B&C design
S218BP
2x18" 6800w 6th Order Band Pass Subwoofer
- Drivers
- 2 × 18DS115, 8 Ω
- Output
- 139 dB peak, CEA-2010B
- Power
- 6,800 W
18-inch LF driver · 18DS series · 116 mm voice coil · 1,700 W
B&C 18DS115 8Ω
30–500 Hz
£448.36
SteadyJP Leisure · In stock · All 14 offers
- Fs
- 30Hz
- Xmax
- 16.5mm
- SPL
- 95dB
- Pe
- 1700W
- BL
- 39T·m
- Vd
- 1997cm³
- Qts
- 0.20
- Vas
- 168L
Published graphs
B&C 18DS115 is an 18-inch 8 ohm LF driver rated at 1700 W RMS. The validated T/S data includes Fs 30 Hz, Qts 0.20, Vas 168 L, Xmax 16.5 mm, sensitivity 95.4 dB, plus 1997 cm³ Vd and 143 EBP. bits tracks UK, EU and US shop prices, price movement, datasheet links, simulator import data, and similar drivers, with a current best price of £431.10.
The published T/S values agree with each other
Thiele/Small
- Fs
- 30Hz
- Qts
- 0.20
- Qes
- 0.21
- Qms
- 4.3
- Vas
- 168L
- Re
- 5Ω
- Le
- 3.85mH
Motor and cone
- BL
- 39T·m
- Sd
- 1210cm²
- Mms
- 330g
- Xmax
- 16.5mm
- Vd †
- 1997cm³
- Voice coil
- 116mm
- Flux density
- 0.80T
Power and response
- Sensitivity †
- 95.4dB
- Manufacturer sensitivity
- 98dB
- Power
- 1700W
- Nominal power
- 1700W
- Impedance
- 8Ω
- Min. impedance
- 7Ω
- Range
- 30–500Hz
- EBP †
- 143 · Leans vented
Size and mounting
- Diameter
- 460mm
- Cutout
- 425mm
- Bolt circle
- 442mm
- Depth
- 248mm
- Weight
- 12.6kg
Sensitivity shows 95.4 dB, calculated from the T/S values. B&C publishes 98.0 dB, 2.6 dB apart.
† Calculated by bits from the published values
What this validation status means
Everything else B&C lists
LF
- BL
- 39T·m
- Fs
- 30Hz
- Le
- 3.85mH
- Re
- 5Ω
- Sd
- 1210cm²
- Mms
- 330g
- Qes
- 0.21
- Qms
- 4.3
- Qts
- 0.20
- SPL
- 95.4dB
- Vas
- 168L
- Xmax
- 16.5mm
- Power
- 1700W
- Impedance
- 8Ω
- Flux density
- 0.80T
- Sensitivity
- 98dB
- Low limit
- 30Hz
- Nominal power
- 1700W
- Calculated sensitivity †
- 95.4dB
- High limit
- 500Hz
- Manufacturer sensitivity
- 98dB
- Min. impedance
- 7Ω
- Voice coil
- 116mm
- Weight
- 12.6kg
- Diameter
- 460mm
- Depth
- 248mm
- Cutout
- 425mm
- Bolt circle
- 442mm
- Bl
- 39 Tm
- Fs
- 30 Hz
- Le
- 3.85 mH
- Re
- 5 Ω
- Sd
- 1210 cm² (187.55 in²)
- Ebp
- 143 Hz
- Mms
- 330 g
- Qes
- 0.21
- Qms
- 4.3
- Qts
- 0.2
- Vas
- 168 dm³ (5.93 ft³)
- Η0
- 2.2 %
- Cone
- RCK18DS1158
- Xmax
- 16.5 mm
- Xvar
- 14 mm
- Depth
- 248 mm (9.76 in)
- Spider
- Double Silicone
- Cone shape
- Radial
- Net weight
- 12.55 kg (27.67 lb)
- Pole design
- T-Pole
- Sensitivity
- 98 dB
- Flux density
- 0.8 T
- Shipping box
- 500x495x275 mm (19.69x19.49x10.83 in)
- Winding depth
- 40 mm (1.57 in)
- Shipping units
- 1 pcs
- Surround shape
- Triple Roll
- Former material
- Glass Fibre
- Frequency range
- 30 Hz - 500 Hz
- Magnet material
- Neodymium Inside Slug
- Shipping weight
- 14.15 kg (31.2 lb)
- Nominal diameter
- 460 mm (18 in)
- Overall diameter
- 460 mm (18 in)
- Winding material
- Aluminium
- Minimum impedance
- 7 Ω
- Nominal impedance
- 8 Ω
- Magnetic gap depth
- 14 mm (0.55 in)
- Recommended tuning
- 40 Hz
- Voice coil diameter
- 116 mm (4.5 in)
- Bolt circle diameter
- 442 mm (17.4 in)
- Recommended enclosure
- 100 dm³ (3.53 ft³)
- Woofer cone treatment
- TWP Waterproof Both Sides
- Baffle cutout diameter
- 425 mm (16.73 in)
- Nominal power handling
- 1700 W
- Continuous power handling
- 3400 W
- Flange and gasket thickness
- 16 mm (0.63 in)
- Air volume occupied by driver
- 10 dm³ (0.35 ft³)
02
Designs
Cabinets for the 18DS115: two designs and a suggested box from B&C, plans builders have published, and flatpack kits of the S218BP.
All 18DS115 designsHow we find designsB&C’s designs
From the maker, with plans to download
Cut in the UK
B&C design
S21IB
Extended LF Reflex Isobaric Subwoofer
- Drivers
- 2 × 18DS115, 8 Ω1 × 21DS115, 8 Ω
B&C’s suggested box
From B&C’s 18DS115 page
- Net volume
- 100L
- Tuning
- 40Hz
B&C gives the volume and tuning; the port is sized for the driver when you open it.
Modelling the box in 00 Simulator…
Plans from builders
Links to published plans that name this driver
HOQS’s own simulation uses the 18DS115-4
The designer calls it “a step up”, needing 2,000–3,000 W per driver
03
Compare
Same-size drivers, compared with the 18DS115. Clear differences are green when better and red when worse.
This driver18DS115
Best price
£431.10
Fs
30 Hz
Qts
0.20
Vas
168 L
BL
39 T·m
Xmax
16.5 mm
Sensitivity
95.4 dB
Power
1700 W
REDCATT182FIND
£201.58 · 53% less, betterFs31 Hz +3%
Qts0.23 +15%, worse
Vas208.6 L +24%, worse
BL35.4 T·m −9%
Xmax5.8 mm −65%, worse
Sensitivity96.2 dB +0.8
Beyma18QLEX1600FE
£299.00 · 31% less, betterFs30 Hz –
Qts0.23 +15%, worse
Vas195 L +16%, worse
BL36.4 T·m −7%
Xmax13 mm −21%, worse
Sensitivity95.4 dB –
Eighteen Sound18LW2600
£300.67 · 30% less, betterFs31 Hz +3%
Qts0.29 +45%, worse
Vas187 L +11%, worse
BL31 T·m −21%, worse
Xmax14.8 mm −10%, worse
Sensitivity94.7 dB −0.7
B&C18DS100
£350.64 · 19% less, betterFs34 Hz +13%, worse
Qts0.29 +45%, worse
Vas155 L −8%
BL30 T·m −23%, worse
Xmax14.5 mm −12%, worse
Sensitivity95.1 dB –
Precision DevicesPD.185C003
£366.00 · 15% less, betterFs33 Hz +10%, worse
Qts0.24 +20%, worse
Vas224 L +33%, worse
BL31.5 T·m −19%, worse
Xmax11 mm −33%, worse
Sensitivity97.5 dB +2.1, better
Eighteen Sound18NLW4100
£376.05 · 13% less, betterFs31 Hz +3%
Qts0.34 +70%, worse
Vas180 L +7%
BL29 T·m −26%, worse
Xmax15 mm −9%
Sensitivity93.9 dB −1.5
CelestionTSQ1845
£385.36 · 11% less, betterFs35 Hz +17%, worse
Qts0.29 +45%, worse
Vas119.3 L −29%, better
BL33.8 T·m −13%, worse
Xmax15 mm −9%
Sensitivity94.3 dB −1.1
SB AudienceNERO-18SW1900D
£398.03 · 8% less, betterFs34 Hz +13%, worse
Qts0.42 +110%, worse
Vas157.9 L −6%
BL28.5 T·m −27%, worse
Xmax17.5 mm +6%
Sensitivity93.6 dB −1.8
FaitalPRO18XL2000
£420.00 · 3% lessFs28 Hz −7%
Qts0.27 +35%, worse
Vas232.1 L +38%, worse
BL30.8 T·m −21%, worse
Xmax16.3 mm –
Sensitivity94.6 dB −0.8
RCFLN19S400
£421.78 · 2% lessFs32 Hz +7%
Qts0.26 +30%, worse
Vas204 L +21%, worse
BL32 T·m −18%, worse
Xmax17 mm +3%
Sensitivity96 dB +0.6
No photo
Precision DevicesPD.1845-2N
£427.00 · Same priceFs35 Hz +17%, worse
Qts0.39 +94%, worse
Vas157 L −7%
BL27 T·m −31%, worse
Xmax18 mm +9%
Sensitivity94.3 dB −1.1
B&C18SW115
£435.33 · Same priceFs32 Hz +7%
Qts0.30 +50%, worse
Vas187 L +11%, worse
BL30.3 T·m −22%, worse
Xmax14 mm −15%, worse
Sensitivity94.9 dB −0.5
Eighteen Sound18NLW4500
£474.29 · 10% more, worseFs35 Hz +17%, worse
Qts0.33 +65%, worse
Vas151 L −10%, better
BL30.3 T·m −22%, worse
Xmax15.3 mm −7%
Sensitivity94.8 dB −0.6
FaitalPRO18XL1700
£475.00 · 10% more, worseFs28 Hz −7%
Qts0.28 +40%, worse
Vas227 L +35%, worse
BL30.5 T·m −22%, worse
Xmax16.2 mm –
Sensitivity94.4 dB −1
EminenceNSW4018-8
£527.89 · 22% more, worseFs36 Hz +20%, worse
Qts0.38 +90%, worse
Vas164.5 L –
BL28.2 T·m −28%, worse
Xmax15.2 mm −8%
Sensitivity95 dB –
Eighteen Sound18NTLW5000
£550.00 · 28% more, worseFs32 Hz +7%
Qts0.32 +60%, worse
Vas176 L +5%
BL31.3 T·m −20%, worse
Xmax17.5 mm +6%
Sensitivity94.5 dB −0.9
REDCATT181XR
£550.48 · 28% more, worseFs30 Hz –
Qts0.23 +15%, worse
Vas195 L +16%, worse
BL28.3 T·m −27%, worse
Xmax17 mm +3%
Sensitivity95.4 dB –
Eighteen Sound18ID200
£723.22 · 68% more, worseFs29 Hz −3%
Qts0.17 −15%, better
Vas136 L −19%, better
BL24.4 T·m −37%, worse
Xmax18 mm +9%
Sensitivity94.7 dB −0.7
B&C19RS115
No current priceFs29 Hz −3%
Qts0.20 –
Vas197 L +17%, worse
BL42 T·m +8%
Xmax23.5 mm +42%, better
Sensitivity95.6 dB –
LavoceSAF185.00
No current priceFs34 Hz +13%, worse
Qts0.23 +15%, worse
Vas164.3 L –
BL37.5 T·m −4%
Xmax11.6 mm −30%, worse
Sensitivity96.3 dB +0.9
B&C18RS115
No current priceFs33 Hz +10%, worse
Qts0.22 +10%
Vas125 L −26%, better
BL40 T·m –
Xmax23.5 mm +42%, better
Sensitivity94.9 dB −0.5
Oberton18XB1500V2
No current priceFs36 Hz +19%, worse
Qts0.23 +12%, worse
Vas192.5 L +15%, worse
BL31.6 T·m −19%, worse
Xmax11 mm −33%, worse
Sensitivity97.9 dB +2.5, better
Eighteen Sound18IDSDS
No current priceFs29 Hz −3%
Qts0.17 −15%, better
Vas136 L −19%, better
BL24.4 T·m −37%, worse
Xmax18 mm +9%
Sensitivity94.7 dB −0.7
VAS Audio18-1700NC
No current priceFs32 Hz +7%
Qts0.28 +40%, worse
Vas178 L +6%
BL34.4 T·m −12%, worse
Xmax13.5 mm −18%, worse
Sensitivity95.1 dB –
Precision DevicesPD.1850/3
No current priceFs33 Hz +10%, worse
Qts0.24 +20%, worse
Vas203.8 L +21%, worse
BL31.0 T·m −21%, worse
Xmax11.1 mm −33%, worse
Sensitivity96.9 dB +1.5
No photo
Precision DevicesPD.1845-1N
No current priceFs34 Hz +14%, worse
Qts0.32 +62%, worse
Vas179.0 L +7%
BL26.4 T·m −32%, worse
Xmax16 mm −3%
Sensitivity95.3 dB –
VAS Audio18-1700FC
No current priceFs33 Hz +10%, worse
Qts0.29 +47%, worse
Vas181 L +8%
BL33 T·m −15%, worse
Xmax13.5 mm −18%, worse
Sensitivity95.4 dB –
Oberton18NXB1600
No current priceFs32 Hz +8%
Qts0.30 +51%, worse
Vas173.1 L +3%
BL29.6 T·m −24%, worse
Xmax13.5 mm −18%, worse
Sensitivity94.5 dB −0.9
Radian Audio2218NEO-8
No current priceFs30 Hz –
Qts0.23 +15%, worse
Vas312 L +86%, worse
BL33 T·m −15%, worse
Xmax9 mm −45%, worse
Sensitivity97.3 dB +1.9
RCFLF18N408
No current priceFs30 Hz –
Qts0.33 +65%, worse
Vas193 L +15%, worse
BL25.7 T·m −34%, worse
Xmax15 mm −9%
Sensitivity93.6 dB −1.8
Tune the match
Choose the published values that matter to your design. Size stays matched to this driver.
Qts
Qes
VasL
Xmaxmm
BLTm
- Thomann5.0 out of 54 ratings · Checked 9 Oct 2026Read reviews on Thomann
- Parts Express5.0 out of 53 ratings · Checked 9 Oct 2026Read reviews on Parts Express
Each shop collects its own ratings. Bits shows them as published and doesn't verify them.
| Shop | Price | Against the lowest | Stock | Link |
|---|---|---|---|---|
JP Leisure | £448.36, the lowest price | In stock | Visit shop at JP Leisure | |
JP Leisure Not currently listed · Last seen 7 Aug 2026 | £448.36 | In stock | Visit shop at JP Leisure | |
JP Leisure Not currently listed · Last seen 7 Aug 2026 | £448.36 | In stock | Visit shop at JP Leisure | |
JP Leisure | £448.36 | In stock | Visit shop at JP Leisure | |
Blue Aran | £448.99 | 0.1% above the lowest price | 8+ in stock | Visit shop at Blue Aran |
Blue Aran | £448.99 | 0.1% above the lowest price | 3 in stock | Visit shop at Blue Aran |
Thomann | £449.00 | 0.1% above the lowest price | In stock | Visit shop at Thomann |
Audio Video Parts Import VAT and duty may apply | £388.32 | Special order | Visit shop at Audio Video Parts | |
Parts Express Import VAT and duty may apply | £570.88 | 27% above the lowest price | 2 in stock | Visit shop at Parts Express |
Best price over time
Tracked since 1 Apr
Recent changes
- 7 OctBlue Aran£454.99 → £448.99Down 1.3% from £454.99
- 4 OctThomann£459.00 → £449.00Down 2.2% from £459.00
- 1 OctThomann£458.00 → £459.00Up 0.2% from £458.00