REDCATT61FHM-2
£20.16 · 87% less, betterFs44 Hz −84%, better
Qts0.52 −13%, better
Vas14.4 L +1957%, worse
BL6.0 T·m −57%, worse
Xmax3.2 mm +14%, better
Sensitivity85.3 dB −10.3, worse
6.5-inch LF driver · 6NSM series · 51 mm voice coil · 250 W
B&C 6NSM51 8Ω
8 Ω · 300–6000 Hz
£150.97
SteadyJP Leisure · In stock · All 3 offers
- Fs
- 280Hz
- Xmax
- 2.8mm
- SPL
- 96dB
- Pe
- 250W
- BL
- 13.9T·m
- Vd
- 40cm³
- Qts
- 0.60
- Vas
- 0.7L
Published graphs
B&C 6NSM51 is a 6.5-inch 8 ohm LF driver rated at 250 W RMS. The validated T/S data includes Fs 280 Hz, Qts 0.60, Vas 0.7 L, Xmax 2.8 mm, sensitivity 95.6 dB, plus 40 cm³ Vd and 412 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 £150.80.
The published T/S values agree with each other
Thiele/Small
- Fs
- 280Hz
- Qts
- 0.60
- Qes
- 0.68
- Qms
- 5.4
- Vas
- 0.7L
- Re
- 5.4Ω
- Le
- 0.15mH
Motor and cone
- BL
- 13.9T·m
- Sd
- 143cm²
- Mms
- 14g
- Xmax
- 2.8mm
- Vd †
- 40cm³
- Voice coil
- 51mm
- Flux density
- 1.60T
Power and response
- Sensitivity †
- 95.6dB
- Manufacturer sensitivity
- 100dB
- Power
- 250W
- Nominal power
- 250W
- Impedance
- 8Ω
- Min. impedance
- 6.6Ω
- Range
- 300–6000Hz
- EBP †
- 412 · Leans vented
Size and mounting
- Diameter
- 187mm
- Cutout
- 151mm
- Bolt circle
- 172mm
- Depth
- 113mm
- Weight
- 2.3kg
Sensitivity shows 95.6 dB, calculated from the T/S values. B&C publishes 100.0 dB, 4.4 dB apart.
† Calculated by bits from the published values
What this validation status means
Everything else B&C lists
LF
- BL
- 13.9T·m
- Fs
- 280Hz
- Le
- 0.15mH
- Re
- 5.4Ω
- Sd
- 143cm²
- Mms
- 14g
- Qes
- 0.68
- Qms
- 5.4
- Qts
- 0.60
- SPL
- 95.6dB
- Vas
- 0.7L
- Xmax
- 2.8mm
- Power
- 250W
- Impedance
- 8Ω
- Flux density
- 1.60T
- Sensitivity
- 100dB
- Low limit
- 300Hz
- Nominal power
- 250W
- Calculated sensitivity †
- 95.6dB
- High limit
- 6000Hz
- Manufacturer sensitivity
- 100dB
- Min. impedance
- 6.6Ω
- Voice coil
- 51mm
- Weight
- 2.3kg
- Diameter
- 187mm
- Depth
- 113mm
- Cutout
- 151mm
- Bolt circle
- 172mm
- Bl
- 13.9 Tm
- Fs
- 280 Hz
- Le
- 0.15 mH
- Re
- 5.4 Ω
- Sd
- 143 cm² (22.17 in²)
- Ebp
- 412 Hz
- Mms
- 13.5 g
- Qes
- 0.68
- Qms
- 5.4
- Qts
- 0.6
- Vas
- 0.7 dm³ (0.02 ft³)
- Η0
- 2.2 %
- Cone
- RCK06NSM518
- Xmax
- 2.8 mm
- Xvar
- 3 mm
- Depth
- 113 mm (4.45 in)
- Spider
- Single
- Cone shape
- Radial
- Net weight
- 2.25 kg (4.96 lb)
- Pole design
- T-Pole
- Sensitivity
- 100 dB
- Flux density
- 1.6 T
- Shipping box
- 210x180x150 mm (8.27x7.09x5.91 in)
- Winding depth
- 8.5 mm (0.33 in)
- Shipping units
- 1 pcs
- Surround shape
- Triple Roll
- Former material
- Glass Fibre
- Frequency range
- 300 Hz - 6000 Hz
- Magnet material
- Neodymium Ring
- Shipping weight
- 2.48 kg (5.46 lb)
- Nominal diameter
- 170 mm (6.5 in)
- Overall diameter
- 187 mm (7.36 in)
- Winding material
- Aluminium
- Minimum impedance
- 6.6 Ω
- Nominal impedance
- 8 Ω
- Magnetic gap depth
- 6 mm (0.24 in)
- Voice coil diameter
- 51 mm (2 in)
- Bolt circle diameter
- 172 mm (6.77 in)
- Woofer cone treatment
- WP Waterproof Front Side
- Baffle cutout diameter
- 151 mm (5.94 in)
- Nominal power handling
- 250 W
- Continuous power handling
- 500 W
- Flange and gasket thickness
- 11 mm (0.43 in)
- Air volume occupied by driver
- 2 dm³ (0.07 ft³)
02
Compare
Same-size drivers, compared with the 6NSM51. Clear differences are green when better and red when worse.
This driver6NSM51
Best price
£150.80
Fs
280 Hz
Qts
0.60
Vas
0.7 L
BL
13.9 T·m
Xmax
2.8 mm
Sensitivity
95.6 dB
Power
250 W
MonacorSPM-165/8
£27.96 · 81% less, betterFs49 Hz −83%, better
Qts0.55 −8%
Vas33 L +4614%, worse
BL5.8 T·m −58%, worse
Xmax3 mm +7%
Sensitivity89.7 dB −5.9, worse
REDCATT61FIND
£29.65 · 80% less, betterFs130 Hz −54%, better
Qts0.62 +3%
Vas2.6 L +277%, worse
BL15.6 T·m +13%, better
Xmax2.3 mm −18%, worse
Sensitivity91.2 dB −4.4, worse
MonacorSPH-174KE
£29.65 · 80% less, betterFs42 Hz −85%, better
Qts0.51 −15%, better
Vas26 L +3614%, worse
BL5.9 T·m −57%, worse
Xmax3 mm +7%
Sensitivity86.8 dB −8.8, worse
Dayton AudioDA175-8
£30.23 · 80% less, betterFs39 Hz −86%, better
Qts0.58 −3%
Vas16.3 L +2229%, worse
BL7.2 T·m −48%, worse
Xmax4.3 mm +52%, better
Sensitivity83.4 dB −12.2, worse
Dayton AudioMB620-8
£34.01 · 77% less, betterFs104 Hz −63%, better
Qts0.59 –
Vas6.8 L +867%, worse
BL6.7 T·m −52%, worse
Xmax2 mm −29%, worse
Sensitivity92.5 dB −3.1, worse
FaneSOVEREIGN 6-100
£42.00 · 72% less, betterFs115 Hz −59%, better
Qts0.64 +7%
Vas2.2 L +214%, worse
BL13.3 T·m −5%
Xmax2.5 mm −11%, worse
Sensitivity89 dB −6.6, worse
CelestionTF0615
£47.00 · 69% less, betterFs105 Hz −63%, better
Qts0.61 –
Vas6.4 L +816%, worse
BL8.8 T·m −36%, worse
Xmax1.8 mm −37%, worse
Sensitivity92.1 dB −3.5, worse
PRV Audio6MR400-4
£49.09 · 67% less, betterFs144 Hz −49%, better
Qts0.60 –
Vas4.4 L +529%, worse
BL6.4 T·m −54%, worse
Xmax3.3 mm +16%, better
Sensitivity95.2 dB –
WavecorWF146WA02
£58.22 · 61% less, betterFs58 Hz −79%, better
Qts0.51 −15%, better
Vas10 L +1329%, worse
BL6.4 T·m −54%, worse
Xmax3 mm +7%
Sensitivity87.6 dB −8, worse
WavecorWF168WA02
£61.25 · 59% less, betterFs49 Hz −83%, better
Qts0.52 −13%, better
Vas24.6 L +3414%, worse
BL6.4 T·m −54%, worse
Xmax3 mm +7%
Sensitivity89.2 dB −6.4, worse
FaitalPRO6PR110
£62.80 · 58% less, betterFs100 Hz −64%, better
Qts0.53 −12%, better
Vas5.6 L +700%, worse
BL8.5 T·m −39%, worse
Xmax2.8 mm –
Sensitivity91.7 dB −3.9, worse
EminenceBETA-6A
£64.09 · 57% less, betterFs123 Hz −56%, better
Qts0.56 −7%
Vas3.5 L +401%, worse
BL8.1 T·m −42%, worse
Xmax4.5 mm +61%, better
Sensitivity92 dB −3.6, worse
Beyma6MI100
£67.06 · 56% less, betterFs128 Hz −54%, better
Qts0.51 −15%, better
Vas3.1 L +343%, worse
BL10.8 T·m −22%, worse
Xmax3 mm +7%
Sensitivity92.8 dB −2.8, worse
SB AudienceNERO-6MRN150D
£169.39 · 12% more, worseFs200 Hz −29%, better
Qts0.48 −20%, better
Vas1.1 L +57%, worse
BL13.1 T·m −6%
Xmax3.4 mm +23%, better
Sensitivity93.8 dB −1.8
Scanspeak18M/4631T00
£194.81 · 29% more, worseFs65 Hz −77%, better
Qts0.60 –
Vas14 L +1900%, worse
BL5.6 T·m −60%, worse
Xmax3 mm +7%
Sensitivity89.6 dB −6, worse
Supravox165-2000 MK2
£199.67 · 32% more, worseFs77 Hz −73%, better
Qts0.70 +17%, worse
Vas25.8 L +3586%, worse
BL3.5 T·m −75%, worse
Xmax2.9 mm +4%
Sensitivity93.7 dB −1.9
Beyma6MCF200ND
£300.43 · 99% more, worseFs406 Hz +45%, worse
Qts0.72 +20%, worse
Vas0.27 L −61%, better
BL18.1 T·m +30%, better
Xmax2.5 mm −11%, worse
Sensitivity95.7 dB –
LavoceMAN061.80
No current priceFs172 Hz −39%, better
Qts0.57 −5%
Vas1.6 L +127%, worse
BL11.0 T·m −21%, worse
Xmax3 mm +7%
Sensitivity93 dB −2.6, worse
Dayton AudioE150MR-8
No current priceFs74 Hz −74%, better
Qts0.58 −3%
Vas8 L +1043%, worse
BL6.1 T·m −56%, worse
Xmax2.7 mm −4%
Sensitivity88.9 dB −6.7, worse
SB AudienceNERO-6MRN151D
No current priceFs230 Hz −18%, better
Qts0.48 −20%, better
Vas0.8 L +14%, worse
BL14.5 T·m +4%
Xmax4 mm +43%, better
Sensitivity94.3 dB −1.3
Dayton AudioE150MR-4
No current priceFs75 Hz −73%, better
Qts0.52 −13%, better
Vas7.4 L +957%, worse
BL4.9 T·m −65%, worse
Xmax2.7 mm −4%
Sensitivity89.1 dB −6.5, worse
CelestionCN0617M
No current priceFs198 Hz −29%, better
Qts0.50 −16%, better
Vas2.0 L +190%, worse
BL17.6 T·m +27%, better
Xmax2.7 mm −4%
Sensitivity96.6 dB +1
No photo
PHL Audio1660NDM-SQ2
No current priceFs360 Hz +29%, worse
Qts0.90 +50%, worse
Vas0.5 L −29%, better
BL12.5 T·m −10%, worse
Xmax2.5 mm −11%, worse
Sensitivity95.8 dB –
PRV Audio6MB400
No current priceFs117 Hz −58%, better
Qts0.60 –
Vas5.7 L +713%, worse
BL8.3 T·m −41%, worse
Xmax4 mm +43%, better
Sensitivity93.6 dB −2, worse
PeerlessSDS-160F25PR01-08
No current priceFs48 Hz −83%, better
Qts0.58 −3%
Vas21.8 L +3014%, worse
BL6.6 T·m −52%, worse
Xmax8.1 mm +188%, better
Sensitivity87.5 dB −8.1, worse
MonacorTF0615/8
No current priceFs105 Hz −63%, better
Qts0.61 –
Vas6.4 L +814%, worse
BL8.8 T·m −36%, worse
Xmax1.8 mm −37%, worse
Sensitivity92.1 dB −3.5, worse
PRV Audio6MB400-4
No current priceFs125 Hz −55%, better
Qts0.52 −13%, better
Vas5.3 L +657%, worse
BL6.6 T·m −53%, worse
Xmax3 mm +7%
Sensitivity94.7 dB −0.9
No photo
LavoceCSF061.21
No current priceFs90 Hz −68%, better
Qts0.67 +12%, worse
Vas8.5 L +1111%, worse
BL6.1 T·m −56%, worse
Xmax3.2 mm +14%, better
Sensitivity91 dB −4.6, worse
No photo
PHL Audio1120
No current priceFs135 Hz −52%, better
Qts0.56 −7%
Vas4.4 L +529%, worse
BL8.5 T·m −39%, worse
Xmax2 mm −29%, worse
Sensitivity94.4 dB −1.2
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 |
|---|---|---|---|---|
JP Leisure | £150.97, the lowest price | In stock | Visit shop at JP Leisure | |
JP Leisure Not currently listed · Last seen 7 Aug 2026 | £150.97 | In stock | Visit shop at JP Leisure |
Best price over time
Tracked since 1 Apr
Recent changes
- 23 JunJP Leisure£144.19 → £150.97Up 4.7% from £144.19