WHEN THE LEXUS LS400 was first introduced in 1992 it was lauded immediately, not because of its looks or engineering, but more for its amazing absence of extraneous noise and the quality of its audio system. It was, said its many admirers, the nearest to concert-hall reproduction on the move that any car could offer. That it was merely a luxury car modelled closely on a Mercedes-Benz or BMW caused many to shrug and declare Lexus would never challenge the Germans, but as far as the sound system was concerned, this was in a class of its own. The LS400 was succeeded by the LS430, at first glance only a facelift model, but one to which a huge amount of technical resources had been applied. It was lighter, more powerful and more comfortable. And it still offered that wonderful, silent ride: low wind noise, no engine boom and little in the way of road interference. The only way Toyota engineers could surpass the sound quality of the LS430 was to introduce a premium audio system, which now, thankfully, they have done. The latest LS430 - the car Financial Secretary Antony Leung Kam-chung bought before he raised car taxes in this month's Budget and which now costs $839,100 at Crown Motors (tel: 2511 9430) - now features a Mark Levinson stereo which comfortably surpasses anything fitted to any other passenger vehicle. It is without peer. The sound quality of the American custom-built system is as good as the best, high-end home stereos, with a six-disc CD auto-changer, tuner and cassette deck, playing through no fewer than 11 strategically placed speakers. The system is the best there is. To sit in the (individually electrically operated) rear seats and listen to the concert effect of say, a Beethoven piano concerto or a Bach cello suite is a magical experience. Toyota engineers can be proud of the LS430's interior too. Bird's eye, walnut-wood panelling; full leather upholstery; four power seats (the ones in the back would be a perfect setting for Baby Leung) - the driver's with three memory settings; a power-adjusted steering column with an auto-away easy entry system; a massage function within the rear seats and a power rear window blind all contribute to an immense sense of well-being. And the silence of the LS430's drive is amazing: a drag coefficient of just 0.25 - the lowest of any passenger saloon car - ensures that little or no wind noise is created. Performance and straight-line stability are also aided by this aerodynamic efficiency, as of course is fuel consumption. In the rear there are separate controls mounted in the centre console for the air-conditioner, rear blind, heating and massage functions as well as that magnificent sound system. The power unit of the latest Lexus is a lightweight 4.3-litre V8 with variable valve timing, developing a healthy 278-brake horsepower (207kW) at 5,600rpm, while the strong torque output peaks at 417Nm at the reasonably low engine speed of 3,500rpm. The high-torque V8 is mated to an electronic automatic transmission which offers almost seamless shifts, with response further enhanced by the car's electronic throttle-control system which controls the accelerator based on pedal position, vehicle speed and engine revs. New electronically controlled air suspension maintains a constant ride height, while also adjusting the dampers in response to various driving conditions. There are two height settings: high or normal; the former for rough roads, although the system returns to the latter mode at 80km/h, while over 100km/h on a flat road it will lower the car by 20mm for increased stability. The LS430 has lots of safety, with dual front airbags, side airbags and four window airbags to protect front and rear occupants from flying glass. The front seats also incorporate a whiplash-injury lessening system with pre-tensioners and force limiters on the belts. All seats are equipped with three-point seat belts. The front airbags deploy an advanced sensor for two-stage inflation depending on the severity of the impact, while a passenger sensor disengages the passenger-side airbag if the seat is not occupied. Additional safety features include automatic rain-sensing wipers as well as water-repellent windscreen glass, automatic headlamps, a vehicle-stability system and traction control. Other novel features include an automatic boot-lid closer, along with a similar arrangement for the doors. There is also a smart-key system which unlocks the doors, operates the ignition and will even close the windows remotely. As you would expect in a car of this calibre, the top-of-the-range Lexus has a top-class automatic climate-control system, with an active charcoal filter and separate left and right controls. But this system differs in an independent swing facility which will detect if there is a passenger in the front seat. If the seat is vacant, it automatically directs the air flow towards the driver. Clever. The latest Lexus is a superb luxury car, but its glory must be that sound system. But words cannot really convey its quality: sit in the back of the LS430, even in the showroom, put on some fine music and enjoy. It beats anything the opposition can offer by a very long way.