Anthem STR Power Amplifier

The STR Power Amplifier is the beating heart of a world-class sound system, a statement in unwavering performance. As our flagship power amplifier, it is engineered to deliver immense power and audiophile-quality output in a single, elegantly designed component.Designed, engineered, and Crafted in Canada, the STR Power Amplifier delivers 400 Watts/channel into 8 ohms, 600 Watts/channel into 4 ohms, and a staggering 800 Watts/channel into 2 ohms—all with both channels driven. This is true no-holds-barred performance, providing immense headroom and effortless dynamics.Inside, a true dual-mono design with two colossal transformers and multiple high-current output devices ensures the most subtle details and dynamic peaks are handled with equal authority. Outside, its beautifully designed cosmetics—including a 7-inch graphic control display and secure, highly conductive audiophile connectors—make it a perfect sonic and visual match for the STR Preamplifier.

The Purity of Dual Mono

The pursuit of sonic purity led to one conclusion: a true dual-mono design. The STR Power Amplifier features two colossal, independently-wound toroidal transformers—one for each channel. This meticulous engineering choice provides each channel with its own dedicated, uninterrupted power source, ensuring absolute channel separation and complete freedom from interference. The result is unyielding power, unwavering stability, and a soundstage with pin-point accuracy and stunning realism.

Sixteen Bipolar Output Devices Per Channel

To achieve absolute command over any loudspeaker, Anthem engineers incorporated sixteen bipolar output devices per channel. This meticulous design provides effortless, instantaneous peak production that confidently handles even the most challenging material. The use of multiple bipolar devices in a Class AB configuration dramatically reduces distortion while ensuring extreme linearity, extensive bandwidth, and long-term, stress-free reliability.

Intelligent Protection,
Uncompromised Sound

We believe in protecting your investment without ever compromising on performance. The STR Power Amplifier incorporates our proprietary Advanced Load Monitoring (ALM™) technology, a state-of-the-art system that continuously monitors temperature, current, and voltage to ensure peak performance and long-term reliability. Unlike conventional protection circuits, ALM is non-invasive, meaning it only engages under extreme conditions. This allows the amplifier to deliver its full dynamic potential without any audible interference, providing you with a sound that is as transparent as it is dynamic.

Amplifier Power Output

• 400 W per channel @ 8 Ω

• 600 W per channel @ 4 Ω

• 800 W per channel @ 2 Ω (max ~3 seconds peak)

• Rated 20 Hz – 20 kHz, <1% THD with both channels driven.

This makes it capable of driving very demanding speakers.

Audio Performance

• Total Harmonic Distortion (THD)

  • 0.0007% (1 kHz)

  • 0.004% (20 kHz)

• Signal-to-Noise Ratio (SNR)

  • 121 dB

• Frequency Response

  • 20 Hz – 20 kHz (±0.1 dB)

• Power Bandwidth

  • 91 kHz

• Slew Rate

  • 30 V/µs

• Damping Factor

  • 360

• Channel Separation

  • 101 dB (100 Hz)

  • 98 dB (10 kHz)

Input Specifications

• Input Sensitivity: 2.1 Vrms (for full 400 W output)

• Input Impedance:

  • RCA: 10 kΩ

  • XLR: 15 kΩ

• Voltage Gain: 29 dB

Power Consumption

• Standby: 310 mW

• Idle: 65 W

• Typical playback: 150–300 W

• High playback: 600–1100 W

Design Features

• Class AB stereo power amplifier

• True dual-mono design (separate transformers for each channel)

• 16 bipolar output devices per channel

• Advanced Load Monitoring (ALM) protection

• Balanced (XLR) and unbalanced (RCA) inputs

• High-current output stage for difficult speaker loads

Physical Specifications

• Width: 43.2 cm

• Height: 17.2 cm

• Depth: 47 cm

• Weight: 27.3 kg