Интегральные усилители — Line Magnetic LM-212 Premium

The LM-212 Premium is a two-channel integrated amplifier from the Chinese tube specialist Line Magnetic Audio, built around the 212 transmitting triode in a single-ended triode layout. Reaching that power level from one 212 per side is uncommon, and Line Magnetic says it re-engineered the demanding 212 tube for safe and stable use in a home system. The amplifier uses a split-chassis construction, with the amplification circuits in one enclosure and the power supplies in separate units.

Key specs that matter

Rated power is 50 W plus 50 W in single-ended Class A, taken from 4, 8 and 16 ohm taps. Each channel runs one 212 output triode, with a KT88 as driver and a 12AX7 in the input stage, six tubes in all. The maker quotes a range of 20 Hz to 35 kHz, 86 dB of signal-to-noise and an input impedance of 100 kohm. Distortion is rated at 1% at 1 kHz. Line input sensitivity is 160 mV, and the pre-in socket needs 500 mV. Residual background noise is below 1 mV.

Engineering and use context

Power supply design is where the split chassis matters. Four Z11-core transformers are specially wound for the LM-212 Premium - two for the high voltage rails, one for the low voltage circuits and one reserved for the filaments of the 212 tubes. The amplifier unit alone weighs 66 kg, and the power supply section comes as two units of 39 kg each, 78 kg together, so the complete amplifier weighs 144 kg. The overall dimensions are 500 mm wide, 610 mm high and 555 mm deep. Consumption from the wall is listed at 720 W to 750 W, and the Australian version is wired for 240 V. Inputs are three RCA line connections plus one RCA pre-in, which lets an external preamplifier feed the power stage directly while bypassing the internal volume stage. The European list price is EUR 24,000. Held to a tolerance of plus or minus 1 dB, the response ends at 25 kHz, a tighter window than the headline range.

Pairing

A system built around this amplifier can stay within the brand. Line Magnetic makes horn loudspeakers based on Western Electric designs, such as the LM-3, whose nominal impedance lines up with the highest output tap of the LM-212 Premium, and the company also makes a separate tube preamplifier, the AS-133 with 2A3 triodes, that can drive the pre-in socket.

Alternatives

The Line Magnetic LM-300IA is a smaller single-ended integrated amplifier using 300B output tubes and giving 10 W per channel.