Усилители мощности моно — Line Magnetic AS-128

The AS-128 is a Class A single-ended monoblock tube amplifier from Line Magnetic in its Analog Sound series, with one 212 transmitting triode as the output valve in each chassis. Every unit includes a real built-in preamplification stage, and a front panel switch changes its role between power amplifier and integrated amplifier. The amplifiers are supplied as a mono pair.

Key specs that matter

Rated output is 30W RMS per unit, delivered in Single-Ended-Triode Class A. Frequency response extends from 10Hz to 45kHz within 2dB, total harmonic distortion is 1% with 88dB signal-to-noise. Sensitivity is 500mV, input impedance is selectable between 100k ohms and 600 ohms, and gain can be set to 40 or 52dB with a front selector. Output impedance options are 4, 8 and 16 ohms. Each chassis measures 490 x 400 x 600mm and weighs 70kg. Power consumption is 1.4A from a 220V mains supply at 50Hz with a tolerance of 5 percent.

Engineering and use context

Six valves are fitted per channel - two 12AX7, one 6L6, the 212 output triode and two 5U4G rectifiers. With a single 212 working single-ended, the output stage stays in Class A. Every connection inside is hand-wired point-to-point. Signal enters the preamplifier stage of each mono unit through a Western Electric 618 replica input transformer. The front meter display has its own on and off toggle. Line Magnetic lists the AS-128 alongside the push-pull AS-125PP, the AS-125 stereo integrated model and the AS-123 buffer in its Analog Sound family. The high and low voltage stages draw from separate dual power inputs.

Pairing

Each unit offers four RCA inputs, and loudspeakers connect to screw terminals that also accept banana plugs. The amplifier is made in China. Crated for shipping, each chassis comes to around 100kg. Accessories in the box are a remote handset, a detachable mains cord and a pair of spare fuses. In North America the pair was priced at USD 38,000, while the Australian listing started from AUD 40,500 in a grey finish, with the units configured for 240V mains.

Alternatives

Line Magnetic also builds the AS-125PP, a push-pull Class AB monoblock that uses a pair of 211 triodes to reach a rated 60W.