Overburning is writing beyond the official capacity of a CD-R(W).
This is possible by using the leadout to store (audio) data.
The leadout is used to indicate the end of the disc and contains nothing but zero’s.
According to the redbook standard (the standard at which all CD’s are based on) the leadout must be 90 seconds.
Usually you can even write beyond these 90 seconds but then the data may be unreliable.
The overburning length depends on the media brand.
You should get at least the official capacity plus the 90 seconds for the leadout.
So for example with a disc with a length of 74m43 you should be able to overburn to at least 76m13.
Testing the maximum capacity
The easiest way to determine the maximum capacity of a CD-R disc is to use Feurio! CD-Writer (http://www.feurio.de).
With the option ‘test capacity of CD-R’ (in the Extra’s menu) the program will write data until an error occurs.
After this Feurio shows three values. You must use the lowest value (minus cache memory) which is the only reliable value.
The test is done in simulation mode so nothing is actually written on the disc.
After the test is completed you have the option to store the maximum capacity in a database.
Reliability of overburned discs
An overburned disc is not a standard disc anymore, so it is possible that you will have problems reading it in some CD players.
After the 90 seconds of the leadout the data may be unreliable.
You can see this clearly with Taiyo Yuden discs.
The graph below shows the number of errors of each sector starting from the first sector which contains data errors until the last sector which has been written on the disc.
Starting from sector 345796 (76:50.46) the number of errors increase rapidly.
So although there are actually 347064 sectors (77:07.39) written on the disc, the data is only reliable until sector 345796 which is a difference of 1268 sectors (16.58 seconds).
Many programs also show a warning that the recorder might be even damaged by overburning but to my knowledge this has never happened.
To overburn you will need a recorder which allows overburning. The most popular recorders for overburning are Plextor and Yamaha.
On the Feurio! Website you can see a complete list of recorders which are capable of overburning.
Most current recording software allows overburning: Nero, WinOnCD, CDRWin, Feurio and many others.
Copyright 1999 by Erik Deppe