Digital Recording

Reel-to-reel

- The first digital audio recorders were reel-to-reel decks, introduced in 1972.

- They used a digital technology known as PCM (pulse-code modulation) recording.

With the advent of the 3/4 inches U-Matic in 1971 and other videotapes many studios started to use devices that encoded digital audio into a video signal.

  

Compact Disc (CD)

- Optical disc was originally developed for storing digital audio but is also used to store digital data.

- The CD, available on the market since October 1982, remains the standard physical medium  for sale of commercial audio recordings to the present day.   

  

Digital Audio Tape (DAT )

- Developed by Sony in the mid 1980s.

- Enclosed in a protective shell  size  73 mm × 54 mm × 10.5 mm.

- It records digital audio at 48, 44.1 or 32 KH  sampling rate  at 16 bits quantization.

- DAT can only be recorded in one side.

Alesis Digital Audio Tape or ADAT

- Introduced in 1991, it could record eight simultaneous tracks of digital audio onto S-VHS tape - a similar tape to that used by consumer VCRs.

- It was possible to record a greater number of audio tracks by synchronizing a    few ADAT machines.

Mini Disc (MD)

- Magneto-optical disc-based data storage device initially intended for storage of up to 80 minutes of digitized audio.

- Mini Disc was introduced by Sony in 1992.

- The music format was originally based exclusively on ATRAC Audio Data Compression, but the option of Linear PCM recording was ultimately introduced to attain CD-quality recordings.

- Popular in Japan and Asia as a digital upgrade from cassette tapes, but were not as popular elsewhere.

Solid-State Drive (SSD) and Solid-State Card

- Data storage device that uses  Solid State Memory to store persistent data.

- SSD emulate a hard disk drive interface, thus easily replacing it in most applications.

- SSD using SRAM or DRAM (instead of flash card memory) is often called a RAM-drive.

- Less fragile than hard disk.

- Silent as there are no mechanical parts or delays.

- Faster access time and low latency.

solid-state recorder            flash card                   solid-state drive

MP3

- MP3 (MPEG1 Audio Layer 3) Digital audio encoding format characterized by lossy data compression.

- It is a consumer audio format used for storage and used also as standard encoding for the transfer and playback of music on digital audio player.

- MP3 was designed by the Moving Picture Experts Group and approved in 1991.

- The lossy compression algorithm greatly reduces the amount of data in the audio recording but still sounds like the original.

- A method called PERCEPTUAL CODING compresses the file by reducing accuracy of parts that are deemed beyond the listening resolution of most people.

- An MP3 file can be created using one of the three bit rates, 128 Kbps, 160 Kbps and 190 Kbps, so the higher the number more quality you get.

- At 128 Kbit/s will result in file 1/10 of the size of the normal audio CD.