 Hz Manufacturer
- Voice coil Ø
- 127 mm Manufacturer
- Winding height
- not available
- Gap depth
- not available
- Flux density
- 1.18 T Manufacturer
- Magnet
- neodymium
- Weight
- not available
- Baffle cut-out Ø
- 414 mm Cutout according to the baffle drawing of the manufacturer's build plan. The product page gives a basket shoulder diameter of 414.5 mm. The cutout in the plan is therefore smaller than the basket shoulder – measure on the driver before routing. Manufacturer
- Overall diameter
- 474 mm Manufacturer
- Mounting depth
- 200 mm Sum of the depth without flange (185 mm) and the flange height (14.5 mm), both according to the product page. Manufacturer
- Displacement
- not available
- Recommended enclosure volume
- 90 – 220 L Manufacturer
The datasheet additionally gives L2 = 1.5 mH and R2 = 60.87 Ω.
What can this driver do?
Link to section “What can this driver do?”Simulation from the datasheet values above. The suggestions are calculated, not stated by the manufacturer.
The EBP is above 130 – by the rule of thumb, this points to a vented enclosure and also makes the driver interesting for horns. This is based on an EBP of 141.
- Net volume
- 70.5 L
- Tuning frequency
- 57 Hz
- F3 (−3 dB)
- 55.5 Hz
- F6 (−6 dB)
- 50 Hz
- F10 (−10 dB)
- 44.2 Hz
- Sensitivity (2.83 V / 1 m)
- 99.3 dB
- Max. SPL at 55.5 Hz
- 126.7 dB
- Max. SPL at 111 Hz
- 129.5 dB
- Xmax limits below
- 42.4 Hz
- Ports
- 2 × 160 mm
- Port area for 17 m/s
- 565 cm²
- Max. port velocity
- 23.9 m/s
- Port length
- 40.7 cm
- at 1,100 W
- Maximum SPL (limited by Xmax)
- Power into 8 Ω (nominal impedance of the wiring).
- Flattest alignment: lowest F3 without the response rising more than 0.25 dB above the passband level or dropping more than 0.5 dB at 2 × F3.
- The 17 m/s limit (about 5 % of the speed of sound) is a common rule of thumb against port noise, not a standard. Rounded port ends allow higher values.
- Lumped-element Thiele/Small model, Half space, 1 m, chamber losses QL 7, Le as a plain inductance, no room influence. At high levels (heating, non-linear Bl and Cms) real results are lower.
Thiele-Small parameters
Link to section “Thiele-Small parameters”Small-signal parameters as stated by the manufacturer. They change with temperature and level.
Plausibility check
Link to section “Plausibility check”We recalculate dependent values from the datasheet. We flag deviations above 3 %.
| Check | Formula | Datasheet | Calculated | Result |
|---|---|---|---|---|
| Qts from Qes and Qms | Qts = Qes · Qms / (Qes + Qms) | 0.24 | 0.247 | consistent |
| Vd from Sd and Xmax | Vd = Sd · Xmax | 1.397 | 1.397 | consistent |
Power handling
Link to section “Power handling”- AES1,100 W
- Peak power4,400 W
Sources disagree: Xmax
- 12 – PDF p. 3 (“Xmax 12 mm / 22 mm”) Adopted
- 22 – PDF p. 3 (“Xmax 12 mm / 22 mm”)
The datasheet gives two values without explanation. We adopt 12 mm because the stated Vd = 1.397 L corresponds exactly to Sd · 12 mm. The second figure could describe a different limit; the datasheet does not say.
Build plans with this driver
Link to section “Build plans with this driver”Sources
Link to section “Sources”-
Tier A · primary source
PD-H118A – 18” Horn-Loaded Subwoofer (build plan PDF)
Precision Devices International Ltd. · 2017 · accessed on 13 September 2026
Printed © 2017, drawings revision 1.0. Free for non-commercial use.
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Tier A · primary source
Precision Devices PD.185N02 – Product page
Precision Devices International Ltd. · accessed on 13 November 2026