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Recording medium comparison

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This article details a comparison of audio recording mediums.

Further information: Gramophone record

Format	Typical length
Cylinders	around 2 - 4 minutes
78 record	around 3 - 5 minutes per side
45 record	often around 4 minutes (EP: 7 minutes) per side, up to 6 per side, in some cases even a few minutes longer.
LP record	up to 30 minutes per side, though some LPs have a longer time by a few minutes.
Audio cassette	usually 30 or 45 minutes per side, 60 minutes per side have also been sold although the tape is more prone to stretching or breaking.
8-Track	up to 100 minutes, often 45 to 80
Compact disc	Earlier discs: up to 74 minutes (or up to 650 MB of data files)
Compact disc	Later discs: up to 80 minutes (or up to 700 MB of data files)
Recordable discs	Up to 99 minutes, unlikely to be reliable (mistracking after 90 Minutes)
Reel-to-Reel	1.5 hours (both sides) if recorded at 7.5 inches per second (ips) on a standard 1800 ft reel. Professionals record at 30 ips on 3600 ft reels that will fit 22.5 minutes (one side only). A 3600 ft reel can hold up to 48 hours if recorded in mono (4 sides) at 15/16 ips.
Minidisc	Earlier discs: 74 minutes up to 296 minutes, dependent upon compression used.
Minidisc	Later discs: 80 minutes up to 320 minutes, dependent upon compression used.
Hi-MD	Up to 13 hours on a standard 80-minute MiniDisc.
Hi-MD	Up to 45 hours on a 1Gb Hi-MD (MiniDisc)
Digital audio player	Roughly 18 hours of playback per 10 GB, assuming an average bitrate of 128 kbit/s. Roughly 37 hours with 64 kbit/s and roughly 7 hours with 320 kbit/s.
DVD	around 8.5 hours per layer (4.7 Gb), with a maximum of two layers per side, which roughly equals 35 hours on a dual layered, two sided disc (can change due to compression).
SACD	Hybrid: A "Red Book" layer compatible with most legacy Compact Disc players, dubbed the "CD layer," and a 4.7 GB SACD layer, dubbed the "HD layer."
	Single-layer: Physically a DVD-5 DVD, a single-layer SACD includes a 4.7 GB HD layer with no CD layer.
	Dual-layer: Physically a DVD-9 DVD, a dual-layer SACD includes two HD layers totalling 8.5 GB, with no CD layer.
HDDVD	Single-layer: 15 GB
HDDVD	Dual-layer capacity: 30 GB
Blu-ray	50 GB (23 Hours)

The typical duration of a vinyl album was about 15 to 25 minutes per side, except classical music which could extend to over 30 minutes on a side. If a side exceeds the average time, the maximum groove amplitude is reduced to make room for the additional program material. This can cause hiss in the sound from lower quality amplifiers when the volume is turned up to compensate for the lower recorded level. An extreme example, Todd Rundgren's Initiation LP, with 36 minutes of music on one side, has a "technical note" at the bottom of the inner sleeve: "if the sound does not seem loud enough on your system, try re-recording the music onto tape." The total of around 40–45 minutes often influenced the arrangement of tracks, with the preferred positions being the opening and closing tracks of each side. Although the term EP was commonly used to describe a 7" single with more than two tracks, technically they were not different from a normal 7" single. The EP used reduced dynamic range and a smaller run-off groove area to extend the playing time. However, there are examples of singles, such as The Beatles' "Hey Jude" or Queen's "Bohemian Rhapsody", which were six minutes long or more. (in 1989, RCA released 'Dreamtime' by the band Love and Rockets, which clocked at 8:40). These longer recordings would require the same technical approach as an EP. The term EP has also been used for 10" 45 rpm records, typically containing a reduced number of tracks. Vinyl albums had a large 12" album cover, which also allowed cover designers scope for imaginative designs, often including fold-outs and leaflets.

1 See also
2 References
3 Further reading
4 External links

References

Fadeyev, V., and C. Haber (2003). "Reconstruction of mechanically recorded sound by image processing". Journal of the Audio Engineering Society 51 (December): 1172.
Lawrence, Harold; "Mercury Living Presence." Compact disc liner notes. Bartók, Antal Dorati, Mercury 432 017-2. 1991.
International standard IEC 60098: Analogue audio disk records and reproducing equipment. Third edition, International Electrotechnical Commission, 1987.
College Physics, Sears, Zemansky, Young, 1974, LOC #73-21135, chapter: Acoustic Phenomena

External links

Creating a vinyl record
VinylHunt.com — A free directory of Record Stores in the US that offer new or used vinyl.
Popsike.com — Price Guide / Database of auction prices of rare vinyl records.
YouTube — Record Making With Duke Ellington (1937) A look at how early 78 rpm records were made.
Vinylfanatics.com — A website devoted to vinyl records. News, reviews, forum.
Kiddie Records Weekly — Recordings and case images from children's records of the 1940s and 1950s.