What is the Length of Cd

What is the Length of Cd.


Author’s Notes

Physical, Logical and File

Arrangement Standards

Recording Hardware

Recording Software

Recording Speed

Physical Compatibility

> Disc Size
and Chapters

Audio Recording

Digital Pictures on CD

Duplication, Replication

and Publishing

Disc Labeling


Handling, Storage

and Disposal



Disc Testing



Disc Construction and


Appendix A –


Reading and Resources

Appendix B – Industry

and Product Contacts


Near the Author

CD-Recordable Glossary
White Papers
Archived Storage (COSA)
Optical Websites


What are the physical sizes of CD-R and CD-RW discs?

CD-R and CD-RW discs come in standard 12 cm (120 mm) and 8 cm (80 mm) sizes. The most popular is the larger 12 cm type which has the same physical dimension as most commercial audio CDs and computer software CD-ROMs. eight cm discs are less common but, thanks to their smaller size, are gaining popularity for use in consumer electronic devices such as portable compressed digital audio players, digital even so paradigm cameras and data storage products like miniature CD recorders.

What about business organisation carte CD-R and CD-RW discs?

Beyond the conventional 8 cm and 12 cm sizes some manufacturers offer discs shaped like business and credit cards or in other novelty forms. These do non adjust with Orange Book specifications and, as a result, may not write and play dorsum in all recorders or reading devices. Post-obit manufacturer instructions is always the best grade.

What capacities of blank CD-R and CD-RW discs are available?

Manufacturers commonly express disc chapters in terms of how much Red Book digital sound (in minutes) and computer data (in megabytes) a disc can contain. Historically, 63 minute/550 MB (12 cm) and 18 minute/158 MB (viii cm) discs were once available just are now rendered obsolete past advances in recording technology. Currently, 74 minute/650 MB, 80 infinitesimal/700 MB (12 cm) and 21 minute/185 MB (8 cm) discs are the market standards.

What near 34, 90 and 99 infinitesimal CD-R discs?

A few media manufacturers take recently introduced 34 minute/300 MB (8 cm), 90 minute/790 MB and 99 infinitesimal/870 MB (12 cm) CD-R discs. To achieve these higher capacities such discs do not suit to Orange Book specifications and, every bit a outcome, may not write in all recorders, be attainable to all software or readable in all players and drives. Using 34, xc and 99 infinitesimal CD-R discs is therefore not recommended.

How much information tin can actually be stored on CD-R and CD-RW discs?

The amount of data that can be written is determined past the disc’s recording chapters equally well as the physical and logical formats used.
Each of the five main CD physical formats devotes a unlike corporeality of space to user information (audio = ii,352 bytes/block, CD-ROM Mode 1 = 2,048 bytes/block, CD-ROM Mode 2 = 2,336/bytes/cake, XA Form i = 2,048 bytes/block, XA Form two = 2,324 bytes/block). For whatever given data format disc capacity can be calculated by multiplying the appropriate user information surface area size past the CD data transfer rate of 75 blocks per second by 60 seconds past the minute size of disc. For example, a fourscore minute disc written in CD-ROM Way 1 format: user information expanse of 2048 bytes/block 10 75 blocks/2nd = 153,600 bytes/second ten sixty seconds = nine,216,000 bytes/infinitesimal ten 80 minutes = 737,280,000 bytes. This rounds to roughly 700 MB (dividing by 1,024 to convert into KB and again past 1,024 to convert into MB). Information technology should be noted, however, that in the real world capacity can vary slightly among discs from different media manufacturers.

For discs written with computer data the logical format used also consumes space available for user data. For example, the overhead for the first session of a multisession disc consumes 22 MB of space and each subsequent session thereafter uses 13 MB. And in the case of CD-RW discs which are formatted for random packet-writing, usable capacity is reduced by roughly 23%.

CD-R and CD-RW Disc Capacities
(capacities indicated in bytes)


(ii,352 Bytes/Cake)

Manner 1
(two,048 Bytes/Cake)

Fashion 2
(two,336 Bytes/Block)

Form one
(2,048 Bytes/Block)

Form 2
(2,324 Bytes/Block)
8 cm 18 min 190,512,000 165,888,000 189,216,000 165,888,000 188,244,000
viii cm 21 min 222,264,000 193,536,000 220,752,000 193,536,000 219,618,000
12 cm 63 min 666,792,000 580,608,000 662,256,000 580,608,000 658,854,000
12 cm 74 min 783,216,000 681,984,000 777,888,000 681,984,000 773,892,000
12 cm 80 min 846,720,000 737,280,000 840,960,000 737,280,000 836,640,000

What is the difference betwixt 74 and 80 minute discs?

The but meaningful difference between most 74 and eighty infinitesimal discs is their storage capacity. Typically, this increment in usable space is achieved by tightening the coils of the pregroove (track pitch). This allows the disc to accommodate a longer pregroove and therefore a larger recordable surface area.

Are there whatever compatibility issues when using eighty minute instead of 74 minute discs?

Originally, fourscore infinitesimal discs were specialized products for use in audio premastering studios just now have become commonplace and compatible with most software, recorders, readers and players. In some instances, however, older recorders and premastering software must be upgraded to accommodate fourscore minute discs. It is, therefore, advisable to bank check with the manufacturers of your products and ensure that the latest versions of software and firmware are being used.

What is overburning?

Overburning (sometimes called oversizing) is the ability to write across the manufacturer’due south declared capacity on a CD-R or CD-RW disc. This is accomplished past using the disc’s Lead-Out Area (reserved to indicate to a reading device that the finish of the data has been reached) to store the additional user information. Although some recorders and premastering software packages accept the ability to overburn a disc the practice is not permitted by Orangish Book standards. Overburning might affect product warranties and issue in lost information so it is not recommended.

What is the Length of Cd

Source: http://osta.org/technology/cdqa7.htm