B.audio B.amp mono power amplifiers

It’s not unusual for fathers to influence sons, I wouldn’t be writing this today if my dad had not had a passion for music and an interest in decent equipment to play it on. I still remember the day that he replaced a beautiful Bang & Olufsen music centre with a Linn Sondek and put on the copy of JJ Cale’s Naturally that was the soundtrack in our house at the time. That was probably when the bug struck me. I’ve been living with the consequences ever since but I think I have it under control. B.audio was formed by brothers Cédric and Sébastien Bermann but this wouldn’t have come to pass if their father Gérard had not been a music and technology enthusiast.

The electronics that they make are not typically French in appearance but they are made in the Alsace region of France, which is perhaps close enough to Germany to explain the understated styling. There are two full ranges in the catalogue with DACs preamps and power amps in each plus the new Alpha One streaming amplifier launched for this season. The B.audio B.amp mono is the range topper when it comes to power amplifiers, the reference in all respects.

Vive la resistance

B.amp mono is as the name suggests a single channel amplifier built around a fully balanced circuit that’s specified to deliver up to 500 Watts into a four Ohm load and 300W into a typical eight Ohm resistance. Few if any loudspeakers have a linear impedance but these ratings suggest that the B.amp mono will be capable of powering pretty well all but the most extreme models on the market. Given this high power the casework is strangely devoid of heat sinking and while you can spot two rows of the stuff under the grille they aren’t very large and not a great deal of heat comes off the amps.

The Bermann brothers mention a number of technologies that they have used in the B.amp mono including circuitry that “reduces the crossover distortion below the measurement threshold”, which given that crossover distortion is the reason why Class A amps (which don’t have it) sound so nice, has to be a good thing. They also mention intelligent output drive which uses local feedback to “allow perfectly linear operation under all conditions”, this is apparently why heat output is lower than expected.

The B.amp mono also uses a Class A push-pull driver stage to deal with return currents from the loudspeakers and over size output transistors to provide a high current reserve with which to drive them. This stage is designed to insulate the amplifier from return currents caused by back EMF (electromotive force) produced by the loudspeaker crossover, these are known to have a negative influence on sound quality yet few amp makers mention this particular issue.

The design of the B.amp monos is simple and clean, Nordic in fact, with the bare minimum of connections and switches. Those that are included however are of the highest quality, input is via XLR only and output to the loudspeakers handled by a pair of WBT Nextgen terminals that accept banana plugs, spades and bare wire. The button that sits flush with the front panel has two LEDs beside it, the bottom one is on whenever the unit is in standby, both light up as the amp stabilises and the top one remains on when the amp is powered up. Fit and finish are superb. The grey of the wrap looks like Nextel and the anodised silver fascia is precision incarnate.

Caressing your ears

In the system driving Vivid Audio Kaya S12 loudspeakers the B.amp monos brought a precision and delicacy to the sound that was a delight, even when cold they have an ease that lets the melody float into the room as if on a breeze, the vocals caressing your ears and brushing away your cares. It became clear quite quickly that the B.amp monos are a bit special, they do micro and macro dynamics so well that it seems like there’s a lot more going on in the music than usual, in fact they clarify what’s going on so well that you can appreciate it that much more easily. It’s a defogging of sorts, an opening up of the background sounds alongside an ability to deliver the impact of the major sound sources in the mix. Their dynamic range is clearly very wide indeed.

The separation of instruments and of the notes from those instruments, including voices, is in the premier league. The B.amp monos are most definitely high end when it comes to transparency, this term is bandied around so much that it has lost its power, but when you hear something that gives you so much of what’s in the recording there is no more apt a description. It means visceral power behind electric instruments and seriously deep bass extension that’s full of shape and graduation, these amps are very sharp instruments that have no sharp edges save for those on the recording.

I really like the way you get speed without any sense of hurry, nor blurring of leading or trailing edges, a good drum recording such as that on The God In Hackney’s ‘Interstate 15’ reveals superb attack and natural reverb, it’s spacious and immediate which makes the sound extremely real indeed. There is no apparent change in character with level either, the Vivids aren’t a particularly difficult load of course but they reveal such limitations when they exist. Not here though, here you get dynamic drama from recordings that usually sound restrained. This happened with the Svaneborg Kardyb album covered last month which generally burbles along within a seemingly limited dynamic envelope, it seems however that my regular amplifier just couldn’t process the dynamic changes in the recording. Hearing it in full effect like this was quite an eye opener.

Class act

While the B.amp monos have some of the characteristics of a Class D amp, such as speed and the ability to start and stop with precision, they deliver a naturalness and depth of resolution that no such design has ever revealed in my system. They lack the slightly thick, cuddly sound found with many Class AB designs but retain the body and substance that the best of breed exhibit. It’s a presentation that is at once both fluid and analytical, a real best of both worlds combination that allows acoustic instruments in particular to really shine. Drums, pianos and voices all have a life and realism that is inspiring. Take Beck’s version of ‘Everybody’s Gotta Learn Sometime’, a great take on the Korgis’ hit, here the voice is startling in its presence and immediacy.

I tried the B.amp monos with my reference PMC twenty5.26i speakers but this wasn’t a happy partnership, the result being too lean for my tastes, however when the new Bowers & Wilkins 801 Signatures turned up things got a lot more interesting. These are rather special loudspeakers and the pairing with the B.audios proved a near perfect match, the sound was taut, clean and locked down in terms of timing and resolution, everything was laid bare and yet the music came first. The amps helping to clarify the way that the kick drum sits behind the first note of the bass riff in Laura Marling’s Soothing, and the depth of impact to the same drum on another The God in Hackney track, ‘Frozen Western’, here the openness of the percussion and piano, the brushes on the snare and the vivid overall sense of restrained power brought a whole new dimension to the track.

Unadulterated

The really nice thing about these amplifiers is that they bring out the best in all manner of recordings, you don’t need to stick to audiophilia to enjoy them. ‘How Much a Dollar Cost’ by Kendrick Lamarr wasn’t made for hi-fi nuts but it was very carefully put together despite the fact that most listeners will only hear it from MP3. It has a very low bass line and a superb drum sound which must have taken some time to get sounding so good. But it was Joni Mitchell’s ‘Don’t Interrupt the Sorrow’ that delivered the killer blow, the off kilter rhythms made clear and the voice piercing straight to the heart without even seeming to try brought a tear to my eye, it’s a masterpiece.

Cédric and Sébastien have surely made their father proud with the B.amp monos. These amplifiers are exemplary, a reference point that needs to be on your bucket list of must-hear components. They have power, speed and resolution down to the finest details of dynamics and timbre, qualities which when combined reveal the full glory of the music in no uncertain style.

Technical specifications

• Type solid state mono power amplifier
• Analogue inputs One pair balanced(via XLR)
• Analogue outputs One pair of speaker taps (via 5-way binding posts)
• Power output 300Wpc @ 8 Ohms, 500Wpc @ 4 Ohms
• Bandwidth > 200kHz
• Sensitivity 1v RMS
• Distortion THD < 0.0005% (1–100W, 8 Ohms).
• Dimensions (H×W×D) 112 × 450 × 385mm
• Weight 20kg
• Price £25,950/pair

Manufacturer

B Audio SAS

www.b-audio.com

+33 6 51 03 84 93

UK distributor

Reference Audio Ltd

www.referenceaudio.co.uk

+33(0)1376 526070

Back to Reviews

Read more B Audio reviews here