Усилители мощности стерео — Kora CSA 270

The CSA 270 is a stereo Class A power amp made by Kora, the French brand revived in 2017 by engineer Bruno Vander Elst after the original company, founded in 1990, had closed in the early 2000s. Production is in the Toulouse area. Before 2025 the relaunched range consisted of the TB140, TB200 and TB400 integrated amplifiers, the TA240 and TA480 stereo power amplifiers operating in Class AB, the PR140 preamplifier, the CD140 player, the DAC140 converter and a phono stage. The CSA 270 opened a new pure Class A series, shown for the first time at the Munich show in May 2025 together with the CSA 1150, CSA 2120 and CSA 1200. It is the smallest stereo model of that series. The French launch price was EUR 19,800, and in the United States it sells for USD 24,999 and is built to order.

Key specs that matter

Output is 2 x 70 W into 8 ohm in pure Class A. Both channels offer an RCA socket and an XLR socket. The power supply is linear, with a bank of capacitors totalling 400,000 µF. The case is 420 x 440 x 260 mm (width, depth, height), made of aluminium and steel in a Mineral grey finish, and the amplifier weighs 32 kg. The same chassis is also sold as the CSA 1150 monoblock rated at 150 W.

Engineering and use context

Kora describes Square Tube as a valve operational amplifier. Four valves, two ECC82 and two ECC83, handle the voltage side of the signal, while solid-state output devices provide the current. Vander Elst developed the circuit, and it is used across every current Kora amplifier. A Class A stage keeps its output devices conducting at full bias all the time, which is why it draws most power at idle and needs large heat sinks. To limit that consumption, the CSA series uses adaptive current management - a high-current and a low-current mode, selected manually or automatically, with the low mode used when the loudspeaker impedance permits while operation into the rated load stays in pure Class A. Signal detection turns the amplifier on when music starts and puts it to sleep when the input goes quiet.

Pairing

As a power amplifier without volume control, the CSA 270 has to follow a preamplifier, or a DAC or streamer with its own level control, and the PR140 is Kora's matching preamplifier. The XLR inputs accept balanced preamplifiers. Given its moderate Class A output, it is best matched to passive loudspeakers of average or better efficiency and an easy nominal load.

Alternatives

The Kora CSA 2120 is the stereo model with 2 x 120 W in Class A, a 560,000 µF capacitor bank and a 660 mm deep case, priced at EUR 28,200.