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What is pre-mastering? Stage one - your disc checked for data strength in conventional duplication industry-standard CD duplication tower and stored electronically (hard drive) and then “burnt” directly back to a CD-R. This tests signal strength and reflectivity of organic layer on the CD-R and surface for any faults, scratches or other anomalies. The firmware that drives the duplication towers is written around the rules set out for the manufacture of CD's or DVD's (whichever sub format) and will reject any discs not made properly; for example if a multi-session disc or “packet written disc” falls outside the specification and would fail, the master disc must then be re-written as a single session finalised disc. The disc is then virus checked using the latest trend software and is despatched to plant. Stage two – the same tests are carried out again but more stringently on dedicated test equipment, also the signal strength is monitored against other criteria, it is very rare that a disc that passes stage one test will fail stage two tests. In addition to the stage on test we also check all discs for autorun facilities, some discs depending on their content will not have this but the majority do. We can also create this facility if a customer requires.
What is a glass master? Must I have one? A glass master is an exact reproduction of the original master, a photo sensitive layer applied to the “glass” is etched by a powerful laser before being “fixed” by a chemical process. This glass master is then processed through a bath in which an electrical charge is applied to build up a layer of various metals. Once this layer is around 300 microns thick (0.3 mm) the process is stopped and this layer is removed from the glass master and trimmed. It is this “stamper” (a mirror of the raw data) that is used in the presses that heats (at great temperature) the raw material of the disc – polycarbonate. The glass master in an essential part of the production process, once made it is stored in readiness to produce other “stampers” should a re-press be required or more than 20,000 discs produced. What different types of
discs can I have manufactured?
Physical sizes are options but to talk of different
formats is too varied a subject. It is a job for the creative people
who write the content. What packaging options are available to me for my CD-ROM? Your CD/DVD packaging options are wide and varied - for example we can provide specialist packaging production from over 22,000 different cutting forms! Standard packaging is also available as print specifications from our existing sites. What software applications should I have my CD artwork made in? All the ones specified in the print templates.
What's the difference between your CD-ROM and CD-R duplication services?
A CD-R disc is manufactured to allow data to be
copied (recorded) by a special device called a CD-R writer. The
CD-R has a recording surface that uses a special dye that can be
ablated by the laser in the writer. When writing to the CD-R disc,
the laser burns the pattern of data into the dye on the recording
side of the CD-R. There is a special grooved, spiral track that
the laser follows when writing the data. CD-ROM is for projects that require replication or pressing and generally over 500 units upwards to many, many millions. They are inexpensive to produce, especially in quantities of 1,000 plus. CD duplication or ‘print and burn’ is for quantities from 100 upwards. As there is no glass mastering or “stamper” production required, the smaller quantities are cheaper to produce and offer much quicker turnaround times. We often produce 1,000 or 2,000 discs as CD-R
production and not CD-ROM production because of the lead time restrictions,
even though they are more expensive.
Do your cut CD's (shaped CD's) take longer to manufacture than
normal CD's?
Yes, it doubles the production time as it is a completely different process and is carried out in the same plants.
We can start as soon as we receive your, master disc and your artwork approval. A typical order will be with you within 7-10 working days. With short run taking 1-3 days.
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