Интегральные усилители — Line Magnetic LM-126

The LM-126 is a stereo valve integrated amplifier that Line Magnetic built to mark its tenth anniversary, and the maker files it in its Analog series next to the AS-128 and AS-125PP monoblocks. The company was set up in 2005 by two brothers and started out repairing and replicating Western Electric, Altec and Jensen equipment, and the LM-126 follows that background by taking a Western Electric amplifier circuit as its blueprint. Line Magnetic describes its approach as keeping such proven historic schematics and building them with modern high-grade parts. Instead of the 6L6 output valves of the original concept, it uses the KT66 to raise output for present-day loudspeakers.

Key specs that matter

The rated power is 15 W plus 15 W RMS, delivered from speaker taps for 4, 8 and 16 ohm loads. The output stage uses four KT66 valves, and rectification is handled by 5U4 valves. Line Magnetic specifies a sensitivity of 500 mV, two input impedance values of 100 kohm and 600 ohm, and gain that can be set to 40 or 52 dB. The frequency range extends from 10 Hz to 45 kHz within plus or minus 2 dB, with 88 dB signal to noise ratio and 1 percent total harmonic distortion. The chassis measures 480 x 300 x 530 mm and weighs 42 kg, and current draw is 0.8 A from a 220 V supply, with 110 V and 220 V versions listed at a tolerance of 5 percent and 50 Hz.

Engineering and use context

At the front of the circuit sits a copy of the Western Electric 618 input transformer, the same transformer family the brand uses in its heavier Analog monoblocks. The power supply rectifies the high and low voltages separately and filters them through two choke coils. The maker describes the model as an integrated or power amplifier, so it can take a signal either through its own volume stage or from a separate preamplifier. Line Magnetic states that all of its electronics are hand-wired point to point inside, and this anniversary model is assembled the same way.

Pairing

The modest KT66 output is best matched with efficient loudspeakers, and the highest tap gives a direct match for high-impedance loudspeakers, while lower-impedance designs have their own terminals. The higher gain position gives extra headroom when a source has low output, and the lower position suits players and streamers with a stronger line signal.

Alternatives

The LM-216IA Plus is a smaller stereo integrated amplifier from the brand, using push-pull KT88 valves rated at 45 W per channel.