The Bryston 4B³ is a dual channel (stereo) amplifier internationally acclaimed as being suited for the finest and most sophisticated sound systems. It is Bryston's most popular Cubed Series model winning SoundStage Network's 2017 Products of the Year Award.
A rarified few components in audiophile lore have become so ubiquitous that nearly every music lover once had, lusted after, or if they're really lucky, currently owns one. One such legend is the Bryston 4B. This product has been manufactured continuously (though often refined) since 1978. Currently this venerated amplifier is on its 6th generation, and it's never been better. Now rated at 300 watts per channel into 8 ohms, (and upwards of 500 into 4 ohms), this true dual-mono amplifier is powerful enough for practically any speaker, yet it's priced to remain within reach. The degree of clarity, power, nuance, and outright truthfulness of this amp is stunning. If you've always wanted one, maybe now is just the right time.
"The 4B³ is a control freak in terms of grabbing hold of your speakers' drivers and maintaining bass control, depth and power."Edgar Kramar, Audio Esoterica
"These dig right to the heart of the music and result in one of the best all-round power amplifiers I have encountered at this price."Adam Smith, Hi-Fi News & Record Review
A significant part of the design criteria for the new Cubed series was to develop amplifiers that would maintain an ideal power curve from the first watt to the last. Most amplifiers exhibit a power curve where the best noise floor, drive capability and distortion are acheived from about 1/3 power and up. The new Bryston Cubed series amplifiers maintain their ideal power curve starting right from the first watt.
Achieving this starts with a number of design approaches:
Most class-AB amplifierrs have sufficient bias to prevent primary crossover distortion, but secondary crossover distortion is caused by insufficient speed in the driver transistors. The Cubed Series uses very fast drivers to help prevent this, as well as proprietary technology. Bryston's Quad Complementary Output design vastly reduces the capacitance seen by the driver transistors, virtually eliminating storage delay in the output stage that could contribute to nonlinearities in the zero-crossing region.
The clarity of Bryston's designs is enhanced at low listening levels by pushing the noise floor far below the signal level, improving the silence between the notes and enhancing the clarity of the music at low power levels.
Bryston amplifiers are perhaps the only designs to concentrate so much effort at reducing HF distortion artifacts, and the results are remarkably flat THD-with-frequency curves, sho frequency curves, sho frequency curves, showing almost no tendency to wing almost no tendency to increase distortion as frequency rises. This has the effect of reducing overall haze, helping to pull the quietest passages out of the background.
Additionally, the new Cubed Series employs highly effective RF employs highly effective RF rejection in the power supplies, which traps and eliminates radio-frequency hash from either interfering with or emanating from the amplifier via the power cable or signal cables.
|Dimensions||Inches: 17 or 19 W x 6.3 H x 15.5 or 17.75 (with front handles) D|
|Weight||42 lbs | 19 kg|
|Frequency Response:||<1hz - 100khz: -3db|
|THD+N (20Hz-20kHz @ Rated Power, 8Ω):||<0.005%|
|Power Output (per channel):||300W @ 8Ω | 500W @ 4Ω|
|Input Impedance:||Unbalanced 7.5kΩ|
|Balanced 30kΩ+ / 6kΩ-|