A hard disk recorder is a type of recording system that uses a high-capacity hard disk to record digital audio or digital video. Hard disk recording systems represent an alternative to more traditional reel-to-reel tape or cassette multitrack systems, and provide editing capabilities unavailable to tape recorders. The systems, which can be standalone or computer-based, typically include provisions for digital mixing and processing of the audio signal.
Prior to the 1980s, most recording studios used analog multitrack recorders, typically based on reel-to-reel tape. During the 1980s and 90s, companies like New England Digital and Fairlight began to include hard disk recording capabilities in their high-end systems. The high cost and limited capacity of these solutions limited their use to large recording studios, and even then, they were usually reserved for specific applications such as film post-production.
With the takeoff of the compact disc, digital recording became a major area of development by equipment makers. Several affordable solutions were released during the late 1980s and early 90s; many of these continued to use tape, either in reels, or in more manageablevideocassettes. However, in 1991, Fairlight ESP Pty Ltd developed the MFX2, the first 24 track disk recorder. In 1993, iZ Technology Corporation developed RADAR (Random Access Digital Audio Recorder distributed by Otari Corporation), designed to replace 24 track tape machines. By the middle 1990s, with the steady decline of hard disk prices and the corresponding increases in capacity and portability, the cost of hard disk recording systems had dropped to the point where they became affordable for even smaller studios. Though there are several other types of digital recorder still in use, hard disk systems are rapidly becoming the preferred method for studio recording. On January 14, 2004, Engineers from Fairlight, Waveframe and AMS were awarded Scientific and Technical Academy Awards for the development of hard disk recording technology .
One major advantage of recording audio to a hard disk is that it allows for non-linear editing. Audio data can be accessed randomly and therefore can be edited non-destructively, that is, the original material is not changed in any way. Non-linear editing is not inherent to every hard-disk recording system, however. Different manufacturers implement different degrees of this facility. In addition, hard disk recorders offer some disadvantages, including the limited capacity and relatively high cost of replacement drives, as well as a reduced ruggedness of hard disk recorders as compared to tape-based systems.
Hard disk recorders are often combined with a digital mixing console and are an inherent part of a digital audio workstation. In this form complex tasks can be automated, freeing the audio engineer from 'performing' a mix.
A personal computer can be used as a hard disk recorder with appropriate software; nowadays this solution is often preferred, as it provides a more flexible interface to the studio engineer. Many studio-grade systems provide external hardware, particularly for the analog to digital conversion stages, while less expensive software systems can use the hardware included with any modern computer. The major constraints on any hard disk recording system are the disk size, transfer rate, and processor speed. Some systems use "lossy" digital audio compression to minimize the first two factors. This solution is becoming increasingly rare, thanks to rapid increases in hard disk capacity.