Усилители мощности стерео — Cary Audio CAD-120S MKII

The Cary Audio CAD-120S MkII is a fully balanced stereo vacuum tube power amplifier with a Class AB push-pull output stage. Its factory list price is USD 6,995, and it belongs to the current Cary range of tube power amplifiers, alongside the CAD-805RS and CAD-211FE. The chassis is anthracite black, while buyers choose a silver or black aluminium faceplate.

Key specs that matter

Output is 120 W per channel in Ultralinear mode or 60 W per channel in Triode mode. Frequency response is 17 Hz to 25 kHz measured at 1 W, noise and hum are rated at -80 dB, input sensitivity is 1.24 V and gain is 28 dB. Both the XLR and RCA inputs present an input impedance of 100 kohm. The amplifier measures 203 mm high, 432 mm wide and 356 mm deep and weighs 29.5 kg.

Engineering and use context

The tube complement comprises two 6SN7 double triodes in the input gain stage, two more 6SN7 as drivers and eight KT88 output tubes, four per channel in push-pull. A front panel selector switches the output tubes between Ultralinear and Triode connection, and Cary describes the lower power setting as Class A operation, with Class AB used at the higher rating. The fully balanced topology carries the signal differentially from input to output, and the choice of XLR or RCA connection means both balanced and single-ended preamplifiers can drive it. The input circuit uses 1% precision metal resistors and Kimber capacitors. The supply section uses an EI high voltage and bias supply transformer and four 560 uF capacitors, and it runs on 117 or 234 VAC at 50 or 60 Hz. Each channel has a special bifilar wound output transformer rated at 150 W, and loudspeakers connect to gold plated copper five-way binding posts. The maker quotes a warm-up time of 3 minutes after switch-on and a break-in period of 100 hours before the amplifier reaches its intended performance.

Pairing

A preamplifier with balanced outputs can make use of the differential input stage, while one with only RCA outputs can still be connected directly. The input sensitivity should be compared with the output level of the chosen preamplifier or DAC with volume control to make sure full power can be reached. Cary offers the SLP-05 and SLP-98 tube preamplifiers in the same catalogue, and the SLP-98 adds a phono stage. The MA-300 analog bias meter is listed among Cary accessories.

Alternatives

The Cary Audio SA-200.2 ES is a transistor stereo power amplifier listed in the current Cary catalogue.