B.amp

Reviewer: Srajan Ebaen
Financial interests: click here
Sources: Retina 5K 27" iMac (4GHz quad-core with Turbo boost, 32GB RAM, 3TB FusionDrive, OSX Yosemite. iTunes 14.4), PureMusic 3.02, Audirvana 3, Qobuz Hifi, Tidal Hifi, COS Engineering D1, Denafrips Terminator, Soundaware D300Ref as USB bridge/SD transport, Jay's Audio CDT2 MkII & DAC2-SE
Preamplifier: Nagra Classic, Wyred4Sound STP-SE Stage II, COS Engineering D1, Vinnie Rossi LIO (AVT module)
Power & integrated amplifiers: Pass Labs XA30.8; FirstWatt SIT1 monos, SIT3. F5, F6, F7; Goldmund/Job 225; Wyred4Sound mINT; Nord Acoustics NC500 monos; LinnenberG Audio Liszt monos, Bakoon AMP-13R
Loudspeakers: Audio Physic Codex; Cube Audio Nenuphar; Kroma Audio Mimí; Albedo Audio Aptica; EnigmAcoustics Mythology 1; Boenicke Audio W5se; Zu Audio Druid V, VI & Submission; German Physiks HRS-120; Eversound Essence; Fram Midi 150
Cables: Complete loom of Allnic Audio ZL 3000; Zu Event; KingRex uArt double-header USB cables; Tombo Trøn S/PDIF; van den Hul AES/EBU; AudioQuest Diamond glass-fibre Toslink; Black Cat Cable redlevel Lupo; Ocellia OCC Silver
Power delivery: Vibex Granada/Alhambra on all source components, Vibex One 11R on amps/sub
Equipment rack: Artesania Audio Exoteryc double-wide 3-tier with optional glass shelves, Exoteryc Krion and glass amp stands
Sundry accessories: Acoustic System resonators
Room: 4 x 6m with high gabled beam ceiling opening into 4 x 8m kitchen and 5 x 8m living room, hence no wall behind the listening chairs
Review component retail: €14'900

B.audio. Be audio. Be different audio.

When the French team around the Bermann family introduced themselves at the newcomer's exhibit of Munich HighEnd 2018, they premiered a DAC with novel topology. Following up with an amplifier of equal uniqueness must have been daunting. In that sector, hasn't all of it been there and done that already? But here comes the B.amp.

Cédric Bermann: "The B.amp was developed in conjunction with our DACs and to work as a logical complement for the B.dpr with analogue volume control. Our goals were fine natural sound with perfect soundstage reproduction and the power and speed to operate the most difficult speakers; and our brand aesthetic of a discreet modern design for successful integration into a living environment. To combine these often contradictory features, we decided to go for a bridgeable architecture. Although we designed the B.amp for use in stereo, it is basically a fully balanced monaural design executed in true dual mono which can be easily switched into high-power mode."

"We opted for reasonable yet sufficient power of 120wpc in stereo—300W in mono—with a current capacity 4 x higher than common. We started R&D with numerous computer simulations and real-world measures as the first steps to obtaining great overall results. This phase was followed by intensive listening tests. We settled on class AB bias to allow great power with reasonable draw and dimensions. Then we strove to remove the drawbacks of class AB, i.e. fight its crossover distortion with our proprietary push/pull Intelligent Output Drive. It consists of an innovative 6-transistor driver stage which not only allows better control over the output transistors to reduce distortion but guarantees perfect immunity to the feedback currents generated by the loudspeakers. Four pairs of high-power bipolar output transistors per channel provide important power reserves. Thanks to these developments, there is no measurable crossover distortion where the output stage behaves like class A without its drawbacks." These claims mirror Hegel's but without their complex feed-forward error correction circuity.

"All other stages including the driver for the output stage operate in actual class A.

"Other optimizations include direct-coupled operation without signal path capacitors for bandwidth beyond 200kHz; the use of 105µm copper traces to guarantee higher current capacity for better control at low frequencies; and a linear power supply with 2 x 400VA toroidal transformers fully separated from the amplifier boards to achieve performance like an outboard power supply without the need for two chassis."