SoundTube SM400i Surface Mount Speaker in White

The SM400i is a 4-inch, coaxial, ported speaker with a low-profile surface mount enclosure design for indoor/outdoor applications that delivers a consistent dispersion pattern (2 to 10 kHz, independently verified.) Mounting hardware isincluded and features a corrosion and theft resistant Stealth U-bracket for easy and secure installation. 


Nearly invisible from sightlines, the Stealth U-bracket includes one way fasteners for tool-free, theft-resistant security. SoundTube®’s custom engineered driver and electro acoustic network deliver high performance sound in a cost-effective surface mount speaker design. 


The SM400i speaker incorporates a five-position tap switch with transformer bypass position for simplified ordering and stocking. Corrosion and theft resistant U-bracket mount with safety cable, Euroblock connector, paint mask, terminal weather boot, and port plugs are icluded. Included port plugs can be used for added weather resisitance.

  • ColorWhite
    Manufacturer’s Suggested Retail Price 
    Manufacturer’s CategorySMi Surface Mount
    Height6.97 in / 177 mm
    Width/Diameter9.68 in / 245.9 mm
    Shipping Weight7.3 kg / 3.31 kg
    Carton Height9.5 in / 241.3 mm
    Carton Length11.75 in / 298.45 mm
    Carton Width9.25 in / 234.95 mm
    CertificationsCE, RoHS, UL1480A
    Enclosure PropertiesABS Glass Fiber Reinforced, Injection Molded, Ported
    Enclosure Volume154.7 cu in / 2535.08 cu cm
    Included AccessoriesEuroblock, Port Plug, Safety Cable, Terminal Weather Boot, U-Bracket
    Optional AccessoriesWhite Grille (GRL-SM400-WH)|White Bracket (AC-SM4-WH)|10″ Safety Cable (AC-SM-SC10)|White Weatherboot (WEATHERBOOT-S-WH)|Connector (EUROBLOCK)
    Source Inputs4 Pin 5.08mm Euroblock
    Crossover Frequency2.3 kHz
    Directivity Factor (Q) (Averaged 100Hz – 10kHz, @ 2kHz)3.7 and 3.9
    Directivity Index (DI) dB (Averaged 100Hz – 10kHz, @ 2kHz)4.9dB and 5.9dB
    Frequency Response (± 10 dB)76 Hz – 22 kHz
    Frequency Response (± 3 dB)97 Hz – 22 kHz
    Grille PropertiesAluminum, Powder-Coated
    Low Frequency Voice Coil1 in / 25.4 mm
    Low Pass Crossover12 dB per octave 2nd order
    Magnetically BoostedNo
    Max. Continuous Power RMS20W
    Max. Program Power35 W
    Minimum Impedance (Ω Ohms)3.7 Ω
    Mounting Depth7.47 in / 189.7 mm
    Network Type: High Pass12 dB per octave 2nd order
    Nominal Impedance (Ω Ohms)4 Ω
    Tweeter Driver1″ Convex Aluminum w/ BroadBeam® Waveguide
    Woofer Driver4″ Polypropylene
    Sensitivity dB @ 1W/1M82.5 dB
    Sensitivity dB @ 2.83V/1M85.5 dB
    Tap SelectorRotary Switch
    Transformer Options25 / 70.7 / 100 V, 4 Ohm direct
    Transformer Taps (25V/70.0V/100V)2.5W/20W/20W