18SOUND 12W500
18SOUND (Eighteen Sound) 12W500 — 12" / 12 inch · Midrange with Lower Midrange (ML) · Midrange · Ferrite
2.5" voice coil · 8 Ω
Part no.: 42A-CHS-MT-18S-0003
Documents
18SOUND 12W500 — 12" · Midrange Driver
350 W AES · 99.5 dB Sensitivity · Frequency range 50 Hz – 6000 Hz
Technical data
- Diameter: 12 "
- Voice coil: 2.5 "
- Power handling: 350 W AES
- Sensitivity: 99.5 dB
- Impedance: 8 Ω
- Magnet: Ferrite
- Weight: 5.2 kg
- Mounting depth: 141 mm
- Frequency range: 50 – 6000 Hz
Datasheet (PDF) · Manufacturer page
Series: W · Part no.: 42A-CHS-MT-18S-0003
18Sound 12W500: 12" ferrite mid-woofer with 99.5 dB for tops reaching 50 Hz
The 12W500 from the W series by 18Sound (Eighteen Sound) is the ferrite answer to the search for a forgiving 12" mid-woofer: 350 W AES, 99.5 dB sensitivity, a 2.5" voice coil and an operating range of 50 Hz to 6,000 Hz. At 5.2 kg it weighs more than its neodymium siblings, but the motor stays thermally stable and the cost stays reasonable – a solid argument for DIY builders and small production runs.
The Qts of 0.36 is worth noting. Together with Fs 46 Hz, Vas 123 l and BL 12.1 Tm it describes a driver not tuned for maximum motor strength but for a balanced alignment that plays low in ordinary bass reflex boxes without tricks. The moving mass of 36.5 g is light for a 12" driver and explains why sensitivity reaches 99.5 dB despite the moderate motor.
Use and enclosure
As the midrange in a three-way cabinet the 12W500 runs in a sealed midrange chamber, for which the guideline suggests 43 l with a system resonance of 90 Hz – a comparatively large chamber, explained by the compliant suspension and high Vas. More interesting is its use as a mid-woofer in a two-way top: the bass reflex guideline is 98 l tuned to 48 Hz, with f3 around 50 Hz. For a 12" driver without a subwoofer that is deep, and it makes the 12W500 a candidate for full-range cabinets, stage monitors with substance and high-efficiency home cinema projects. The EBP of 121 sits near the boundary where sealed and vented both work; the enclosure calculator on 42.audio shows what each volume delivers.
The upper limit of 6,000 Hz leaves room for a crossover to a 1" compression driver, sensibly well below that. Xmax of 4 mm sets the limit for low-frequency level – if you want loud and deep at the same time, add a high-pass and a subwoofer.
What to look out for
- 8 Ω, Re 5.2 Ω: an easy load; a 4 Ω variant is listed as well.
- Ferrite magnet: 5.2 kg, but robust under sustained load and cheaper than neodymium.
- Mounting depth 141 mm – the ferrite motor needs room behind the baffle.
- Xmax 4 mm in a 98 l reflex volume: a high-pass below 48 Hz protects against over-excursion.
- Qts 0.36 and Vas 123 l: tolerates larger enclosures, not intended for tiny boxes.
Frequently asked questions
Can I build a full-range cabinet without a subwoofer using the 12W500?
Yes, that is its strength. In the 98 l bass reflex guideline tuned to 48 Hz, the lower cutoff sits around 50 Hz. Bass level stays limited by the 4 mm Xmax, which is enough for speech, acoustic music and moderate playback levels.
Which amplifier suits the 12W500?
A channel of roughly 350 W into 8 Ω covers the AES rating. With 99.5 dB sensitivity the driver reaches high levels on less power, and the decisive element is a high-pass filter keeping signals below the tuning frequency away.
How does the 12W500 compare to the FaitalPRO 12PR300?
Both share Qts 0.36 with Fs at 50 Hz and 46 Hz respectively, and the 12PR300 with 92.6 l Vas ends up in a somewhat smaller box than the 12W500 with 123 l. In practice both suit similar reflex designs; the driver database on 42.audio shows the parameters side by side.
At 42.audio you get the 18SOUND 12W500 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 | 46 Hz |
| Total Q Qts | 0.36 |
| Electrical Q Qes | 0.38 |
| Mechanical Q Qms | 6.02 |
| Equivalent volume Vas | 123.0 l |
| Moving mass Mms | 36.5 g |
| Cone area Sd | 531 cm² |
| Linear excursion Xmax | 4 mm |
| Force factor BL | 12.1 Tm |
| DC resistance Re | 5.2 Ω |
| Voice coil inductance Le | 1.12 mH |
Enclosure suggestion
The EBP of 121 suggests a bass-reflex enclosure. EBP = fs / Qes = 46 / 0.38
Sealed (Qtc 0.707)
- Enclosure volume Vb
- 43.1 l
- System resonance Fc
- 90 Hz
- Cut-off frequency F3
- 90 Hz
Bass reflex (QB3 after Small)recommended
- Enclosure volume Vb
- 84.5 l
- Tuning frequency Fb
- 52 Hz
- Cut-off frequency F3
- 54 Hz
Vb is the required net internal volume, Fb the tuning frequency of the reflex port and F3 the frequency at which the level has dropped by 3 dB. Calculated approximation after Small. A starting point for simulation, not a finished build plan.
Comparable drivers
Same size, same type, Qts within ±30 %.
- FaitalPRO 12PR300fs 50 Hz · Qts 0.36 · Vas 92.6 l · in the database
- FaitalPRO 12FH500fs 48 Hz · Qts 0.37 · Vas 77.4 l · in the database
- FaitalPRO 12PR320fs 42 Hz · Qts 0.37 · Vas 113.3 l · in the database
- FaitalPRO 12RS550fs 42 Hz · Qts 0.37 · Vas 45.4 l · in the database
- B&C Speakers 12PLB100fs 50 Hz · Qts 0.37 · Vas 47 l · in the database
- B&C Speakers 12NDL88fs 50 Hz · Qts 0.37 · Vas 55 l · in the database
Specifications
| Allgemein | |
|---|---|
| Manufacturer | 18SOUND |
| Category | Mid Frequency |
| Series | W |
| Magnet | Ferrite |
| Impedance (Ω) | 8 |
| Power handling (W) | 350 |
| Sensitivity (dB) | 99.5 |
| Frequency from (Hz) | 50 |
| Frequency to (Hz) | 6000 |
| Abmessungen & Korb | |
|---|---|
| Diameter | 12 |
| Voice coil (inch) | 2.5 |
| Mounting depth (mm) | 141 |
| Weight (kg) | 5.2 |
| Thiele-Small-Parameter | |
|---|---|
| Re (Ω) | 5.2 |
| Le (mH) | 1.12 |
| Fs (Hz) | 46 |
| Qms | 6.02 |
| Qes | 0.38 |
| Qts | 0.36 |
| Vas (l) | 123 |
| Xmax (mm) | 4 |
| BL (Tm) | 12.1 |
| Mms (kg) | 0.0365 |
| Sd (m²) | 0.0531 |