Bryston - 4B³ - Stereo Power Amplifier

The 4B³ is one of Bryston’s most iconic stereo amplifiers, combining immense control, dynamic authority, and transparency into a design trusted by both audiophiles and recording professionals around the world. Built around Bryston’s Cubed Series platform and patented Salomie input stage circuitry, the 4B³ delivers exceptional clarity and musical realism while maintaining the reliability the brand is famous for.

What makes the 4B³ especially compelling is how effortlessly it balances power with refinement. Bass remains tight and controlled, vocals sound open and natural, and complex musical passages stay composed even at demanding listening levels. Its fully balanced architecture and convection-cooled chassis contribute to extremely low noise and long-term operational stability without relying on noisy fans or unnecessary complexity.

With 300 watts per channel into 8 ohms and up to 500 watts per channel into 4 ohms, the 4B³ has the current delivery and headroom to confidently drive a wide range of high-end loudspeakers while preserving a relaxed and highly engaging presentation.

Available in Silver or Black finishes.

FEATURES

• Reference Stereo Power Amplifier
• Bryston Cubed Series Technology
• Patented Salomie Input Stage Circuitry
• Balanced XLR and Single-Ended RCA Inputs
• Switchable Gain Settings (23dB / 29dB)
• Fully Convection Cooled Design
• No Fans or Moving Parts
• Machined and Anodized Aluminum Chassis
• Regulated Power Supplies for Voltage Gain Stages
• SoftStart Microprocessor Controlled Startup Circuit
• DC Trigger Input for Automated Power Control
• Dual Binding Post Pairs
• Ultra Low Noise and Distortion Design
• Designed and Manufactured in Canada
• Legendary 20 Year Bryston Warranty

SPECIFICATIONS

• Amplifier Type: Stereo Power Amplifier
• Class of Operation: Class AB
• Power Output: 300W per Channel @ 8Ω / 500W per Channel @ 4Ω
• THD + N: <0.005% (20Hz–20kHz @ 300W, 8Ω)
• Frequency Response: <1Hz – 100kHz (-3dB)
• Noise:
  • RCA: -117dB
  • XLR: -119dB
• Input Impedance:
  • Unbalanced: 7.5kΩ
  • Balanced: 5kΩ / Leg
• Gain Settings: 23dB / 29dB Selectable
• Slew Rate: >60V/µS
• Damping Factor: >300 @ 20Hz (8Ω)
• Inputs: Balanced XLR / Single-Ended RCA
• Speaker Outputs: Dual Binding Posts
• Cooling System: Fully Convection Cooled
• Standby Power Consumption: <500mW
• Dimensions: 17” or 19”W x 5.25”H x 17.25”D
• Weight: 55 lbs / 25 kg
• Faceplate Options: Silver or Black
• Manufacturing: Designed and Manufactured in Canada