SEAS Lotus Lotus Reference RM120 4" Midrange
Speaker Drivers · SKU: L0021-04S · Brand SEAS Lotus
฿18,500 (incl. VAT) · In stock
SEAS Lotus Lotus Reference RM120 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 | 110 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 | 72 Hz |
| Qts Total Q at resonance (electrical + mechanical) — guides the sealed vs ported choice | 0.35 |
| Qes Electrical Q at resonance — comes from the magnet motor strength | 0.4 |
| Qms Mechanical Q at resonance — from damping of the surround and spider | 2.95 |
| Vas Equivalent air volume of the suspension compliance — used to size the enclosure | 4 L |
| Sd Effective cone area that actually moves air | 50 cm² |
| Xmax Maximum linear excursion — more travel means louder bass without distortion | 1.7 mm |
| Re DC resistance of the voice coil | 3 Ω |
| Le Voice-coil inductance — affects high-frequency response | 0.25 mH |
| Mms Total moving mass, including the air load | 4.55 g |
| BL Motor force factor (magnetic flux × coil length) — higher means tighter cone control | 4 T·m |
| Weight Driver weight | 1300 g |
SEAS Lotus Lotus Reference RM120 4" Midrange datasheet (PDF)