Description

Experience powerful, precise and dynamic sound reproduction with the Anthem STR Power Amplifier, a flagship two-channel power amplifier designed for demanding high-end stereo systems.

Delivering an impressive 400W per channel into 8Ω, 600W into 4Ω and up to 800W into 2Ω, the STR Power Amplifier provides tremendous power and control to drive even challenging loudspeaker loads.

Its true dual-mono architecture features two independently wound toroidal transformers, one dedicated to each channel, ensuring stable power delivery and excellent channel separation.

Combining Anthem’s proprietary cascoded complementary feedback input stage, 16 bipolar output devices per channel and Advanced Load Monitoring (ALM™) technology, the STR Power Amplifier delivers exceptional clarity, low distortion and long-term operational reliability.

Designed and manufactured in Canada, it is the ideal partner for the Anthem STR Preamplifier and other high-performance stereo preamplifiers.

Key Features

Flagship 2-Channel Power Amplifier: Designed for premium two-channel Hi-Fi systems.

Massive Power Output: 400W per channel at 8Ω, 600W at 4Ω and 800W at 2Ω.

True Dual-Mono Architecture: Two independently wound toroidal transformers provide dedicated power supplies for the left and right channels.

16 Bipolar Output Devices Per Channel: High-current Class AB output design supports demanding loudspeaker loads and dynamic musical passages.

Cascoded Complementary Feedback Input Stage: Proprietary input topology designed for reduced distortion, excellent linearity and superior bandwidth.

Advanced Load Monitoring (ALM™): Continuously monitors internal temperature, current and voltage to help protect the amplifier and connected speakers.

No Rail Fuses: Direct-connected amplifier sections help minimise output impedance and improve power availability.

Massive Toroidal Transformers: Low-impedance, low-noise power transformers designed for stable and continuous power delivery.

Soft Turn-On Technology: Sequence-controlled start-up reduces inrush current and helps prevent circuit breaker tripping.

Four Power-On Options: Manual, signal sensing, trigger control or combined trigger and signal sensing.

7-Inch Graphic Front Display: Displays power meter readings, operating status, temperature information and setup navigation.

High Signal-to-Noise Ratio: 121dB IEC-A for exceptionally quiet background performance.

Low-Distortion Performance: Engineered for accurate and transparent sound reproduction.

Premium Audiophile Connectors: High-conductivity speaker binding posts and balanced XLR inputs.

USB Firmware Updates: Rear-panel USB connection for firmware upgrades.

Available Finishes: Black and Silver.

Made in Canada: Designed, engineered and manufactured in Canada.

Complete Technical Specifications

1. Amplifier Performance

Specification

Details

Model

Anthem STR Power Amplifier

Product Type

Stereo Power Amplifier

Number of Channels

2

Amplifier Configuration

True Dual-Mono

Amplifier Class

Class AB

Power Output per Channel (8Ω)

400W RMS

Power Output per Channel (4Ω)

600W RMS

Power Output per Channel (2Ω)

800W RMS (maximum 3 seconds)

Continuous Power Measurement

20Hz–20kHz, less than 1% THD

Both Channels Driven

Yes

THD at 400W (1kHz)

0.0007%

THD at 400W (20kHz)

0.004%

IMD at 300W – ITU-R

0.0006% (19kHz + 20kHz)

IMD at 300W – SMPTE

0.0016% (60Hz + 7kHz)

Signal-to-Noise Ratio

121dB (IEC-A, reference 400W)

Frequency Response

20Hz–20kHz ±0.1dB

Power Bandwidth

91kHz (-3dB at 400W into 8Ω)

Slew Rate

30V/μs

Damping Factor

360 (20Hz–1kHz)

Channel Separation at 100Hz

101dB

Channel Separation at 10kHz

98dB

Input Sensitivity

2.1Vrms (400W into 8Ω)

Input Impedance (RCA)

10kΩ

Input Impedance (XLR)

15kΩ

Voltage Gain

29dB

2. Audio Inputs and Outputs

Connection

Details

Balanced Analogue Inputs

2 × XLR (Left and Right)

Unbalanced Analogue Inputs

2 × RCA (Left and Right)

Speaker Outputs

2 × Speaker Binding Post Pairs

Trigger Input

3.5mm Mini-Jack

Trigger Throughput

3.5mm Mini-Jack

USB Connection

Rear-panel USB port for firmware updates

Power Connection

IEC C18 Power Cord Inlet

Chassis Ground

Dedicated Chassis Ground Connection

Input Connection Notes:

Balanced XLR inputs are recommended for improved noise and hum rejection, especially over longer cable runs.

RCA inputs are available for preamplifiers without balanced XLR outputs.

The balanced inputs are disabled when a single-ended RCA input is connected.

3. Power-On and Control Options

Operating Mode

Description

Manual Power-On

Turn the amplifier on or off using the front-panel power button.

Signal Sensing (Auto-On)

Automatically switches on when an audio signal is detected.

Automatic Standby

Switches off approximately 20 minutes after the audio signal stops.

Trigger Control

Remote power control through an external trigger-equipped component.

Combined Trigger + Signal Sensing

Allows either an audio signal or trigger to switch the amplifier on, with trigger priority for switching off when configured.

Trigger Specifications:

Trigger Input: 5–24V AC/DC.

Trigger Throughput: Allows trigger signal distribution to another compatible component.

Supports 3.5mm mono and stereo trigger cables, subject to connected equipment compatibility.

4. Internal Construction and Technology

Component / Technology

Details

Power Supply Architecture

True Dual-Mono

Toroidal Transformers

2 Independently Wound Toroidal Transformers

Output Devices

16 Bipolar Output Devices per Channel

Total Output Devices

32 Bipolar Output Devices

Input Stage

Cascoded Complementary Feedback Input Stage

Input Devices

8 Low-Noise Bipolar Input Devices

Output Stage

Class AB

Protection Technology

Advanced Load Monitoring (ALM™)

Rail Fuses

No Rail Fuses

Start-Up Technology

Sequence-Controlled Soft Turn-On

Front Display

7-Inch Graphic Control Display

5. Power Consumption

Operating Mode

Power Consumption

Standby

310mW

Idle

65W

Typical Playback Levels

150W–300W

High Playback Levels

600W–1,100W

6. Power Requirements

Version

Power Supply Requirement

120V Version

108–132V AC, 60Hz

220–240V Version

198–264V AC, 50Hz

Power Supply Type

Single-Phase AC

Automatic Voltage

Not Supported

7. Physical Specifications

Specification

Details

Height

17.2cm (6-3/4″)

Width

43.2cm (17″)

Depth

47cm (18-1/2″), excluding power cord

Weight (Unpacked)

27.3kg (60lbs)

Available Finishes

Black and Silver

Country of Manufacture

Canada