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https://www.aliexpress.com/i/1005005432680072.html
Description Size: 3 inch Impedance: 4Ω/ 8Ω Rated power: 20W/30w Package include: 2pcs speaker
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https://www.aliexpress.com/item/1005005820259984.html Speaker type: subwoofer Rated power: 35W Maximum power: 60W Rated impedance: 4 Ω / 8 Ω Frequency response range: 85HZ-5KHZ Resonance frequency: 85HZ Sensitivity: 87db±3db Basin material: Polymer pp Maximum outer diameter: 89.5 mm Speaker height: 51 mm Screw diagonal distance: 83 mm Voice coil diameter: 25 mm Qts :0.43
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https://www.aliexpress.com/item/1005002028341057.html
4 inch subwoofer HiFi glass fiber cone speaker Rated power: 40W Maximum power: 80W Impedance: 4 Ohm, 8 Ohm Frequency: 69-2KHz Sensitivity: 88db±3db Equivalent volume: 8L Qts: 0.49 Fo: 69Hz Voice coil: 25mm Net weight: 1.05kg
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TS Parameters file Room EQ V5.20.13 Dated: Jul 23, 2023 11:23:25 PM From measurement sub Jul 23
Zmin 3.58 ohm fmin 249 Hz f3 633 Hz Le(f3) 0.717 mH Motional impedance parameters R0 18.47 ohm CMES 457.3 uF L0 9.663 mH beta 0.0002 omega0 705.6 Blocked impedance parameters RDC 3.50 ohm dR -0.39 ohm Re 3.11 ohm Leb 0.0 uH Le 1.319 mH Rss 627.9 ohm Ke 0.1450 S-H Thiele-Small parameters fs 75.7 Hz Qms 4.014 Qes 0.676 Qts 0.578 Fts 130.9 Mms 11.48 g Cms 0.385 mm/N Rms 1.360 kg/s Vas 1.52 litres Bl 5.010 Tm Eta 0.09 % Lp (1W/1m) 81.78 dB Dd 8.20 cm Sd 52.8 cm^2 Added mass 1 measurement: Added mass 1 10.000 g Added mass 2 measurement: Added mass 2 5.000 g Air temperature 26.0 C Air pressure 1013.25 mB Air density 1.1799 kg/m^3 Speed of sound 346.7 m/s
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