Luxman L-507sII (1999–2001)

Name: Luxman L-507sII
Brand: Luxman

The L-507sII is an integrated amplifier from the post-Alpine re-launch, when production was handled by AZDEN. It arrived in January 1999 at ¥280,000 as a refined version of the L-507s (1996), using the circuit technology and parts of the larger L-509s. The sII update was made for SACD-era bandwidth compatibility, and the line would run until 2001. As one source puts it, this was the last period of real worldwide visibility for Luxman, with much smaller lineups and shrinking distribution.

It's a heavy amp with serious specs: 110W + 110W into 8Ω, total harmonic distortion of 0.005% or less at rated output (1kHz, line straight), and a frequency response out to 100kHz on line inputs. It weighs 18.3kg and measures 467 x 179 x 418mm. The amplifier section uses Pc150W-class large-capacity transistors. Luxman's own OD β (Optimized Dual βeta) circuit technology is at the core, alongside a CSSC (Complementary Single Stagger Circuit) design. A large EI-core power transformer handles the supply. The microcomputer that runs the remote control gets its own dedicated transformer, kept fully separate from the audio circuit to prevent noise.

There are four line inputs and two XLR balanced inputs. The phono stage switches between MM and MC (2.0mV/47kΩ for MM, 0.25mV/100Ω for MC). Main-in and pre-out let you use the pre and power sections independently. There's also a line phase sensor for AC polarity management, two backlit logarithmic meters, a motor-driven input selector and volume control, and a wireless remote. The front panel got Luxman's special pear finish, with a thick aluminum plate behind the indicator section.

Surviving documentation is thin. No professional reviews in the period press turned up, and much of what circulates today comes from seller listings. Those listings consistently say units were bought at auction in Japan, serviced, and often switched to 220V operation. Russian sellers describe it as "a legend with a capital L," and one notes the wooden cabinet side panels, which the sII added to enhance the luxurious feel. The phono stage is worth a mention: unlike the C-7 and M-7 separates of the same period, the L-507sII has a proper MM/MC stage built in.

The record is also tangled because listings often conflate the L-507s and L-507sII. The original s model made 100W per channel and weighed 20kg per thevintageknob.org. The sII, per audio-database.com, makes 110W and weighs 18.3kg. Confirm which version a given unit is. A service manual is indexed on eserviceinfo.com, and forum threads show owners seeking it, but no full manual content has surfaced.