That's the theory, now for the practice, as witnessed in Sony's Tokyo labs on a high-end HDTV Trinitron. Initially, the most striking thing about the Blu-Ray recorder is its bulk - it weighs a hefty 14kg. Nonetheless, its imposing looks befit the £2,000 price tag. First off, we used the integral digital satellite tuner to find a suitable HDTV broadcast, in this case from NHK, which is Japan's equivalent of the BBC.

Slightly daunted by the staggering quality of the broadcast, we slotted in a caddy-protected Blu-Ray disc and recorded a few minutes at the highest bit-rate, which allows for around two hours of full-quality HDTV with Dolby 5.1 audio. Playback was literally perfect, with no quality loss whatsoever - which is a truly impressive result. Dropping down through the stepped recording levels, we repeated the feat at the lowest permissible quality, which squeezes 12 hours on to a disc.

At this level, the reach-out-andtouch quality of full HDTV was gone, with slight picture noise but a still excellent DVD-standard recording. The recording mode must be set manually, although it might have been an option for Sony to allow the machine to consult its electronic programme guide (EPG) and automatically work out how best to fit in the show you're recording.

For such a seemingly complex machine, the BDZ-S77 is actually a breeze to operate. The majority of functions can be accessed through a joystick on the foot-long remote handset, while those that can't are hidden under slider panels. The onscreen menu is Sony-slick and even provides indexing data for each recording on a disc. Recording is non-linear, via DVD-RAM or a hard drivebased recorder, which allows for simultaneous playback and recording and more efficient use of disc space.

Recordings can only be made on a Blu-Ray disc, but the machine can play any DVD, DVD-R/RW, CD, CD-R/RW or CD-DA. We played back a DVD and can report that the output was similar to HDTV recorded on the unit's long-play mode. Audio buffs are well catered for, with analogue, coax and optical digital outputs included. As you would expect at the price, composite, component and S-Video outputs are all present and correct.

Overall, if you're both in Japan and into HDTV in a big way, then the BDZ-S77 is a compelling option. It is expensive, and bear in mind that you'll need a digital satellite dish to secure something for the onboard tuner to decode, as well as an HDTV-capable display. Considering suitable TVs start at around £3,000 in Japan, you're looking at the thick end of five grand to get this impressive AV show on the road.