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Beyma · LX60 Series

Beyma 18LX60

Beyma 18LX60: discontinued 18″ subwoofer driver with ferrite motor, 4″ copper voice coil and Fs 27 Hz – predecessor of the 18LX60V2/S.

Discontinued · Last checked: 2026-11-13

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Schematic cross-section: 18″ driver with ferrite motor Side section: on the left the motor with a large ferrite ring magnet, pole piece and top plate with the air gap. The voice coil sits in the gap on its former, held by the spider. To the right the cone opens out with its dust cap, with the surround at the edge of the basket. The drawing shows the construction, not the dimensions of a particular model.
Schematic cross-section of a driver with a ferrite motor. The drawing shows the construction, not the dimensions of this model; the manufacturer has a product photo.

General data

Link to section “General data”
Type
Subwoofer driver
Nominal size
18″
Nominal impedance
8 Ω Manufacturer
Minimum impedance
7.1 Ω Manufacturer
Sensitivity
98 dB 2.83 V / 1 m · half space (2π) Manufacturer
Frequency range
25 Hz – 1,000 Hz Manufacturer
Voice coil Ø
100 mm Manufacturer
Winding height
23 mm Manufacturer
Gap depth
9.5 mm Manufacturer
Flux density
not available
Magnet
ferrite
Weight
11.5 kg Manufacturer
Baffle cut-out Ø
415 mm Front mounting. For rear mounting Beyma states 425 mm. Manufacturer
Overall diameter
460 mm Manufacturer
Mounting depth
195 mm Manufacturer
Displacement
13 L Manufacturer
Recommended enclosure volume
80 – 250 L Manufacturer

Beyma measures the Thiele-Small parameters after preconditioning, using a laser measurement method; according to the datasheet they represent the long-term values after a short period of operation. The simulated low-bass curve in the datasheet applies to a 150 L bass reflex enclosure with 30 Hz tuning.

Voice coil of edge-wound flat copper wire, paper cone. Beyma gives 80 to 250 L as the enclosure volume. The product page lists the driver as discontinued and names the 18LX60V2/S as its replacement; its parameters differ considerably, so it is not an identical successor.

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.

Bass reflex Sealed Calculated

The EBP is between 50 and 100 – by the rule of thumb, both a bass reflex and a sealed enclosure are possible. This is based on an EBP of 71.1.

Net volume
540 L
Tuning frequency
28.5 Hz
F3 (−3 dB)
26.6 Hz
F6 (−6 dB)
24.1 Hz
F10 (−10 dB)
21.4 Hz
Sensitivity (2.83 V / 1 m)
97.8 dB
Max. SPL at 26.6 Hz
120.7 dB
Max. SPL at 53.3 Hz
122 dB
Xmax limits below
72.8 Hz
Ports
1 × 400 mm
Port area for 17 m/s
837 cm²
Max. port velocity
11.3 m/s
Port length
56.3 cm
1020501002005001k708090100110120130Frequency (Hz)Level (dB SPL)
  • at 700 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.

Open in the designer

Thiele-Small parameters

Link to section “Thiele-Small parameters”

Small-signal parameters as stated by the manufacturer. They change with temperature and level.

Fs
27 Hz
Re
5.5 Ω
Le
1.2 mH (at 1,000 Hz)
Qts
0.37
Qes
0.38
Qms
11.45
Vas
500 L
BL
20.5 T·m
Mms
172 g
Cms
0.202 mm/N
Sd
1,320 cm²
Xmax
9 mm
Xdamage
40 mm
Vd
1.2 L
EBP
not available
Efficiency η₀
2.5 %

Plausibility check

Link to section “Plausibility check”

We recalculate dependent values from the datasheet. We flag deviations above 3 %.

Recalculated parameters
CheckFormula DatasheetCalculatedResult
Qts from Qes and Qms Qts = Qes · Qms / (Qes + Qms) 0.37 0.368 consistent
Vd from Sd and Xmax Vd = Sd · Xmax 1.2 1.188 consistent
Xmax, geometric Xmax = (winding height − gap depth) / 2 9 6.75 different definition

Manufacturers define Xmax differently. A deviation from the purely geometric formula is not an error, but shows that a different definition was used.

Power handling

Link to section “Power handling”
  • AES700 W
  • Programme power1,400 W

According to the datasheet, power handling is determined according to AES2-1984 (r2003). Beyma describes programme power as the ability to handle normal music material.

Build plans with this driver

Link to section “Build plans with this driver”

Sources

Link to section “Sources”
  1. Tier A · primary source

    Beyma 18LX60 – Datasheet (PDF, 2 pages)

    Acústica Beyma S.L.U. · September 2005 (Date from file metadata) · accessed on 13 November 2026

    No date in the document; the PDF metadata creation date is 1 September 2005. Linked from the manufacturer’s product page (“Download datasheet”). Datasheet of the first version, not of the successor 18LX60V2/S.

  2. Tier A · primary source

    Beyma 18LX60 (8 Ω) – Product page (eingestellte Produkte)

    Acústica Beyma S.L.U. · accessed on 13 November 2026

    The page is in the “Discontinued products” section and carries the notice “This product is discontinued”; Beyma names the 18LX60V2/S as a replacement. It contains no technical data but links the datasheet.

  3. Tier A · primary source

    Speakerplans.com – C Sub – Coupled Cavity Enclosure

    Rog Mogale · Speakerplans.com · 2000 · accessed on 13 September 2026

    According to the drawing, up to four enclosures may be built; anyone who wants to make money with them should ask the designer for a licence.