OVER the past 15 years computer technology has utterly transformed the face of both music-making and sound recording. Poorly programmed drum and keyboard parts are readily detectable even to the untutored ear, but when the job is done properly it is more or less impossible to detect the difference between a programmed and a live performance. ''Most of the music you hear nowadays is programmed. You can't replace fine performance, but the average stuff now generally goes down via a computer,'' said Mr Noel Quinlan, managing director of the Sound Department, one of the most technologically sophisticated recording studios in Asia. Mr Quinlan, an Australian, established the Sound Department in 1986 after a period working in Los Angeles as a composer of film and television soundtracks. While in the US, he was introduced to the Society of Motion Picture Technical Engineers (SMPTE) time code system, technology which allows the precise synchronisation of sound or music with individual frames of film copied on to video tape. He returned toHongkong determined to set up a studio with the same capabilities. ''I built the Sound Department specifically to do music for film using technology as a tool,'' Mr Quinlan said. After initially looking at the computerised music system developed by the now defunct American Synclavier Corporation, Mr Quinlan decided to buy the Fairlight CMI (Computerised Musical Instrument) developed and built in Sydney. ''We went the Fairlight route because they were the only ones doing equipment that could handle digital editing and very large sampling,'' Mr Quinlan said. ''It turned out to be a good idea. Equipment gets to be old fashioned very quickly in this business. Fairlight, on the other hand, used the premise of absolutely first-rate hardware and then rewriting the software on a constant basis.'' The Sound Department uses two Fairlights, bought for $1.3 million each, one of which is in constant use while the second acts as a back up and, when necessary, a source of spare parts. In its present configuration, the Fairlight is a 16-channel, 24-track digital sampler and direct-to-disc recorder. This means instruments can be sampled into the machine, one note at a time, and performances can be programmed on those notes. Data is stored on two, one-gigabyte hard disks. Mr Quinlan's Fairlights are the heart of a system in which each piece of equipment is completely synchronised to a time code. Other processing devices include IBM and Macintosh computers. The Sound Department has recently taken delivery of a Mac 2vx as the front end controller for a digital editing system. The studio also uses a variety of different sequencers compatible with systems used by freelance programmers, including IBM and Macintosh, to whom Mr Quinlan sub-contracts the time-consuming work of keying in compositions and arrangements. With support from Sydney, the Sound Department has almost become its own service centre. Although Mr Quinlan has been a professional musician since his early teens, he trained as an electronics engineer and, therefore, knows enough about the equipment toisolate faults. ''We're quite literate at doing our own repairs but, with the technology involved, there's not many people who can handle work of this kind,'' he said. ''The only thing you can do is identify the problem area, remove the card, and replace it.'' Notwithstanding the success of Digital Audio Taping (DAT) in professional studios, Mr Quinlan believed the days of recording tape were numbered. ''We record most of our stuff now direct to hard disc. To this end, rather than have amplifiers, we have devices such as the ART SGX 2000 which will approximate every amplifier, pre-amlifier and speaker array that's ever been set up,'' he said. ''The only live thing sometimes is the drums - and that can be done just as quickly on the Fairlight.'' But even hard disc has its disadvantages. Mr Quinlan recently lost the greater part of six months' work when a disc with two albums worth of data on it crashed. This served to delay the appearance of what is one of the Sound Department's most successful projects to date - Middle Kingdom, a recording of ancient Chinese melodies performed by a mixture of computers and live performers with Mr Quinlan's arrangementsaimed at making the music more acceptable to Western ears. ''It's actually a combination of hardware, software and wetware,'' he said. ''It's been quite ground-breaking and, through Warner's, has done well internationally. It was released in February and, in Hongkong, it is still selling at a rate of 200 to 300 copies per week.'' ''You can't replace musical ability with technology but, if you've got the ability, it's a wonderful tool,'' he said. FACTFILE NAME OF COMPANY: The Sound Department. TYPE OF BUSINESS: Fully computerised recording studio. NUMBER OF EMPLOYEES: Seven, plus a team of freelance musician/programmers. HARDWARE: Two Fairlight CMI 3s, Apple Macintosh 2vx, IBM 486. All sound processing devices and tape transports are computer controlled.