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Visually there’s nothing like these components in all of audiodom. The striking designs feature heavy gauge grey-ish aluminium panels folded to form the fascia and sides. The top segment is pattern cut into a ventilated grid section atop a layer of stainless steel mesh which protects the innards. Preamplifier and monoblocks look almost identical save for the former’s volume knob. The monos embrace Morrison’s preferred class A mode of operation. Pure Audio quote 65 watts at 8Ω of pure class A power and the amps use three pairs of high-current bipolar transistors in the output stage. Having owned and reviewed solid state class-A amps from Gryphon, Musical Fidelity and Pass Labs, I found the Reference monos to run a tad too cool in light of their claim. Thirty seconds of heatsink caressing those other amps and your hands scald and scar up with permanent heatsink patterns. But with the internal real estate almost half taken up by heatsinks here, the extension of same by the chassis itself plus ultra-quiet fans in full-time operation, the claim may indeed be true. And I must stress just how quiet the fans were at least on my review samples. You won’t hear them at all from the listening position or even much closer. That means large fans running at slow speed and indicates good design.

"There's an article on our website discussing just this. The market is full of 'class A' products which are not truly class A. As a general rule you should expect a class A mono amplifier to dissipate a minimum of twice its rated power at idle or four times for a stereo design. In our monos each amplifier dissipates around 150 watts at idle. The heatsink temperature reaches around 55°C. The low speed fans substantially increase the heatsink efficiency."

The Reference mono rear panel is an example of good layout and simplicity. Aside from the IEC socket you’ll find high quality RCA inputs and the wonderful Cardas binding posts which allow easy hand tightening while providing great surface contact for spades though banana plugs need not apply. A small toggle switches the fascia’s operational light off/on and a 12-volt trigger in/out arrangement provides auto turn-on when connected to Pure Audio’s Control preamplifier. As stated already the power rating is 65wpc with 30 amps of current on tap while the frequency response is claimed to be flat from 10Hz-100kHz with 0.01% distortion under "normal operation". Input impedance is 100kΩ and an easy load for any preamplifier. The monoblock amplifiers weight 16kg each.

Morrison expands. "My design approach is to acknowledge the fact that there's no such thing as a perfect amplifier. All active devices introduce some nonlinearity. Rather than fight this I have learnt to work with it, understanding how the nonlinearities can be both minimized and made to work in harmony with the music. Both the Control preamplifier and mono amps rely on power supplies tailored to provide a very low noise closely coupled power source. This is tightly integrated with the ground design. Circuit topologies are kept as simple as possible and parts of course are of as high quality as possible. The products are designed to be highly reliable and to have a very long service life. They are also very easy to service and utilize a plug-in modular construction that allows for future upgrades when advances become available. Used as a system the combination is intended to offer a very simple user interface, part of our pure design focus. Our website features a number of pertinent articles on this and other subjects."

Equal simplicity and elegance feature in the dual mono Control preamplifier. And sparseness really was the aim with this design. There’s no input switching, muting circuit (turning the knob to zero puts the preamp in standby), balance control or noisy microprocessor of any kind. All these elements were deemed undesirable by potentially affecting sound quality and purity. The volume pot is a minimalist 32-step attenuator featuring non-magnetic Vishay Dale resistors. According to Pure Audio the purity of the pot’s design allows the signal to pass unscathed with "nothing added, nothing taken away".


The non-switching input feature is a bit of a doozy. When an input sees signal—and only then—is it automatically activated and selected. Hit go on your CD player. Once the signal is sensed, its input powers up. This in turn activates the monos which remain in standby until signal knocks on their doors. There’s thus a slight delay while all of this transpires. On occasions the first second or so of music may be missed. And I didn’t try feed two signals at once for fear of opening a portal into an anti-matter dimension.