B&C design · archived
S21AN
21" 3400W Subwoofer Enclosure - 21" Neo Subwoofer
- Drivers
- 21SW115, 8 Ω
- Power
- 3,400 W
Designed with the 8 Ω version.
21-inch LF driver · 21SW series · 116 mm voice coil · 1,700 W
B&C 21SW115 4Ω
33–1000 Hz
£481.99
SteadyBlue Aran · 2 in stock · All 7 offers
- Fs
- 33Hz
- Xmax
- 14mm
- SPL
- 96dB
- Pe
- 1700W
- BL
- 24.8T·m
- Vd
- 2352cm³
- Qts
- 0.36
- Vas
- 278L
Published graphs
B&C 21SW115 is a 21-inch 4 ohm LF driver rated at 1700 W RMS. The validated T/S data includes Fs 33 Hz, Qts 0.36, Vas 278 L, Xmax 14 mm, sensitivity 96.3 dB, plus 2352 cm³ Vd and 89 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 £481.92.
The published T/S values agree with each other
Thiele/Small
- Fs
- 33Hz
- Qts
- 0.36
- Qes
- 0.37
- Qms
- 7.7
- Vas
- 278L
- Re
- 3.6Ω
- Le
- 1.70mH
Motor and cone
- BL
- 24.8T·m
- Sd
- 1680cm²
- Mms
- 335g
- Xmax
- 14mm
- Vd †
- 2352cm³
- Voice coil
- 116mm
- Flux density
- 1.15T
Power and response
- Sensitivity †
- 96.3dB
- Manufacturer sensitivity
- 97dB
- Power
- 1700W
- Nominal power
- 1700W
- Impedance
- 4Ω
- Min. impedance
- 4.2Ω
- Range
- 33–1000Hz
- EBP †
- 89 · Sealed or vented
Size and mounting
- Diameter
- 547mm
- Cutout
- 503mm
- Bolt circle
- 527mm
- Depth
- 249mm
- Weight
- 14kg
† Calculated by bits from the published values
What this validation status means
Everything else B&C lists
LF
- BL
- 24.8T·m
- Fs
- 33Hz
- Le
- 1.70mH
- Re
- 3.6Ω
- Sd
- 1680cm²
- Mms
- 335g
- Qes
- 0.37
- Qms
- 7.7
- Qts
- 0.36
- SPL
- 96.3dB
- Vas
- 278L
- Xmax
- 14mm
- Power
- 1700W
- Impedance
- 4Ω
- Flux density
- 1.15T
- Sensitivity
- 97dB
- Low limit
- 33Hz
- Nominal power
- 1700W
- Calculated sensitivity †
- 96.3dB
- High limit
- 1000Hz
- Manufacturer sensitivity
- 97dB
- Min. impedance
- 4.2Ω
- Voice coil
- 116mm
- Weight
- 14kg
- Diameter
- 547mm
- Depth
- 249mm
- Cutout
- 503mm
- Bolt circle
- 527mm
- Bl
- 24.8 Tm
- Fs
- 33 Hz
- Le
- 1.7 mH
- Re
- 3.6 Ω
- Sd
- 1680 cm² (260.4 in²)
- Ebp
- 89 Hz
- Mms
- 335 g
- Qes
- 0.37
- Qms
- 7.7
- Qts
- 0.36
- Vas
- 278 dm³ (9.7 ft³)
- Η0
- 2.6 %
- Cone
- RCK21SW1154
- Xmax
- 14 mm
- Xvar
- 15 mm
- Depth
- 249 mm (9.8 in)
- Spider
- Double Silicone
- Cone shape
- Radial
- Net weight
- 14 kg (30.8 lb)
- Pole design
- T-Pole
- Sensitivity
- 97 dB
- Flux density
- 1.15 T
- Shipping box
- 570x570x320 mm (22.44x22.44x12.60 in)
- Winding depth
- 34 mm (1.34 in)
- Shipping units
- 1 pcs
- Surround shape
- Triple Roll
- Former material
- Glass Fibre
- Frequency range
- 33 Hz - 1000 Hz
- Magnet material
- Neodymium Inside Slug
- Shipping weight
- 16.3 kg (35.94 lb)
- Nominal diameter
- 530 mm (21 in)
- Overall diameter
- 547 mm (21.5 in)
- Winding material
- Copper
- Minimum impedance
- 4.2 Ω
- Nominal impedance
- 4 Ω
- Magnetic gap depth
- 14 mm (0.55 in)
- Recommended tuning
- 32 Hz
- Voice coil diameter
- 116 mm (4.5 in)
- Bolt circle diameter
- 527 mm (20.7 in)
- Recommended enclosure
- 250 dm³ (8.83 ft³)
- Woofer cone treatment
- TWP Waterproof Both Sides
- Baffle cutout diameter
- 503 mm (19.8 in)
- Nominal power handling
- 1700 W
- Continuous power handling
- 3400 W
- Flange and gasket thickness
- 14 mm (0.53 in)
- Air volume occupied by driver
- 15 dm³ (0.53 ft³)
02
Designs
Cabinets for the 21SW115: a design and a suggested box from B&C.
All 21SW115 designsHow we find designsB&C’s design
From the maker, with plans to download
B&C’s suggested box
From B&C’s 21SW115 page
- Net volume
- 250L
- Tuning
- 32Hz
B&C gives the volume and tuning; the port is sized for the driver when you open it.
Modelling the box in 00 Simulator…
03
Compare
Same-size drivers, compared with the 21SW115. Clear differences are green when better and red when worse.
This driver21SW115
Best price
£481.92
Fs
33 Hz
Qts
0.36
Vas
278 L
BL
24.8 T·m
Xmax
14 mm
Sensitivity
96.3 dB
Power
1700 W
Dayton AudioPSS555-8
£196.85 · 59% less, betterFs28 Hz −16%, better
Qts0.33 −8%
Vas444 L +60%, worse
BL29.7 T·m +20%, better
Xmax11 mm −21%, worse
Sensitivity96.4 dB –
SB AudienceNERO-21SW1100D
£343.60 · 29% less, betterFs32 Hz −3%
Qts0.34 −6%
Vas312.6 L +12%, worse
BL30 T·m +21%, better
Xmax12.2 mm −13%, worse
Sensitivity96.7 dB –
SB AudienceROSSO-21SW800
£423.44 · 12% less, betterFs38 Hz +15%, worse
Qts0.76 +111%, worse
Vas224.4 L −19%, better
BL24.1 T·m –
Xmax11.4 mm −18%, worse
Sensitivity93.9 dB −2.4, worse
Beyma21QLEX1600FE
£425.00 · 12% less, betterFs30 Hz −9%
Qts0.28 −22%, better
Vas309 L +11%, worse
BL36.4 T·m +47%, better
Xmax13 mm −7%
Sensitivity96.5 dB –
CelestionTSQ2145
£445.00 · 8% less, betterFs30 Hz −9%
Qts0.34 −4%
Vas253.8 L −9%
BL33.8 T·m +36%, better
Xmax15 mm +7%
Sensitivity94.8 dB −1.5
Beyma21LEX1600ND
£475.00 · 1% lessFs30 Hz −9%
Qts0.29 −19%, better
Vas305 L +10%
BL36.6 T·m +48%, better
Xmax14 mm –
Sensitivity96.4 dB –
LavoceSAN214.50
£481.92 · Same priceFs33 Hz –
Qts0.28 −22%, better
Vas218.3 L −21%, better
BL39.6 T·m +60%, better
Xmax15.4 mm +10%, better
Sensitivity96.4 dB –
B&C21DS115
£490.39 · 2% moreFs32 Hz −3%
Qts0.21 −42%, better
Vas219 L −21%, better
BL28.6 T·m +15%, better
Xmax15 mm +7%
Sensitivity97.2 dB +0.9
Eighteen Sound21NLW4100
£512.25 · 6% more, worseFs34 Hz +3%
Qts0.40 +11%, worse
Vas219 L −21%, better
BL22.8 T·m −8%
Xmax15.2 mm +9%
Sensitivity95.1 dB −1.2
B&C21SW152
£585.00 · 21% more, worseFs32 Hz −3%
Qts0.30 −17%, better
Vas200 L −28%, better
BL32.5 T·m +31%, better
Xmax15 mm +7%
Sensitivity95.3 dB −1
Eighteen Sound21NLW9001
£594.65 · 23% more, worseFs31 Hz −6%
Qts0.34 −6%
Vas272 L –
BL23.8 T·m −4%
Xmax14 mm –
Sensitivity95.4 dB −0.9
Eighteen Sound21NTLW5000
£595.00 · 23% more, worseFs30 Hz −9%
Qts0.32 −11%, better
Vas300 L +8%
BL25 T·m –
Xmax17.5 mm +25%, better
Sensitivity95.9 dB –
Eighteen Sound21NLW9601
£600.74 · 25% more, worseFs41 Hz +24%, worse
Qts0.32 −11%, better
Vas123 L −56%, better
BL32.7 T·m +32%, better
Xmax14 mm –
Sensitivity96.1 dB –
EminenceNSW6021-6
£800.00 · 66% more, worseFs29 Hz −12%, better
Qts0.31 −14%, better
Vas224.6 L −19%, better
BL33.8 T·m +36%, better
Xmax21 mm +50%, better
Sensitivity94.5 dB −1.8
No photo
Precision DevicesPD.2160-1N
£811.00 · 68% more, worseFs35 Hz +6%
Qts0.30 −17%, better
Vas177 L −36%, better
BL43 T·m +73%, better
Xmax16 mm +14%, better
Sensitivity95.9 dB –
EminenceNSW6021-124
£927.53 · 92% more, worseFs31 Hz −7%
Qts0.32 −11%, better
Vas224.6 L −19%, better
BL30.5 T·m +23%, better
Xmax21 mm +50%, better
Sensitivity95 dB −1.3
No current price
Fs33 Hz –
Qts0.36 –
Vas241 L −13%, better
BL30 T·m +21%, better
Xmax14 mm –
Sensitivity95.7 dB −0.6
No photo
Precision DevicesPD.2155-1N
No current priceFs33 Hz –
Qts0.36 –
Vas241 L −13%, better
BL30 T·m +21%, better
Xmax14 mm –
Sensitivity95.7 dB −0.6
No current price
Fs35 Hz +6%
Qts0.34 −6%
Vas266 L −4%
BL31.3 T·m +26%, better
Xmax14 mm –
Sensitivity97.1 dB +0.8
No photo
Precision DevicesPD.2155-1F
No current priceFs35 Hz +6%
Qts0.34 −6%
Vas266 L −4%
BL31.3 T·m +26%, better
Xmax14 mm –
Sensitivity97.1 dB +0.8
RCFLF21X451
No current priceFs28 Hz −15%, better
Qts0.37 –
Vas385 L +38%, worse
BL30.5 T·m +23%, better
Xmax14 mm –
Sensitivity95.4 dB −0.9
Eighteen Sound21LW2600
No current priceFs27 Hz −18%, better
Qts0.29 −19%, better
Vas332 L +19%, worse
BL24.9 T·m –
Xmax14.6 mm +4%
Sensitivity95.6 dB −0.7
Eighteen Sound21NLW5300
No current priceFs31 Hz −6%
Qts0.32 −11%, better
Vas325 L +17%, worse
BL31 T·m +25%, better
Xmax15.3 mm +9%
Sensitivity96.6 dB –
P.AudioSD21-125XB
No current priceFs35 Hz +6%
Qts0.38 +6%
Vas345.6 L +24%, worse
BL30.4 T·m +23%, better
Xmax11.3 mm −20%, worse
Sensitivity97.7 dB +1.4
BishopSoundBWN21/4
No current priceFs29 Hz −12%, better
Qts0.42 +16%, worse
Vas244.2 L −12%, better
BL32.6 T·m +31%, better
Xmax15 mm +7%
Sensitivity93.2 dB −3.1, worse
BishopSoundBWN21/8
No current priceFs29 Hz −12%, better
Qts0.42 +16%, worse
Vas244.2 L −12%, better
BL32.6 T·m +31%, better
Xmax15 mm +7%
Sensitivity93.2 dB −3.1, worse
CelestionNTR21-5010JD
No current priceFs32 Hz –
Qts0.32 −11%, better
Vas276.7 L –
BL33.9 T·m +36%, better
Xmax9 mm −36%, worse
Sensitivity96.4 dB –
Eighteen Sound21ID
No current priceFs38 Hz +15%, worse
Qts0.23 −36%, better
Vas143 L −49%, better
BL25.2 T·m –
Xmax14 mm –
Sensitivity97.2 dB +0.9
Eighteen Sound21NLW9601C
No current priceFs38 Hz +15%, worse
Qts0.29 −19%, better
Vas140 L −50%, better
BL33.2 T·m +34%, better
Xmax14 mm –
Sensitivity96 dB –
Sica21 S 4 PL
No current priceFs35 Hz +5%
Qts0.30 −17%, better
Vas255 L −8%
BL36.1 T·m +46%, better
Xmax5.2 mm −63%, worse
Sensitivity97.4 dB +1.1
Tune the match
Choose the published values that matter to your design. Size stays matched to this driver.
Qts
Qes
VasL
Xmaxmm
BLTm
| Shop | Price | Against the lowest | Stock | Link |
|---|---|---|---|---|
Blue Aran | £481.99, the lowest price | 2 in stock | Visit shop at Blue Aran | |
JP Leisure Not currently listed · Last seen 7 Aug 2026 | £491.16 | 1.9% above the lowest price | In stock | Visit shop at JP Leisure |
JP Leisure | £491.16 | 1.9% above the lowest price | In stock | Visit shop at JP Leisure |
Audio Video Parts Import VAT and duty may apply | £418.98 | Special order | Visit shop at Audio Video Parts |
Best price over time
Tracked since 1 Apr
Recent changes
- 17 JulBlue Aran£489.00 → £481.99Down 1.4% from £489.00
- 23 JunJP Leisure£499.52 → £491.16Down 1.7% from £499.52
- 5 JunBlue Aran£435.00 → £489.00Up 12% from £435.00