S series Plastic Speaker

S series Plastic Speaker

The Beta Three® S series is a series of professional coaxial plastic speakers perfectly suited for various portable and installed applications. The coaxial feature and the neodymium magnets utilized in this series significantly reduces the overall weight of the speakers and makes it extremely compact. The weather-resistant feature of the S series allows this system to optimize performance in both indoor and outdoor applications.

S400a - 4" Two Way Active Speaker
S400a - 4" Two Way Active Speaker
S400a - 4" Two Way Active Speaker
S400a - 4" Two Way Active Speaker
S400a - 4" Two Way Active Speaker


4" Two Way Active Speaker

Professional portable and installed plastic loudspeakers where high sound quality is required. Can be used in applications including sound reinforcement in Front of House and Foldback applications in Houses of Worship, Events, Clubs, Rehearsal Halls etc. The S Active Series is suitable for music and vocal reproduction in demanding applications. 


  • High output SPL and sensitivity
  • 2 x 4” high power transducers
  • 1 x 1” diaphragm compression driver
  • 120º x 120º controlled coverage pattern
  • Built-in power amplifier module
  • Master volume control
  • 2 x XLR connectors
  • Injection molded
  • Cabinet design for FOH use
  • Suitable for use as a main system with or without sub speaker augmentation
  • Portable system (stand), or permanent installation (wall, ceiling, under balcony)
  • Powder coated grill with foam backing
  • Comes with convenient mounting bracket
  • Available in black or white


Acoustical specifications
Frequency Response(-3db):
Max SPL @ 1m:
Dispersion (H x V):
120° x 120°
Compression driver:
1 x 1" HF
2 x 4" LF
Input/Output section
Input signal:
Balanced 20kΩ, Unbalanced 10kΩ
Input Connectors:
2 x XLR
Processor section
Crossover frequencies:
Power section
Total Power:
100W(RMS); 200W(MUSIC); 400W(PEAK);
Nominal Impedance (Ohm):
Voltage range:
AC 220V-240V~, 50/60Hz (or AC 110V-120V~, 50/60Hz)
Physical specifications
Dimension (W x D x H):
182 x 182 x 320mm / (7.2 x 7.2 x 12.6in)
Package Dimensions (W x D x H):
230 x 230 x 375mm / (9.1 x 9.1 x 14.8in)
Net Weight:
6 kg / 13.2 lb
Gross Weight:
7 kg / 15.4 lb

S400a Application

    S400a Installation

      S400a Parts

        S400a Cases

          S400a Collocation



              S400aβ3 S400a Datasheet 1.0S400a  200KB 2022-07-06 06:46:43
              β3_S400aPlastic_Speaker_Chinese_Manualβ3_S400aPlastic_Speaker_Chinese_Manual 1β3_S400aPlastic_Speaker_Chinese_Manual  2003KB 2018-07-12 02:25:39
              β3_S400aPlastic_Speaker_English_Manualβ3_S400aPlastic_Speaker_English_Manual 1β3_S400aPlastic_Speaker_English_Manual  2003.92KB 2018-07-12 02:25:39