Интегральные усилители — Line Magnetic AS-125PP 211

The AS-125PP 211 is a mono integrated valve amplifier in Line Magnetic's Analog Sound range, sold in pairs so that each channel gets its own chassis. Where the AS-125 uses a single 211 per side in Class A, this model places two 211 triodes in a push-pull output stage and runs them in Class AB. Each unit keeps a full preamplifier stage, so a pair can take sources directly.

Key specs that matter

Output is 60 W RMS per monoblock, quoted by the maker as 60 W + 60 W for the pair. The frequency response extends from 10 Hz to 70 kHz within 2 dB. The maker quotes 88 dB for signal to noise and 1 percent for THD. Two sensitivity values are given, 500 mV and 14 mV, together with input impedances of 100 kohm and 600 ohm, and the gain control switches between 51 and 63 dB. Each chassis has four pairs of RCA inputs and speaker taps for 4, 8 and 16 ohm. One unit measures 480 x 275 x 490 mm and weighs 43 kg, and a crated pair comes to about 70 kg. The maker's data lists 220 V mains with a draw of 1.4 A, while units for Australia are set for 240 V.

Engineering and use context

The valve complement of each monoblock is one 12AX7 and two 12AU7 small-signal types, two 6V6 (6P6P) drivers and the pair of 211 output triodes. A Line Magnetic replica of the Western Electric Model 618 transformer feeds the input of the preamplifier stage. All parts are joined by hand-laid point-to-point leads rather than traces on a board. The high-voltage and low-voltage stages each receive their own separate power input. A VU meter on the front panel can be switched on or off. The chassis dimensions are identical to those of the stereo AS-125, so the two models share one enclosure format, although the circuits inside them are different.

Pairing

With its push-pull output stage, the AS-125PP 211 has considerably more power on tap than the single-ended AS-125, so it is less restricted to high-efficiency horn designs. Line Magnetic's LM-812 horn system is an 8 ohm design rated at 102 dB, but its 40 W power limit sits below the amplifier's output, so the volume has to respect that rating when the two are combined. Owners who already have a separate preamplifier can use a front panel switch on each monoblock to change it to power amplifier mode and bypass the internal volume stage.

Alternatives

The Line Magnetic AS-128 212 is a Class A mono integrated amplifier that uses one 212 triode per chassis for 30 W RMS.