CELESTION CF1840JD
CELESTION CF1840JD — 18" / 18 Zoll · Tieftöner · Ferrit
1200 W AES - 97 dB - 30 – 2500 Hz - 8 Ω
Art.-Nr.: 42A-CHS-TT-CEL-0010
Documents
CELESTION CF1840JD — 18" · Woofer
18-inch, cast aluminium chassis, ferrite magnet LF driver
1200 W AES · 97 dB Sensitivity · Frequency range 30 Hz – 2500 Hz
Features
- Balanced airflow venting provides enhanced cooling
- Twin demodulation rings
- Optimised double suspension
Technical data
- Diameter: 18 "
- Voice coil: 4 "
- Power handling: 1200 W
- Programme power: 2400W
- Sensitivity: 97 dB
- Impedance: 8 Ω
- Magnet: Ferrite
- Chassis: Cast aluminium
- Diaphragm: Kevlar-reinforced paper
- Surround: Cloth-sealed
- Suspension: Double
- Voice coil former: Glass fibre
- Voice coil wire: Copper, round wire
- Weight: 11.6 kg
- Mounting depth: 220 mm
- Cut-out: 414mm / 16.24in
- Frequency range: 30 – 2500 Hz
Thiele-Small parameters
- Fs: 37 Hz
- Qts: 0.397
- Qms: 4.372
- Qes: 0.437
- Vas: 155 l
- Xmax: 12.5 mm
- BL: 24.76 Tm
- Re: 5.29 Ω
- Le: 1.16 mH
- Mms: 0.2174 kg
- Sd: 0.1134 m²
Datasheet (PDF) · Manufacturer page
Part no.: 42A-CHS-TT-CEL-0010
Celestion CF1840JD: 18" woofer with 12.5 mm Xmax and 1200 W AES for subwoofers
The Celestion CF1840JD is the CF series' 18" woofer for subwoofers and large bass cabinets: 1200 W AES on a 4" round copper wire voice coil on a glass-fibre former, 97 dB at 8 Ω, rated band 30 to 2500 Hz. The Kevlar-loaded paper cone sits in a cloth-sealed surround, the double suspension keeps the coil on track at 12.5 mm Xmax, and twin demodulation rings reduce distortion at high currents. The ferrite magnet in the cast aluminium frame uses balanced airflow venting.
The parameters: Fs 37 Hz, Qts 0.397, Vas 155 l, 217.4 g of moving mass and a 24.76 Tm motor on 0.1134 m² of cone area. The EBP of 85 is what sets this driver apart: it sits in the range where vented and sealed enclosures both work sensibly. That makes the CF1840JD more flexible than most PA 18" drivers, which only convince in a reflex box.
Use and enclosure
The vented guideline is 164 l tuned to 36 Hz with a cut-off around 35 Hz. That is a full-grown subwoofer reaching the lower edge of the rated band. If you need a smaller cabinet, build sealed: about 71 l with a 66 Hz in-box resonance gives a compact, punchy sub that can be pulled lower with equalisation, since 12.5 mm Xmax provides the reserve for it. Both variants can be adapted to your volume with the enclosure calculator at 42.audio.
In subwoofer duty you cross low to the top cabinet; the upper rated limit of 2500 Hz is generously specified for an 18" but plays no role in practice, because the large cone beams strongly in the midrange. For cabinet building and transport, allow for 220 mm mounting depth, a 414 mm cut-out and 11.6 kg; for an 18" with 1200 W AES that weight is moderate.
What to look out for
- EBP 85: vented 164 l or sealed 71 l, both sensible as guidelines.
- Xmax 12.5 mm with double suspension: excursion reserve for low tunings.
- 1200 W AES on a 4" coil, ferrite magnet with balanced airflow venting.
- Twin demodulation rings, Le 1.16 mH.
- 220 mm deep, 414 mm cut-out, 11.6 kg.
Frequently asked questions
Vented or sealed for the CF1840JD?
Both work, which is the strength of this driver at an EBP of 85. Vented at 164 l tuned to 36 Hz delivers maximum extension and level, sealed at about 71 l gives a much smaller, punchy cabinet whose extension you can supplement with equalisation and the 12.5 mm of excursion.
How low does the CF1840JD go?
In the 164 l vented guideline the cut-off is around 35 Hz, close to the lower edge of the 30 Hz rated band. Sealed, the in-box resonance is 66 Hz, below which the level rolls off gently and can be boosted electronically.
Which amplifier does the driver need?
An amplifier around the AES rating of 1200 W into 8 Ω; at 97 dB that gets you high subwoofer levels. A high-pass below the tuning frequency and a limiter protect excursion and coil in continuous use.
Celestion CF1840JD: manufacturer, spellings and classification
Celestion is the British loudspeaker manufacturer Celestion International Ltd. of Ipswich, England; its PA drivers are also known as Celestion Pro Audio. The CF1840JD is a 18-inch woofer with ferrite magnet from the CF series, available from 42.audio, Celestion dealer in Germany, with datasheet and full specifications in the driver database.
At 42.audio you get the CELESTION CF1840JD with all key data in the driver database and the enclosure calculator. More drivers from this manufacturer: Atlas Celestion.
Specifications
| Allgemein | |
|---|---|
| Manufacturer | CELESTION |
| Category | Low Frequency |
| Series | CF |
| Magnet | Ferrite |
| Impedance (Ω) | 8 |
| Power handling (W) | 1200 |
| Sensitivity (dB) | 97 |
| Frequency from (Hz) | 30 |
| Frequency to (Hz) | 2500 |
| Abmessungen & Korb | |
|---|---|
| Diameter | 18 |
| Voice coil (inch) | 4 |
| Mounting depth (mm) | 220 |
| Weight (kg) | 11.6 |
| Thiele-Small-Parameter | |
|---|---|
| Re (Ω) | 5.29 |
| Le (mH) | 1.16 |
| Fs (Hz) | 37 |
| Qms | 4.372 |
| Qes | 0.437 |
| Qts | 0.397 |
| Vas (l) | 155 |
| Xmax (mm) | 12.5 |
| BL (Tm) | 24.76 |
| Mms (kg) | 0.2174 |
| Sd (m²) | 0.1134 |