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Niles OS5.3SI Stereo Input White Speaker and BTA-250 In-Wall Amplifier

Sorry, this product has been discontinued.

Niles OS5.3SI Stereo Input White Speaker and BTA-250 In-Wall Amplifier

OS5.3SI Stereo Input White Speaker

High Performance Indoor/Outdoor Loudspeaker. Exceeds military anti-corrosion specifications (MIL-STD-883D) Integrated mounting bracket.

BTA-250 In-Wall Amplifier

For audio installers and the do-it-yourselfer who need to add a two-channel stereo amplifier in homes or commercial spaces, Earthquake Sound gives to you the new BTA-250. Adding an audio zone with Bluetooth¬ģ capability has never been easier. This is a wireless in-wall amplifier kit that packs flexibility, power, and control into one very small and discrete package that can be used for both indoor and outdoor settings. The BTA-250 kit comes with the in-wall amplifier, B120R retrofit electrical box, 12‚Äď24 VDC power supply, and cable adapter.

This three input in-wall amplifier can accept signal through the front panel 3.5mm stereo mini jack, Ethernet port, or Bluetooth¬ģ connection. With the provided 12‚Äď24 VDC power supply and cable adapter, the BTA-250 can produce 50 WRMS per channel and can easily power a pair of ceiling, outdoor, or in-wall speakers. It is compatible with 4-Ohm and 8-Ohm systems and also features a front mounted volume control knob for added convenience.

OS5.3SI Stereo Input White Speaker


  • Woofer Technology
  • Integrated woofer/baffle assembly increases cone area to provide powerful bass output
  • 5" Mica-filled polypropylene cone is extremely rigid to reduce breakup and lower distortion
  • Butyl rubber cone surround damps resonance and provides exceptional durability
  • Dual voice coils deliver both left and right channels from one speaker
  • Tweeter Technology
  • Stereo Imaging tweeter array directs the high frequency sounds from both the right and left channels into a space from one speaker
  • Dual 1" UltraSilk domes with fluid-cooling and ultra-wide dispersion for clear and detailed high-frequencies


  • Impedance: 8 ohm per channel wired in stereo or 4 ohm with both channels wired together
  • Recommended amplifier power: 5W to 100W per channel
  • Frequency response: 85Hz - 21kHz +/-3dB
  • Sensitivity: 90dB for 2.83V pink noise
  • Dimensions (includes bracket): 12” high x 7-7/16” wide x 7-3/4” deep
  • 30.48 cm high x 18.89 cm wide x 19.68 cm deep
  • Includes integrated mounting bracket

BTA-250 In-Wall Amplifier


  • Flex Power 12–24VDC
  • Bluetooth® Compatible
  • 3.5mm Line Input
  • PoE (Power over Ethernet)
  • Balanced Audio In
  • Supports Cat 5/6
  • 20Hz–20kHz Frequency Response
  • Output Power:
  • 2 x 50 WRMS @ 4-Ohm
  • 2 x 25 WRMS @ 8-Ohm
  • THD: < 0.1% @ 1kHz
  • S/N: 95 dB @ 4-Ohm 1kHz
  • Input Impedance: 20 kOhm
  • Wireless Range: Up to 32.8 ft (10m)
  • Fits most standard single-gang junction boxes

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Why are you seeing the message now?

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Where can you get more information about Proposition 65?

Learn more from the California Office of Environmental Health Hazard Assessment (OEHHA) site here.