Bryston 7B³

Two completely separate channels, two independent power supplies, zero compromise on loudspeaker control: this is the philosophy that has driven Bryston’s Cubed series since its introduction in 2016. The 7B3 embodies this approach in its most accomplished form, with a specially wound toroidal transformer that provides a generous power reserve of 600 watts into 8 ohms. Each unit leaves the factory in Peterborough, Ontario, after 100 hours of burn-in and individual quality control documented by a measurement certificate.

A redesigned input stage with the Salomie circuit

The main technical evolution of the Cubed series lies in its patented input circuit, the result of a collaboration between the engineering team led by Christopher Russell and Dr. Ioan Alexandru Salomie. This architecture uses twelve active components arranged in a novel configuration that provides the first 6 dB of gain while matching the input impedance to virtually any preamplifier.

The result is measurable: distortion at the input stage drops below 0.0001%, i.e. less than one-thousandth of a percent. This linearity leads to effective rejection of electromagnetic and radio-frequency interference, a valuable advantage in environments where digital equipment and wireless networks coexist.

Quad-Complementary topology and optimized class AB

The output stage uses the Quad-Complementary topology developed by Bryston for the SST² generation. This circuit improves linearity by eliminating the harsh harmonics often associated with solid-state amplifiers. The distribution of residual harmonics is similar to that of a class A amplifier, but with total distortion (THD+N) below 0.005% across the entire audible spectrum at full power.

Class AB operation keeps temperatures moderate thanks to the passive heatsinks integrated into the chassis. The absence of a fan guarantees complete silence, an important criterion for nearfield listening where monoblocks naturally find their place.

Power supply and current capability

The 7B3 differs from the stereo 4B3 through its power supply dedicated to a single channel. Its toroidal transformer, wound to specifications unique to this model, delivers higher efficiency that allows for larger instantaneous current draws. Power climbs to 900 watts into 4 ohms, a ratio that attests to its ability to maintain voltage under complex loads.

This energy reserve proves useful with speakers that have varying impedance or low sensitivity, and also for reproducing the dynamic peaks of orchestral or percussive recordings without audible compression. The signal-to-noise ratio reaches -117 dB on the unbalanced input and -119 dB on the balanced input—figures that place the noise floor well below the threshold of audibility in most setups.

Integration and implementation

The rear panel includes a switchable XLR input and RCA input, as well as a two-position gain setting (23 dB or 29 dB). The higher sensitivity of the 29 dB mode suits sources with modest output levels or passive preamplifiers, while the 23 dB setting is better matched to home theater processors whose outputs often reach 2 volts or more.

A 12-volt DC trigger allows automatic power-on from a preamplifier or home automation system. The microprocessor-controlled SoftStart circuit staggers current inrush at power-up to prevent nuisance tripping of circuit breakers, even when several monoblocks share the same electrical circuit. In standby, power consumption drops below 500 milliwatts.

Construction and finishes

The machined and anodized aluminum chassis provides both electromagnetic shielding and heat dissipation. The output binding posts accept banana plugs, spades, and bare wire; their upward orientation makes it easier to connect cables from the sides. The 24 kg weight reflects the generous power supply and the overall mechanical solidity.

Two front panel widths are available: 17 inches for discreet installations, or 19 inches with integrated front handles for easier handling, though not intended for rack mounting. Silver and black finishes cover the most common aesthetic preferences.

Warranty and long-term support

Bryston offers a twenty-year parts and labor warranty on its analog amplifiers, transferable in the event of resale. This coverage reflects a design philosophy focused on durability and reparability: accessible discrete circuits, documented components, and after-sales service provided directly by the manufacturer in Canada. The measurement certificate supplied with each unit makes it possible to check any potential performance drift later on.

Technical specifications

Power and performance

• Output power
  • 600 W into 8 Ω
  • 900 W into 4 Ω
• Switchable gain selection: 23 dB, 29 dB

Audio characteristics

• Frequency response: below 1 Hz – 100 kHz (–3 dB)
• Total harmonic distortion + noise: less than 0.005% (20 Hz – 20 kHz at 600 W into 8 Ω)
• Signal-to-noise ratio
  • RCA input: –117 dB
  • XLR input: –119 dB

Connectivity and inputs

• Input impedance
  • Unbalanced: 7.5 kΩ
  • Balanced: 5 kΩ per phase

Design and construction

• Machined and anodized aluminum chassis
• Natural convection cooling (silent operation)
• Patented Salomie circuit for absolute control and detailed sound

Features

• Extremely low standby consumption: less than 500 mW
• SoftStart progressive startup prevents circuit breaker tripping
• DC trigger for automated power on / off
• Legendary 20-year Bryston warranty

Dimensions and weight

• Dimensions (W x H x D)
  • 43.2 cm version: 43.2 x 14.7 x 39.4 cm
  • 48.3 cm version: 48.3 x 14.7 x 45.2 cm (with front handles)
• Weight: 24 kg

Available options

• Front panel width: 43.2 cm, 48.3 cm (not rack-mountable, 48.3 cm version with front handles)