Anthem STR Stereo Power Amplifier


400 Watts x 2 Channel Power Amplfier

Anthem have produced the STR Power Amplifier, which is aimed to be the beating heart of a world-class 2-channel sound system. It delivers massive power generation, with audiophile-quality output in a smartly designed component. Designed, engineered and Crafted in Canada, the STR Power Amplifier delivers 400 Watts/channel into 8 ohms with both channels driven, a massive 600 Watts/channel into 4 ohms (both channels driven) and 800W in 2 ohms, for true no-holds-barred performance.

Inside, the STR Power Amplifier uses two colossal transformers and multiple high-current output devices so the most subtle details and dynamic peaks are handled equally well. Outside, its beautifully designed cosmetics, including a 7-inch graphic control display and secure, highly conductive audiophile connectors provide a perfect match to the STR Preamplifier.

Cascoded Complementary Feedback Input Stage

The STR Power Amplifier benefits from our proprietary input topology — a unique departure from the classic differential input stage. Eight low-noise bipolar input devices are configured in a complementary active-load cascoded feedback arrangement for reduced distortion, exceptionally linear response and superior bandwidth. Transistors in critical stages are hand-selected and matched for lowest possible distortion.

Sixteen Bipolar Output Devices Per Channel

Anthem engineers incorporated sixteen bipolar output devices per channel, resulting in peak production that is effortless and instantaneous, cinching even the most challenging material. The use of multiple bipolar output devices in class AB configuration also dramatically reduces distortion while ensuring extreme linearity, extensive bandwidth, and stress-free reliability. Experience the immense dynamics of up to 800 clean watts delivered into demanding 2-ohm loads, or 400W into 8 ohms/600W into 4 ohms continuously and with both channels driven.

Massive Toroidal Transformers

Conservatively rated, in a low-profile design shaped to minimise hum, the low-impedance toroidal power transformers — one for each channel — make no sacrifices when it comes to delivering a continuous supply of pure, clean, low noise power. As well, both the power supply impedance and internal cabling inductance are minimized to deliver a clear path for maximum power. The amplifier channels are thus able to deliver stable, continuous power at maximum output without affecting one another, even when driving the lowest impedances. While some amplifiers oscillate or run out of power when driving lower impedance loads, the STR Power Amplifier remains perfectly stable under all conditions.

  • Soft Turn-On

    A sequence-controlled soft turn-on significantly reduces power line transients and in-rush current during start up, thereby preventing accidental tripping of circuit breakers.

  • No Rail Fuses

    The amplifier sections are Direct Connected to the power supply capacitor bank. This keeps output impedance remarkably low while making more power available to the amplifier. Even when driving lower or complex impedance loads, the result is audibly superior performance.

  • Power On/Off Options

    In addition to the traditional options for power-on, the STR Power Amplifier allows trigger mode and audio signal sensing to be combined so you would never need to think about turning the amplifier on or off manually. This can be useful when using a preamp with Home Theater Bypass mode together with a surround sound processor in the same system.

  • The Crafted in Canada Difference

    The STR Power Amplifier is designed, engineered and manufactured in Canada and is part of premium STR Series by Anthem, the leader in audio power and control.


  • 400W / 600W / 800W continuous into 8 /4 /2 ohms, both channels driven
  • Cascoded complementary feedback input stage
  • Sixteen bipolar output devices per channel
  • Dual Mono Design
  • Massive toroidal transformers
  • Soft turn-on
  • Four power on/off options
  • No rail fuses
  • Advanced Load Monitoring Technology


  • Output (per channel, continuous, 20 Hz – 20 kHz, <1% THD) – 400 W (8Ω), 600 W (4Ω), 800 W* (2Ω)
  • THD (400 W) – 0.0007% (1 kHz), 0.004% (20 kHz)
  • IMD (300 W)
    • ITU-R (19 kHz + 20 kHz) – 0.0006%
    • SMPTE (60 Hz + 7 kHz) – 0.0016%
  • SNR (IEC-A, ref. 400 W) – 121 dB
  • Frequency Response (20 Hz – 20 kHz) – ± 0.1 dB
  • Power Bandwidth (-3 dB at 400 W into 8 ohms) – 91 kHz
  • Slew Rate – 30 V/μs
  • Damping Factor (20 Hz – 1 kHz) – 360
  • Channel Separation – 101 dB (100 Hz), 98 dB (10 kHz)
  • Input Impedance – 10 kΩ (RCA), 15 kΩ (XLR)
  • Input Sensitivity (for 400 W into 8Ω) – 2.1 Vrms
  • Voltage Gain – 29 dB
  • Dimensions (H X W X D) – 17.2 x 43.2 x 47 cm
  • Weight – 27.3 kg

Check out some reviews for the STR series here – Anthem STR Reviews

Check out the brochure for more information – Anthem STR Power Amplifier Brochure / Dimensions / Manual

Check out our first look unboxing video:



Black, Silver

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