ClasseSigma Amp2Classe Sigma Amp2 2 CHANNEL AMPSigma AMP2 TWO-CHANNEL AMPLIFIER The Sigma series AMP2 is a 200W/Ch stereo amplifier utilizing switching technologies for both power supply and amplification stages. A Classé-designed switch mode ...2400.00

Classe Sigma Amp2 2 CHANNEL AMP [Expired]

no longer for sale


The Sigma series AMP2 is a 200W/Ch stereo amplifier utilizing switching technologies for both power supply and amplification stages. A Classé-designed switch mode power supply with Power Factor Correction makes over 1,000W of clean and stable power available while being both compact and efficient. A new class D amplifier topology provides wide dynamic range, smooth and extended frequency response and rich harmonic detail to yield stunning sonic performance. The efficiency of class D adds efficiency, low heat dissipation and relatively small size to the list of the AMP2’s attributes.

Sigma series amplifiers are designed to pack tremendous power, performance and value into relatively small and energy efficient chassis. The Sigma series AMP2 is derived directly from the acclaimed Delta series CA-D200, sharing both power supply and amplifier circuitry. In the same way that our CT series models use the same circuitry as the equivalent

the AMP2 is actually the 200W/Ch CA-D200 in a Sigma series chassis. The AMP5 also shares these same power supply and amplifier topologies, but with the necessary changes implemented to accommodate its five-channel configuration.

The basis of the design is switching technologies, used
in both the power supply and audio stages. A Classé- designed Switch Mode Power Supply (SMPS) and Power Factor Correction (PFC) circuit, each operating at over 90% efficiency, provides a crystal clear reservoir of over 1kW of power. The low frequency dynamics, extension and control of these amplifiers and their ability to effort- lessly drive difficult speaker loads can be credited in large part to the powerful and sophisticated power supply they employ. This combination of SMPS with PFC allows the Sigma series amplifiers to draw current from the wall throughout the voltage cycle, avoiding the sharp spikes

of current drawn by conventional power supplies. Such sharp and short current demands cause high-frequency harmonics on the AC mains. By creating no such distur- bance, the Sigma series amplifiers deliver their prodigious power while remaining effectively silent as far as the AC shared with preamp/processor and source components

AMP2 and AMP5 audio circuits use a true digital archi- tecture, taking advantage of DSP to solve an issue called dead-band-time, the greatest source of distortion in oth- erwise well-designed class D amplifiers. Dead-band-time, somewhat analogous to switching distortion in a class A/B amplifier, is the time when the plus and minus halves
of the amplifier are both off; it should be as close to
zero as possible and i design it is less series amplifiers use only a small level of overall negative feedback, helping to achieve low intermodulation distor- tion. Proprietary driver stage FETs ensure quick

and precise switching of the output stage, contributing to the amplifiers’ vanishingly low dead-band-time and maximizing their efficiency. The critical output stage filters are then used to filter only the 384 kHz switching frequency, leaving the amplifier with a neutral, extended and open upper midrange and high-frequency performance.

The Sigma AMP2 and AMP5 owe their outstanding performance and value to the unique engineering and manufacturing capabilities of Classé in Montréal and the B&W Group globally. No other high-end audio designers have access to the resources necessary to deliver such amplifiers at such competitive prices. The AMP2 and AMP5 have been conceived and built as examples of quality and value without peer. They will stand as bench- marks in the advancement of class D amplifier technology.

All tests un-weighted and 20Hz – 20kHz measurement bandwidth used.

Frequency response


10Hz – 20kHz, -1dB into 4Ω

Output power


200W rms into 8Ω 400W rms into 4Ω

Harmonic Distortion


<0.018% @ 1kHz Balanced Input

Peak Output Voltage


116V peak to peak, 41V RMS no load
116V peak to peak, 41V RMS into 8Ω

Input Impedance


100kΩ Balanced / 50kΩ SE

Voltage gain


29 dB

Input level at clipping


1.4Vrms Balanced/SE



>80 dB below fundamental into 8Ω Balanced

Signal to Noise Ratio


-100 dB at peak output into 8Ω (AES17)

Rated power


177W @ 1/8th power into 4Ω

Mains voltage


100V - 240V, 50/60Hz

Overall Dimensions


Width: 17.00" (433mm)
Depth (excluding connectors): 14.57" (370mm)
Height: 3.75" (95mm)

Net weight


22.0 lb (9.97 kg)

Shipping weight


28.0 lb (12.70 kg)