'Specifications', to me, is a euphemism in audio for 'license to tell whopping great lies'. But one number will tell you more about Theta's Casablanca than all the ad copy the company can muster: 41. That's the number of pages in the owner's manual, and you'll have to read at least 30 of 'em before you're fit to operate one of the most comprehensive, facility-laden devices since that classic 600-series Nakamichi pre-amp of yore. When a pre-amp occupies a space of 19x16x7.5in and weighs 43lb (specs, I know, but ones which can't be misinterpreted), it has to offer more than a massive case.

Especially when it costs £3998 just for the 'bare' chassis.

That's the key to the Casablanca: You can include or delete as many options as you like. Credit goes to Cello for pioneering this approach with the original Suite, but it's the computer era which has turned modularity into something less-rarified than studio practice. In the newest pre-amp/processors, you get what is more-or-less the PC-card approach to system building. The Casablanca, Krell's KAV and the forthcoming Meridian 800 series have built on PC architecture to create what we can only hope will be components even more resistant to obsolescence, by virtue of 'upgradeability', than the computers they emulate.

Right after the Hi-Fi Show, I borrowed the importer's well-worn, certainly burned-in Casablanca, one complete with just about every analogue, digital, and video option, including the superior (nearly Pro Gen Va) level D/A converter and a selection of phono and XLR inputs and outputs. The choices were bewildering: balanced or single-ended, coaxial or TOSlink, S-video or RCA-phono, PAL or NTSC.

I ended up treating the Casablanca as if it were a high-end audio pre-amp which just happens to preclude the need for an external DAC, surround processor, or video routing system. For optimum performance, I restricted my A/V use to the S-video connection of a Theta DATA III laserdisc transport with NTSC discs and both DTS and Dolby Digital software. Then I dropped the Casablanca straight into a system employing a separate pre-amp, processor, and D/A converter, immediately enjoying the benefits of the need for two fewer mains outlets and a bunch of interconnects. (No, I'm not about to start extolling the virtues of receivers over separates; the Casablanca is about convenience rather than compromise.)

It's apparent that Theta, unlike Meridian, wanted to make the Casablanca easy to use rather than to cloud its operation in arcane rituals. A big f'rinstance: The analogue-to-digital selector, which chooses between the analogue or digital sources which share input numbers, is marked - surprise! - 'A-D'. No hidden commands, no seeking the function in the small print of some unlikely menu. Another f'rinstance: Whatever button you might hit for a sub-menu (all of which appear on-screen) will get you back to the main menu if you press it again. And you find yourself surfing through the wrong menus until you get the hang of it. What's so reassuring about this simple approach to menu selection is that you needn't worry about fouling up the configuration settings which your installer spent an afternoon establishing with SPL meter and tuned ears. If, for example, you accidentally find yourself looking at the rather daunting menu for the output levels of your five subwoofers, set to the nearest decibel, you needn't run out of the room screaming. Just hit the set-up button one more time and you're back at the previous menu.

Not that Theta is unique in this regard; I found the Lexicon DC-1 - after a 15-minute briefing from the UK distributor - to offer a similarly logical approach, and even the cheapest A/V receivers feature diamond-shaped up/down/left/right combined playback level/balance controls. (Oh! for the joysticks of 4-channel receivers of days gone by!) What Theta did was isolate the minor, less-often required functions while providing prominence for the most common (source selection and mode, for example), teaching the machine to do the rest.

This was made clear after I spent ages trying to get DTS discs to deliver something other than silence. Had I read the manual first, I'd have known that the Theta has to re-align itself between Dolby Digital and DTS when you have one laserdisc player with two digital outputs: one for DTS and normal digital sources, the other an RF connection for Dolby Digital. I didn't realize that the Casablanca was clever enough to select between them automatically, probably because there was a good 15 second delay. I spent more time than I care to admit scrolling through menus...

Eventually, I ended up with the Theta routing signals to and from the aforementioned DATA III, a second CD transport from Marantz, a Panasonic hi-fi VCR and monitor, both NICAM-equipped. The Theta's output fed, at various times, a six-channel Marantz power amp or a couple of Acurus amps, one with three channels and the other with two. The only aspect of performance I didn't sample was its control over subwoofers, simply because my 14x22ft room is well-served by three Apogee LCRs across the front and a pair of Apogee Ribbon Monitors for the rear. I may be an American, but I share not my nation's thuggish passion for stomach-churning bass. And if eight 6in woofers ain't enough for that room, well, it'll have to be no more dinosaur movies for me, I suppose.

It took about two seconds to realise that here was - beyond any doubt - a bridge between audiophilic concerns and home cinema, precisely the kind of product which makes the us-vs.-them schism seem truly ludicrous. Please do this one thing: forget the sound of sub-£1000, all-in-one-including-amplification, 92-button A/V receivers. While they represent superb value for money for the non-critical listener, or those who just can't stretch the budget any further, they do not represent anything even approximating sonic excellence. The grain, the sizzle, the exaggerated highs, the boom down below, the poor transitions between channels: these are banished from systems built around a Casablanca.

As I've used a Theta Pro Gen V since its birth, I was familiar with the sound of digital conversion the Theta way. Without being even remotely coy, Theta's Neil Sinclair described the top-level-converter-equipped Casablanca as 'nearly a Pro Gen Va'. 'Nearly' is understatement, and it took a couple of hours and a half-dozen discs before I could distinguish between the Pro Gen Va into the Casablanca, and the latter's on-board converter. Part of that time was spent settling on an interconnect which didn't add to the confusion; the on-board converter had the advantage over the Pro Gen Va by virtue of direct connection inside. After swapping between Discovery, Transparent, and XLO wires, I decided that the Pro Gen Va showed a slight improvement in dynamics, especially the speed of transition from soft to loud, and it offered better low level detail and resolution. BUT - and that's in capitals so you'll notice - it would be hard to justify an extra £2k over the Casablanca-with-on-board-'superior'-DAC.

In this respect alone the Casablanca deserves consideration as a combination pre-amp/converter of no mean abilities. Admittedly, I haven't heard a Casablanca with the entry-level DAC, but I'd be surprised if many Casablanca customers opted for the lesser processor. Given that a Pro Gen Va is a purist device with only a trio of inputs and no pre-amplification, it will retain its appeal to those who simply will not entertain the idea of an A/V ready control centre. What the Casablanca does is swing wa-a-ay to the other side, by retaining 98 percent of the Pro Gen Va's sound, while adding enough inputs, outputs and switching niceties to convert it into a tinkerer's dream.

What makes this device is the way it deals with A/V. It was immediately apparent that the video signal - DATA III to Casablanca to monitor - benefited from the quality of the Casablanca's video cards. I hadn't changed S-video leads when I started the session; I simply replaced a sub-£700 A/V preamp with a Casablanca and was rewarded with the same level of improvement I'd expect had a line-doubler or interpolator been inserted instead. And you don't need to be Spielberg to notice the gains. Cleaner whites, sharper edge definition - hey, it was too blatant and too obvious and too repeatable to be anything other than the influence of the Casablanca.

Sonically, too, the improvements over lesser processors were vivid. Given that most of the sound effects in films are almost impossible to 'reference' - the Harrier jump jet at the end of is about as familiar to most of us in real-life as a llama's cry or an F1 engine from inside the cockpit - so we try to focus on two or three things. We tend to listen for crowd sounds, rainfall, and other real-world, enveloping experiences, mainly to hear whether or not it convinces us.

Do you need to be told that the sound of reality is all-enclosing? That the sound of rainfall doesn't appear to be coming from five discrete sources? The test is this: the better, the more coherent, the more enveloping the sound , the better the surround-sound experience. It's that simple. And, bless 'em, the Theta guys have created the perfect device for show why some of us feel that DTS blows Dolby out of the cinema.

There's almost a consensus as to which scenes do it best, given the shortage of laserdiscs available in both Dolby Digital and DTS form. , and a few others have emerged, but the instant showtime fave has to be . You guessed it: the bit in the preamble where Bond does a 'chute-less sky-dive after a pilot-less plane, and the flyover. You start with the final scene confronting the Russians (Chapter 5) and duck those whizzing ricocheting bullets, move onto the chase after the plane, listen for the rushing wind, savour the explosion and then move into the title song. While only an idiot would doubt the merits of Dolby Digital, which can be positively in terms of impact, dynamics, and sheer energy, DTS definitely wins the day if its realism that's your goal.

But this is nit-picking. Even with the now-passÈ Dolby Pro-Logic, the Casablanca creates a surround sound experience to savour, all the while serving admirably as a funky, ol' two-channel analogue pre-amp when required. It is a product which we'll learn, in about 10 years' time, was one of the milestones in early all-digital home cinema. In 20 years' time, I wouldn't be surprised if it was held in the same esteem as befits a Marantz 7C today. Yes, it's good.

A final word, whatever my obvious lust for this near-perfect device: no sane consumer should even consider purchasing a Casablanca (or any other control center) without trying the Lexicon DC-1 or Meridian 500-series components for insanely good value-for-money, or the Proceed, Krell KAV, Meridian 800, and EAD TheaterMaster equivalents for price-no-object installations. There are no more than a dozen of these devices available at present if you eliminate the mass-market A/V receiver alternatives, but the price span ranges from around £1400 up to absurdity. I've lived with around half of the 'hit list' and can see the merits of every one, but I have to state categorically that, should I suddenly find a spare ten grand or so, I be using a control unit named after my all-time favorite film...