A high performance power amplifier is somewhat like a gourmet meal. The selection of individual ingredients, or electronic components in the case of an amplifier, is every bit as important as how they are combined together and laid out. The sonic performance of a power amplifier must meet the stringent demands of an audiophile, much like a meal must satisfy the taste buds of a food critic. Visual presentation is also quite important in both cases. Of course, unlike a gourmet meal, amplifier design also requires a little engineering wisdom.
The Canadian-made Classé Audio CA-2100 is the company’s entry-level power amplifier, although at $5000 it’s hardly an entry-level product at all. The choice of cuisine, if you will, for the Classé line-up of amplifiers is solid state, utilizing a combination of the best attributes from both class A/B and class A designs. Classé Audio says that this design was chosen, to eliminate the effects of switching distortion associated with class A/B designs and to avoid heat generation of a pure class A approach. The CA-2100 is designed to output 100 watts when driving 8 ohm speakers (with a THD of 0.003 percent), or 200 watts when paired with 4 ohm loads (with a THD of 0.005 percent).
Classé took a creative approach when designing their amplifier line-up, utilizing a variety of solid state devices, each chosen for its unique strength. For example, J-FET devices are utilized in the input stage chosen for their high input impedance and low offset current. The driver stage uses MOSFET devices because they are able to deliver the necessary voltage gain and are capable of meeting the current requirements of the output stage. Finally, bipolars were chosen for the output stage since they can deliver superior low frequency performance as well as stability.
The power supplies inside the CA-2100 use custom designed toroidal transformers and are protected by large surge resistors in series, from a potentially harmful current when the amplifier is powered on.
The chassis of the CA-2100 is constructed from a combination of steel and aluminium. At 47 pounds, the CA-2100 weighs a tad more than your typical gourmet plate, or an average surround receiver for that matter. Just to be safe, I “lifted with my knees” when moving it around. Of course, there’s a good reason why this amplifier is this solid and heavy. Its substantial weight goes a long way to controlling unwanted resonance caused by the sound system itself. The amplifier’s feet, made out of a special Navcom LimbSaver material, provide the proper stiffness and help to reduce external vibration. Two massive heat sinks on both sides of the amplifier assist with heat dissipation. The CA-2100 does not contain any fans and as a result runs dead quiet.
Visually, the CA-2100 looks like a high-end appliance rather than a meal. The rounded corners of the chassis, together with the silver and black finish, give this amplifier a very elegant and unique appearance. The front of the chassis contains Standby, Select and Mode buttons. Also present in the front are four blue LEDs that indicate which mode each channel is in, balanced or single-ended. The back of the chassis contains two sets of connections, balanced (XLR) and single-ended (RCA). Unlike other designs, all Classé amplifiers allow both connection types to be used at the same time. For example, the single-ended inputs can be used for a home theatre controller and the balanced inputs for an audiophile preamplifier. The back of the amplifier also contains two sets of five-way speaker terminals which can accommodate the bi-wiring of speakers. Other connections include a DC trigger input and output, an IR input and output, an RS-232 control port and a pair of RJ-45 connectors – all of these connections allow for integration with universal remote controls and multi-zone setups.
To start things off, I paired the Classé Audio CA-2100 amplifier with an Audio Research SP9-MKIII pre-amplifier and the Accentus A-104SE speakers (reviewed in our Mar/Apr 2007 issue). My audio sources included a Systemdek turntable and an Arcam DiVA CD73 CD player. Over the course of the first couple of weeks, I listened to a wide variety of music on this system, allowing the CA-2100 to settle in. I did notice immediately though, that the CA-2100 produced a smooth and refined sound. It added a certain magic of fullness and harmonics, with just the right amount of authority to this music system. I previously ran this system with a custom-built 30 watt per channel, class A/B amplifier which certainly lacked in both the bass and the dynamics departments – differences that the CA-2100 made very clear. It didn’t take me long to realize that this amplifier improved almost all the musical qualities of this system.
The CA-2100 reproduced every little nuance of micro dynamics in the music that I listened to. My listening selection played with the fluidness of small single-ended tube amplifiers but at the same time with the authority and control of a great big solid-state power amplifier – an amplifier that never runs out of power or changes its musical character. The CA-2100 offered lots of clean power, there was no question about it. It provided a deep bass extension, with a controlled punch and weight when required. Whatever the CA-2100’s power limit may be, I certainly never reached it, nor did I ever feel the need to listen to it overly loud to appreciate the music, thanks to its incredibly low noise floor.
During my more in-depth listening session, I started with a familiar selection including Sade’s Stronger Than Pride LP, The Best of Sade CD and Radiohead’s OK Computer (on both CD and vinyl). The airy sound of Sade’s vocals floated in my room like the softest of feathers in the wind and tickled my eardrums. Her voice filled my room with the naturalness that was impossible not to love. High frequencies were superbly detailed, yet never at all bright. The subtlest musical gestures remained in perfect scale thanks to the CA-2100’s solid-state architecture. Details, like the dimensions of the reverb, were balanced and accurate. The CA-2100 was capable of producing a phenomenal amount of detail without ever fatiguing my ears, even during extended listening sessions. Closing my eyes and getting lost in the music came naturally with this amplifier. While many solid state amplifier designs can produce detailed sound, they can also make your ears tired quickly. I’m glad to say that this was definitely not the case with the CA-2100 – its sweet character was simply irresistible.
When I placed The Best of Blondie 80s LP on the platter, I instantly heard more dimension to every part of the music, compared to the CD version of this album. The seamless integration from the top to the bottom frequencies was accompanied by an exceptional sense of timing. The bass line was perfectly timed with the cymbal. I never felt that there was a lack of congruency between the various sounds on this album.
The harmonics of various instruments came across full bodied and natural. They were not the artificial harmonic content that some amplifiers introduce – these harmonics were positively the real thing. The soundstage and imaging of the CA-2100 were also exceptional, surely thanks in part to its super low noise floor. They provided a great width and depth to the sonic landscape, especially with well-recorded material.
The Classé Audio CA-2100 served up sonic pleasure to my ears like a celebrity chef serves up a gourmet meal – with passion that’s hard to forget. It is a fantastic power amplifier that has a natural sonic character, capable of turning every type of music into a passionate experience. If you’re looking for a power amplifier within the $5000 price range, you will definitely want to take a listen to the CA-2100. I must admit that this amplifier left me wondering one thing – how do the more expensive Classé Audio components sound? After all, the CA-2100 is only their “entry-level” model.
$5000.00 MSRP (CAD)
Classé Audio CA-2100 Power Amplifier Review
• Power/channel (continuous): 100W (8 ohms), 200W (4 ohms)
• Voltage gain: 29.1dB
• Bandwidth:155kHz (-3dB), 22kHz (-0.1dB), phase < -10° (22kHz)
• Sensitivity: 1.0Vrms
• THD + noise (unweighted, 10Hz – 500kHz bandwidth, 0.8Vrms/1kHz input): 0.003% (8 ohms), 0.005% (4 ohms)
• Dimensions (LxWxH): 419 mm x 445 mm x 121 mm (16.5” x 17.5” x 4.75”)
• Weight: 21 kg (47 lbs)