A master reel is a single-track mono or two-track stereo reel-to-reel which stores the master recording

Master recording

A multitrack recording master tape, disk or computer files on which productions are developed for later mixing, is known as the multi-track master, while the tape, disk or computer files holding a mix is called a mixed master.It is standard practice to make a copy of a master recording, known as...

 of a professional record album

Album

An album is a collection of recordings, released as a single package on gramophone record, cassette, compact disc, or via digital distribution. The word derives from the Latin word for list .Vinyl LP records have two sides, each comprising one half of the album...

. These tapes are archived in a cold room or a very cold safe. A backup copy of a master reel, known as a safety copy, is always made to ensure the recording will survive a failure of the master reel. Most modern studios

Recording studio

A recording studio is a facility for sound recording and mixing. Ideally both the recording and monitoring spaces are specially designed by an acoustician to achieve optimum acoustic properties...

 use CDs

Compact Disc

The Compact Disc is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage , write-once audio and data storage , rewritable media , Video Compact Discs , Super Video Compact Discs ,...

 or hard drives as their master format. The format of a master reel is outdated for most modern recording studios

Recording studio

A recording studio is a facility for sound recording and mixing. Ideally both the recording and monitoring spaces are specially designed by an acoustician to achieve optimum acoustic properties...

.