OSD Audio SMP300 Mono Subwoofer Amplifier - 300W

OSD Audio  |  SKU: SMP300
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Sale price £499.00 Regular price £599.00
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Description

Enhance your home audio experience with the OSD Audio SMP300, a powerful 500W mono-channel Class D subwoofer amplifier engineered to deliver deep, clean bass with outstanding efficiency.

Perfect for home cinema systems, custom installations, or high-end two-channel audio setups, this compact yet robust amplifier is tailored for audiophiles who want to power a passive subwoofer with precision and control.

With its rack-mountable design and advanced signal sensing, the SMP300 integrates seamlessly into AV systems.

Whether you're upgrading a home theatre or adding low-frequency impact to a multi-room setup, this amplifier offers versatile performance with intuitive controls and flexible inputs.

FEATURES

  • High Power Output: Delivers up to 500W peak and 300W RMS, driving even large passive subwoofers for room-filling bass.
  • Class D Efficiency: Class D digital amplification ensures cooler operation and reduced power consumption without compromising on performance.
  • Variable Crossover & Phase Control: Fine-tune your bass response to suit your room acoustics and speaker setup with adjustable crossover and 0–180° phase switch.
  • Multiple Input Options: Includes both line-level and speaker-level inputs, making it compatible with a wide range of audio systems.
  • Auto-On Signal Sensing: Automatically powers on when a signal is detected and shuts off after inactivity, improving energy efficiency and convenience.
  • Rack-Mountable Design: Fits neatly into standard AV racks with removable side brackets, perfect for professional or custom home installations.
  • Subwoofer EQ Switch: Enhances low-end performance with a tailored EQ setting for even deeper bass output.
  • Heavy-Duty Build Quality: Solid construction with reliable components ensures long-term durability and consistent performance.
  • Quiet Fan Cooling: Internal fan keeps the amp cool under load while maintaining quiet operation.
  • Protection Circuitry: Built-in safeguards protect against short circuits, overheating, and overloading, giving you peace of mind.

Specifications

  • Amplifier Type: Subwoofer
  • Amplifier Class: Digital Class D
  • Channels: 1
  • Power Output: 500 Watts @ 4 Ohm
  • Power Handling: 8 Ohm RMS Rating (Watts): 150 Watts
  • Power Handling: 4 Ohm RMS Rating (Watts): 250 Watts
  • Frequency Response: 20Hz-160Hz +/-1dB THD: 1%
  • Variable Crossover: 35Hz-180Hz
  • Variable Phase Switch: 0 To 180 Degrees
  • Impedance: 8 Ohm And 4 Ohm Stable
  • Signal To Noise Ratio: 95 dB
  • 12V Trigger Mode
  • Inputs: Speaker (High) Level / Signal (Low) Level RCA
  • Rack Mountable: 1U Rack Space Style / Mounts Included
  • Dimensions (L x H x D): 413mm x 76mm x 235mm
  • Weight: 3.2kg
  • Warranty: 2 Years

What You Get

  • 1 x SMP300 Amplifier
  • 1 x Power Cable

Downloads

Payment & Security

Payment Methods

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Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

2 Years Warranty + 60 Day Returns

K&B Audio are authorised retailers for OSD Audio. Your purchase comes with a 2 Years warranty, expert help on hand and you get 60 day returns window in case you're not 100% happy with the product.

Frequently Asked Questions

Do you price match?

Yes, we will try our best to price match for you - but as a small independent company, we can't always guarantee it.

Please submit a price match request here.

We will price match where possible provided that the competitor is a like for like UK VAT registered company, they must be an authorised retailer, the product must be in stock and not on clearance.

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