Усилители мощности моно — Mark Levinson № 631

The № 631 is a monaural power amplifier in the 600 Series from the Harman group's Mark Levinson marque. The series was unveiled at High End Munich in 2025 together with the № 626 preamplifier and the № 632 stereo amplifier, with deliveries planned from the fourth quarter of 2025. Each № 631 is priced at USD 40,000, GBP 37,999 or EUR 43,999, so a stereo pair needs two units. It is designed, built and assembled in the USA.

Key specs that matter

The chassis stands 522.7 mm tall, 305 mm wide and 521.9 mm deep, a floorstanding tower rather than a rack component, and it weighs more than 60 kg. Inputs per unit are a single XLR socket and a single RCA socket, while two pairs of Hurricane binding posts allow bi-wiring. Control connections are two 3.5 mm trigger jacks for 3 to 12 V DC, one in and one out, a USB-A port for service and an RS-232 port.

Engineering and use context

The circuit follows the Pure Path approach, fully differential and fully discrete with no integrated circuits or op-amps from input to output. Operation is Class A/AB, and a selectable high-bias mode keeps the output stage in Class A over a wider range. Mark Levinson explains that a very high bias current lets the design reach low distortion and wide bandwidth with very little feedback, and makes it less sensitive to parasitic capacitances. Power comes from a custom ultra-low-noise toroidal transformer mounted in the centre of the chassis and structurally isolated, housed in its own module inside the modular construction. The analogue circuit boards are rubber-mounted, and the feet are shaped to damp vibration from the floor. The housing is machined from solid aluminium anodised black on a silver plinth, with sculpted heat sinks forming the side panels, a ventilated top and a glass centre panel lit in the red accent colour of the Tectonic Industrial Design, which draws on earlier Mark Levinson styling while adding new lighting and glass elements.

Pairing

The matching partner is the № 626 dual-mono preamplifier, whose balanced outputs suit the XLR input of each monoblock, and the triggers let the preamplifier switch both units on together. A pair of towers needs floor space beside the equipment rack rather than a shelf.

Alternatives

The Mark Levinson № 536 is an earlier monaural amplifier rated at 400 W into 8 ohms and 800 W into 4 ohms with stability into 2 ohms.