Усилители мощности стерео — Msb Technology The S202 Stereo Amplifier

The S202 is the compact stereo power amplifier from MSB Technology of California, a fully modular design with a matched impedance input stage and an all-billet CNC case. The M205 monoblock uses the same case size, whereas the S202 carries both channels on a single custom low-noise toroidal transformer.

Key specs that matter

Continuous output is 200 W per channel into 8 ohm and 380 W into 4 ohm, both at less than 1 percent distortion. Gain measures 23.8 dB with a 150 ohm source. Frequency response holds within 0.03 dB from 20 Hz to 20 kHz, signal to noise is above 130 dB (133 dBA), crosstalk at 2 kHz is below -110 dB and equivalent input noise is 0.65 microvolt in a 22 kHz band. Output impedance is 0.01 ohm. Two balanced XLR inputs have a switchable impedance of 75, 300 or 1,200 ohm, and one binding post set serves each channel. Static power draw is 90 W, and the unit runs from mains through a 10 A slow-blow fuse. The case is 404 mm wide, 483 mm deep and 165 mm high, or 178 mm with feet, and weighs 41 kg.

Engineering and use context

MSB builds the input stage as a discrete Class-A circuit, followed by high-current output buffers. The billet aluminium chassis takes 14 hours of CNC machining and provides about 1.9 m2 of heatsink area per amplifier, with high-power heat pipes moving heat to the fins. Soft-start circuits and power-on timers control switch-on. Controls include an input impedance switch, on and standby buttons, a display dimmer and a 12V mode switch next to two MSB trigger ports, so the amplifier can follow a source or preamplifier into standby, and the same functions are available through push buttons and remote commands. Several ground posts are provided on the rear panel to reduce electromagnetic interference. The mains input accepts 120 or 240 V with automatic switching, with a fixed 100 V version for Japan-style supplies. Owners can pick a matte silver or matte black anodised case and fit M6X1 audiophile feet.

Pairing

Two XLR inputs make it simple to connect a balanced line stage or an MSB converter that handles level itself, and the selectable input impedance lets the owner match the load to the source. The low output impedance points to firm control of conventional passive speakers.

Alternatives

The MSB S500 Stereo Amplifier is the bigger two-channel model, adding a 1.0 Farad power core and three gain settings.