SB Acoustics NRX SB12MNRX2-25-4 4" Midrange

Speaker Drivers · SKU: SB12MNRX2-25-4 · Brand SB Acoustics

฿3,200 (incl. VAT) · Pre-order

SB Acoustics NRX SB12MNRX2-25-4 4" Midrange

SB Acoustics NRX SB12MNRX2-25-4 4" Midrange specifications

Diameter
Cone diameter — larger cones move more air and reach deeper bass
4"
Impedance
Voice-coil electrical resistance — must match your amplifier (e.g. 4Ω/8Ω)
4 Ω
Power (RMS)
Continuous power the driver handles safely (RMS) — not peak power
50 W
Sensitivity (SPL)
Sensitivity — loudness at 1W/1m; higher means louder with less amplifier power
90.5 dB
Fs
Free-air resonance frequency — lower generally means deeper bass extension
63.5 Hz
Qts
Total Q at resonance (electrical + mechanical) — guides the sealed vs ported choice
0.32
Qes
Electrical Q at resonance — comes from the magnet motor strength
0.35
Qms
Mechanical Q at resonance — from damping of the surround and spider
4.19
Vas
Equivalent air volume of the suspension compliance — used to size the enclosure
5.3 L
Sd
Effective cone area that actually moves air
50 cm²
Xmax
Maximum linear excursion — more travel means louder bass without distortion
2.2 mm
Re
DC resistance of the voice coil
3.2 Ω
Le
Voice-coil inductance — affects high-frequency response
0.15 mH
Mms
Total moving mass, including the air load
4.2 g
BL
Motor force factor (magnetic flux × coil length) — higher means tighter cone control
3.9 T·m
Weight
Driver weight
920 g

SB Acoustics NRX SB12MNRX2-25-4 4" Midrange datasheet (PDF)

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