Dayton AudioPSS555-8
£194.48 · 79% less, betterFs28 Hz −10%, better
Qts0.33 +3%
Vas444 L +98%, worse
BL29.7 T·m –
Xmax11 mm −48%, worse
Sensitivity96.4 dB +1.4
21-inch LF driver · NSW series
Eminence NSW6021-124 1Ω
1 Ω · 25–600 Hz
£916.36
SteadyParts Express · 2 in stock · Ships from United States · All 1 offer
- Fs
- 31Hz
- Xmax
- 21mm
- SPL
- 95dB
- Pe
- –
- BL
- 30.5T·m
- Vd
- 3448cm³
- Qts
- 0.32
- Vas
- 225L
Eminence NSW6021-124 is a 21-inch 1 ohm LF driver. The validated T/S data includes Fs 31 Hz, Qts 0.32, Vas 224.6 L, Xmax 21 mm, sensitivity 95 dB, plus 3448 cm³ Vd and 93 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 £916.36.
The published T/S values agree with each other
Thiele/Small
- Fs
- 31Hz
- Qts
- 0.32
- Qes
- 0.33
- Qms
- 10.4
- Vas
- 224.6L
- Re
- 2Ω
- Le
- 1.20mH
Motor and cone
- BL
- 30.5T·m
- Sd
- 1642cm²
- Mms
- 551g
- Xmax
- 21mm
- Vd †
- 3448cm³
Power and response
- Sensitivity †
- 95dB
- Manufacturer sensitivity
- 95dB
- Impedance
- 1Ω
- Range
- 25–600Hz
- EBP †
- 93 · Sealed or vented
Size and mounting
- Diameter
- 549.9mm
- Cutout
- 503.7mm
- Bolt circle
- 525.0mm
- Depth
- 263.9mm
- Weight
- 21.8kg
Other published values
- Cms
- 0.05mm/N
- Xmech
- 40.4
- Power Program
- 5000
† Calculated by bits from the published values
What this validation status means
Everything else Eminence lists
LF · Primary · 21″
- BL
- 30.5T·m
- Fs
- 31Hz
- Le
- 1.20mH
- Re
- 2Ω
- Sd
- 1642cm²
- Cms
- 0.05mm/N
- Mms
- 551g
- Qes
- 0.33
- Qms
- 10.4
- Qts
- 0.32
- SPL
- 95dB
- Vas
- 224.6L
- Xmax
- 21mm
- Xmech
- 40.4
- Impedance
- 1Ω
- Sensitivity
- 95dB
- Low limit
- 25Hz
- Power Program
- 5000
- Calculated sensitivity †
- 95dB
- High limit
- 600Hz
- Manufacturer sensitivity
- 95dB
- Weight
- 21.8kg
- Diameter
- 549.9mm
- Depth
- 263.9mm
- Cutout
- 503.7mm
- Bolt circle
- 525.0mm
02
Compare
Same-size drivers, compared with the NSW6021-124. Clear differences are green when better and red when worse.
This driverNSW6021-124
Best price
£916.36
Fs
31 Hz
Qts
0.32
Vas
224.6 L
BL
30.5 T·m
Xmax
21 mm
Sensitivity
95 dB
Power
–
SB AudienceNERO-21SW1100D
£343.60 · 63% less, betterFs32 Hz +4%
Qts0.34 +6%
Vas312.6 L +39%, worse
BL30 T·m –
Xmax12.2 mm −42%, worse
Sensitivity96.7 dB +1.7
Eighteen Sound21LW2600
£425.60 · 54% less, betterFs27 Hz −12%, better
Qts0.33 +3%
Vas333 L +48%, worse
BL32.5 T·m +7%
Xmax14.6 mm −30%, worse
Sensitivity94.9 dB –
CelestionTSQ2145
£445.00 · 51% less, betterFs30 Hz –
Qts0.34 +7%
Vas253.8 L +13%, worse
BL33.8 T·m +11%, better
Xmax15 mm −29%, worse
Sensitivity94.8 dB –
RCFLF21X451
£448.61 · 51% less, betterFs28 Hz −9%
Qts0.37 +16%, worse
Vas385 L +71%, worse
BL30.5 T·m –
Xmax14 mm −33%, worse
Sensitivity95.4 dB –
Dayton AudioHTS545HE-4
£448.82 · 51% less, betterFs26 Hz −14%, better
Qts0.28 −12%, better
Vas179 L −20%, better
BL38.2 T·m +25%, better
Xmax21 mm –
Sensitivity92.5 dB −2.5, worse
Eighteen Sound21NLW4100
£456.79 · 50% less, betterFs36 Hz +17%, worse
Qts0.46 +44%, worse
Vas210 L −6%
BL29.4 T·m −4%
Xmax15.2 mm −28%, worse
Sensitivity95 dB –
Beyma21LEX1600ND
£475.00 · 48% less, betterFs30 Hz –
Qts0.29 −9%
Vas305 L +36%, worse
BL36.6 T·m +20%, better
Xmax14 mm −33%, worse
Sensitivity96.4 dB +1.4
B&C21DS115
£475.59 · 48% less, betterFs34 Hz +11%, worse
Qts0.27 −16%, better
Vas204 L −9%
BL39.3 T·m +29%, better
Xmax16.5 mm −21%, worse
Sensitivity96.6 dB +1.6
B&C21SW115
£476.43 · 48% less, betterFs33 Hz +8%
Qts0.36 +12%, worse
Vas278 L +24%, worse
BL24.8 T·m −19%, worse
Xmax14 mm −33%, worse
Sensitivity96.3 dB +1.3
Beyma21QLEX1600FE
£493.97 · 46% less, betterFs30 Hz –
Qts0.28 −12%, better
Vas309 L +38%, worse
BL36.4 T·m +19%, better
Xmax13 mm −38%, worse
Sensitivity96.5 dB +1.5
Eighteen Sound21NLW9001
£549.89 · 40% less, betterFs32 Hz +4%
Qts0.31 −3%
Vas244 L +9%
BL37 T·m +21%, better
Xmax14 mm −33%, worse
Sensitivity95.7 dB +0.7
No photo
Precision DevicesPD.2155-1N
£555.00 · 39% less, betterFs33 Hz +8%
Qts0.36 +12%, worse
Vas241 L +7%
BL30 T·m –
Xmax14 mm −33%, worse
Sensitivity95.7 dB +0.7
B&C21SW152
£585.00 · 36% less, betterFs32 Hz +4%
Qts0.30 −6%
Vas200 L −11%, better
BL32.5 T·m +7%
Xmax15 mm −29%, worse
Sensitivity95.3 dB –
Eighteen Sound21NLW9601
£593.90 · 35% less, betterFs41 Hz +34%, worse
Qts0.32 –
Vas123 L −45%, better
BL32.7 T·m +7%
Xmax14 mm −33%, worse
Sensitivity96.1 dB +1.1
Eighteen Sound21NTLW5000
£595.00 · 35% less, betterFs30 Hz –
Qts0.32 –
Vas300 L +34%, worse
BL25 T·m −18%, worse
Xmax17.5 mm −17%, worse
Sensitivity95.9 dB +0.9
Eighteen Sound21NLW4000
£608.33 · 34% less, betterFs29 Hz −5%
Qts0.37 +16%, worse
Vas305 L +36%, worse
BL30 T·m –
Xmax15 mm −29%, worse
Sensitivity94.9 dB –
No photo
Precision DevicesPD.2160-1N
£799.00 · 13% less, betterFs35 Hz +14%, worse
Qts0.30 −6%
Vas177 L −21%, better
BL43 T·m +41%, better
Xmax16 mm −24%, worse
Sensitivity95.9 dB +0.9
FaitalPRO21XL3000
£878.34 · 4% lessFs32 Hz +4%
Qts0.22 −31%, better
Vas223.5 L –
BL35.5 T·m +16%, better
Xmax17.7 mm −16%, worse
Sensitivity97.3 dB +2.3, better
Dayton AudioPSS545HE-4
No current priceFs29 Hz −6%
Qts0.27 −16%, better
Vas212.2 L −6%
BL35.5 T·m +16%, better
Xmax21 mm –
Sensitivity94.6 dB –
CelestionNTR21-5010JD
No current priceFs32 Hz +5%
Qts0.32 –
Vas276.7 L +23%, worse
BL33.9 T·m +11%, better
Xmax9 mm −57%, worse
Sensitivity96.4 dB +1.4
Eighteen Sound21NLW5300
No current priceFs31 Hz –
Qts0.32 –
Vas325 L +45%, worse
BL31 T·m –
Xmax15.3 mm −27%, worse
Sensitivity96.6 dB +1.6
No current price
Fs35 Hz +14%, worse
Qts0.34 +6%
Vas266 L +18%, worse
BL31.3 T·m –
Xmax14 mm −33%, worse
Sensitivity97.1 dB +2.1, better
No photo
Precision DevicesPD.2155-1F
No current priceFs35 Hz +14%, worse
Qts0.34 +6%
Vas266 L +18%, worse
BL31.3 T·m –
Xmax14 mm −33%, worse
Sensitivity97.1 dB +2.1, better
No current price
Fs33 Hz +8%
Qts0.36 +12%, worse
Vas241 L +7%
BL30 T·m –
Xmax14 mm −33%, worse
Sensitivity95.7 dB +0.7
Sica21 S 4 PL
No current priceFs35 Hz +13%, worse
Qts0.30 −6%
Vas255 L +14%, worse
BL36.1 T·m +18%, better
Xmax5.2 mm −75%, worse
Sensitivity97.4 dB +2.4, better
Eighteen Sound21NLW9601C
No current priceFs38 Hz +24%, worse
Qts0.29 −9%
Vas140 L −38%, better
BL33.2 T·m +9%
Xmax14 mm −33%, worse
Sensitivity96 dB +1
B&C21SW150
No current priceFs29 Hz −5%
Qts0.26 −19%, better
Vas254 L +13%, worse
BL32.6 T·m +7%
Xmax15 mm −29%, worse
Sensitivity95.6 dB +0.6
Eighteen Sound21LW2500
No current priceFs29 Hz −5%
Qts0.37 +16%, worse
Vas305 L +36%, worse
BL30 T·m –
Xmax14 mm −33%, worse
Sensitivity94.9 dB –
P.AudioSD21-125XB
No current priceFs35 Hz +14%, worse
Qts0.38 +19%, worse
Vas345.6 L +54%, worse
BL30.4 T·m –
Xmax11.3 mm −46%, worse
Sensitivity97.7 dB +2.7, better
Tune the match
Choose the published values that matter to your design. Size stays matched to this driver.
Qts
Qes
VasL
Xmaxmm
BLTm
- Parts Express5.0 out of 52 ratings · Checked 25 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 |
|---|---|---|---|---|
Parts Express Import VAT and duty may apply | £916.36, the lowest price | 2 in stock | Visit shop at Parts Express |
Best price over time
Tracked since 22 Jul