The £32,000 Eon Art Boson integrated monophonic amplifier starts off pretty unique in the fact that it's a mono integrated amp, so each channel of your stereo source goes to one of the Boson. That's before we get into the realms of bi-, or even tri- amping. Additionally, the Boson is a hybrid amplifier using both Class A and Class D as well as mixing it up with solid-state and valves.

EON ART BOSON AMPLIFICATION

Each monoblock is equipped with its own valve preamp section that uses three E88CC JJ TESLA (6922 / 6H23N-EB) tubes, with the power section using five valves comprising a JJ TESLA 5AR4 /GZ34, one 12AX7, a pair of 6V6G, and a 0B2. A solid-state impedance adaption buffer circuit follows that along with a solid-state Class A input stage providing gain as well as managing and filtering the bandwidth before driving the Class D output stage. Overall, the result is 250 Wrms at 8Ω, 400 Wrms at 4Ω with only two transistors, says the Quebec-based brand. Other listed specs include THD + N @ 208 W RMS = 0.3494% and a measured frequency response of 20 Hz - 20 kHz at 0,853 dB.

A control circuit with an internal microprocessor makes various acquisitions and manages the parameters of the class D section, and the first three amplification stages (impedance adaptation, gain, filters). This, we are told, solves the usual problems of pairing class D circuits with valves. That control circuit is internally networked with two other microprocessors, one that manages the preamp section and the other that's tasked with volume control, source selection and infrared and Bluetooth remote controls as well as the link between the Boson blocks. Additionally, the Boson block is full of current, voltage, resistance and temperature sensors, all factors that have a significant effect on performance.

The capacitors used on the path of the audio signal are all from well-respected brands in the audiophile world, such as Amtrans, Clarity, Duelund, Mundorf and Solen. Eon Art says the use of capacitors is organised so that there is no phase rotation at the output. The Boson employs multiple ferrous electromagnetic shields and several Faraday cages of aluminium and copper to protect the more critical areas.

We are told that the Boson offers 20% more power and twice the power reserve than its little brother the Quark amplifier; which gives it even more bottom, says the manufacturer.

FUTURE PROOF

All of that tech can be easily pulled out, as the Boson block sports a drawer that contains the PCB. This not only provides easy access but enables future upgrades as well as replacement of components which makes the integrated monoblock pretty much future proof and an amp for life.

You can connect up to six Boson to the same source line via an internal Lundahl splitter, which can be bypassed when using the Boson in dual mono mode. Moreover, controlling all the amplifiers in a system is simple. Firstly, it can be done with the front buttons of any of the Boson in the system, with the others automatically copying the command. Alternatively, by remote control or even via your computer.

Eon Art has eschewed the use of relays and mechanical potentiometers for volume control, in favour of individual high stability, very high precision and medical-grade, thin metal film resistors, selected by transistors.

Standard inputs are four lots of RCAs. However, there is an optional input module that adds RCA, XLR, an MM phono stage and a DAC. There are no details as to what digital inputs the latter brings to the party.

PUT TO THE TEST

Each printed circuit board is subjected to rigorous automated testing after welding its components using specific computerised analysers. The equipment is then tested for endurance and stability over a twenty-four-hour period at full power under the eye of a 64-channel M300 Acquisition Center.

As well as listening to each Boson in a reference system, before it goes out, it is put through testing with an Audio Precision analyser to ensure it reproduces complex musical signals, says Eon Art.

Each step of the assembly and the qualitative process is documented and signed by the various stakeholders in a certificate which is then issued to the owner.

Finally, the 7mm brushed aluminium alloy chassis with quick access rail system, and 19mm solid front panel is the work of Oracle Audio -  those of Delphi turntable fame.

The whole unit sits on 20mm of Labradorite semi-precious stone and Soundcare feet. Scientiae in Servitium Artis, indeed.

For more information, head over to Eon Art.