This review page is supported in part by the sponsors whose ad banners are displayed below

This review first appeared in the July/August 2008 print issue of the Australian Hifi magazine. Because Edgar Kramer is on their staff as well as ours, we were given permission to syndicate his original review as adapted by Edgar for our global Internet audience. All images are the property of Australian Hifi or Classé. - Ed.


Reviewer: Edgar Kramer
Financial Interests: Click here
Source Digital: Metronome T-1i CD player with DAISy HE Remote Control
Preamp/Integrated: Supratek Sauvignon with NOS RCA and Bendix tubes; NuForce P9
Amplifier: NuForce Reference 9 V2 Special Edition monoblocks
Loudspeakers: Wilson Audio Specialties WATT/Puppy System 8
Cables: Digital: Cerious Technologies; Harmonic Technology Magic
Interconnect: Cable Research Laboratory (CRL) Gold with Bocchino XLR and RCA; Cerious Technologies; Harmonic Technology Magic and Truthlink Silver; DanA Digital Reference Silver; Eichmann eXpress 6 Series 2; Bocchino Audio Morning Glory; PSC Audio Pristine R30 Ribbon
Speaker: Cerious Technologies and Harmonic Technology PRO-9+ loudspeaker cables
Power: Cerious Technologies AC; Harmonic Technology Fantasy; Shunyata Research Diamondback, Eichmann eXpress AC power cables; PSC Gold Power MKII AC cable
Stands: Finite Elemente Pagode Signature equipment racks
Powerline conditioning: PS Audio P-300 Power Plant (digital equipment only)
Acoustic treatment: Fonic Designer panels and StudioCel bass traps
Sundry accessories: Burson Audio Buffer, Bright Star Audio IsoRock Reference 3, Bright Star Audio IsoRock 4 isolation platforms and BSA IsoNode feet; Bocchino Audio Mecado isolation diodes; Black Diamond Racing cones; Stillpoints ERS paper in strategic positions around DAC, Shakti On Lines; Densen CD demagnetizer; Auric Illuminator CD Treatment; ASC Tube Traps
Room size: 17' w x 35' d x 12' h in short wall setup, opens to adjoining kitchen
Review component retail: AU$12,000/ea.
It's one of the best endorsements in the world of high-end audio when a company's product is chosen by a world-leading recording studio as the in-house reference. So it is with the amplification behemoths on review here, the Classé CA-M400 monoblock amplifiers from Canada; Abbey Road Studios' amplifier of choice for a number of their famous recording rooms. In fact, the very pair at hand, prior to their arrival, were in situ at a Sydney-based studio where some months ago they performed amplification duties during the production of the Happy Feet soundtrack, amongst many others.
Upon receiving these amplifiers, I was struck straight off by the quality and solidity of the packaging. No mere cardboard boxes here. I'm talking about a
rib-reinforced box of plastic-type material that can not only take the unit's weight but also support and protect it against the clumsiest of couriers. What's more, unpacking the rather heavy amplifiers is a breeze (well, almost); there's no turning the box upside down, no re-tipping the amp back up etc. The box simply disassembles and collapses around its contents - or assembles around the product when packing it back up. If more heavy products were packaged in this manner, there would be a lot of reviewers around with healthier backs. This level of care goes some way towards establishing a buyer's sense of confidence in a product that reflects an overall philosophy of quality, extending from packaging to the product itself.

Enough about packaging. The CA-M400 amplifiers are an example of industrial design at its pinnacle. The aesthetics are simple and clean yet very elegant and the design theme is carried through to the company's numerous other products. The thick and solid natural aluminium fascia curvaceously bends around towards the rear at the sides without a wrinkle or blemish in sight -- this is quite difficult to achieve when thick aluminium is curved in such a manner --as it meets the extensive custom heat-sinking and solid steel chassis. A contrasting black-anodized aluminium control panel is off-centred and is host to the stand-by/on, mode and select buttons.

In conjunction, the mode and select buttons are used to control and configure the amplifier for either balanced or single-ended operation. They also manage the configuration for the turn-on delay or amplifier number (in multi-amplifier set-ups) for connection with a Classé preamplifier. The rear of the amplifier includes RCA single-ended and XLR balanced inputs which can be connected simultaneously and switched via RS-232 or the front panel. There's two sets of speaker outputs for bi-wiring and 3.5 mini-jack communication sockets in addition to the above-mentioned RS-232 connectors. The attention to detail even extends to the amplifier's feet which are substantial aluminium footers with a specialized rubber vibration-absorbing compound insert.

Each solid state Classé CA-M400 weighs 37kg and is rated at a powerful 400 watts RMS at 8 ohms and doubles-up to 800 watts into 4 ohms (not measured 20Hz-20Khz but at 1Khz). Voltage gain is 29.1dB and signal-to-noise ratio is a healthy 112dB. Oddly, input impedance – crucial for proper preamplifier matching – is not specified either on the website or the otherwise very informative instruction manual where mention is made of their easily-driven input stage.


Classé's designers chose to use a number of technologies where they thought they benefited the overall design most appropriately. The input stage uses J-FET devices that are utilized because of their high input impedance and low offset current. As a result, Classé amplifiers are easy to drive and exhibit low-noise, and the J-FET input stages don't necessitate the use of sound-degrading coupling capacitors. The driver and output stages use a combination of MOSFETs and bipolar devices so as to achieve what Classé's engineers consider the ideal balance for great sound. Each amplifier houses a massive custom toroidal transformer amongst other robust power supply componentry. The CA-M400s also incorporate extensive self protection against DC voltage, overheating and all other manner of potential mishaps.


Befitting Classé's philosophy, many of the above design decisions were arrived at after extensive subjective listening tests backed by comprehensive laboratory-bench measurements.