A CD-R is in fact recordable up to the end of the physical pre-groove which contain information so the recorder can position the laser for recording, normally somewhere in the 77 minutes.

To be able to OverSize CD-R's the Disc-At-Once (DAO) mode of the CD-Writer is utilized. DAO mode, instead of TAO, must provide it's own lead-out (which now can be moved to the very end of the CD-R).
Disc-at-Once has only been added/available with the recent generation of CD recorders and recent firmware upgrades. At the moment about 95% off all CD-Writers support DAO but not all of them support OverSizing!

In DAO mode the CD-R software sends a CUE Sheet (TOC) to the CD-Writer, this CUE Sheet holds information needed for the leadin area (tracksizes & more). A CD-Writer which is not able to OverSize will reject the CUE Sheet when it contains track information which ends past the blank media reported length. The length is read from the pre-groove of the blank media and specifies the last possible position where DATA can be safely written to. A CD-Writer which is able to OverSize will just ignore this length and will try to burn the blank media up to the end of the pre-groove.

Keep in mind that OverSizing is not totally without risk. OverSizing is writing DATA to a place which is outside the original CD-R specifications. This can result that some CD readers (Audio & Data) can have problems reading the last 90 seconds of an OverSized CD-R. There is no guarantee that the quality of the pre-groove, dye and reflective layer, past the reported length, is as good as it is before!

A few CD-Writer software packages warn you that it is possible to damage your CD-Writer when trying to oversize a CD-R. At the moment there is totally no evidence supporting this warning. They just put it in their software just in case it happens and they then can say that you have been warned!

Just take the following in consideration when OverSizing a CD-R:

• There is a possibility that it can damage the CD-Writer.
• Some CD-Writers can't physically move the carriage up to the end of the pre-groove and so can't overburn up to the quantity of the blank.
• Some CD-ROM player can't move their carriage far enough too play an OverSized CD-R.
• The quality of media can be lower than in the normal part of the CD-R.

The following information is stored in the pre-groove:

• The capacity of the disk
• The manufacturer of the disk
• The formulation of the disk
• The type of disk (for example the audio CD-R's for audio CD recorder)
• The supported writing speed
• Hint at each speed for the recording algorithm to use
• Absolute time from the start of the disk
• last possible address where data can be written (TotalSpace)
• last possible address for the last lead out.
  This is the last possible address/position where a lead out can start (from this point on, a complete lead out can be written on the CD-R).

Only a CD-Writer can read the pre-groove, a CD-ROM drive usually can't (as it doesn't need this info to play/read a CD).

More info on 80 Minutes CD-R's can be found on the 80 Minutes CD-R page.

This test can be done on any CD-Writer only if the result is a negative value or a value that is smaller 665 Mb then this means that the writer is NOT capable to OverSize a CD-R. Feurio waits for the writer to return an errorcode when it reaches the end of the spiral, many writers just don't return a valid errorcode (firmware limitation).

Perform the following steps, using Feurio!, to get the OverSize information from a CD-R:

• Startup Feurio! CD-Writer.
• From the action-bar select Extras and then select Rohling-Kapazität testen.
• In the Rohling Kapazität Test window click [Test Starten].
• Wait until the Kapazität-Test beëndet window appears. Enter additional information so to recognize the same type of CD-R the next time.
• When ready click [OK (in Datenbank aufnehmen)] this will save the information to the Feurio! Rohling database (ROHLING.DAT).

Perform the following steps to see an overview of all known OverSize CD-R's:

• Startup Feurio! CD-Writer.
• From the action-bar select Extras and then select Rohling-Datenbank anzeigen.
• This will open the Rohlings-Datenbank window.

Here is the ROHLING.DAT (25-06-1999) that is used to get our information. Just copy it in the Feurio directory (or append it to the existing ROHLING.DAT file). Keep in mind that the info was extracted with a Yamaha CRW4260 CD-Writer. It is possible that it won't detect the info on other CD-Writers (like the Philips 2000/2600 & HP4020/6020).

All known OverSize values are also stored in our CD-R Media List.

Perform the following steps to get the OverSize information from a CD-R:

• Startup CD Wizard and insert a empty CD-R in the CD-Writer.
• In the left part of the CD Wizard window right-click the CD-Writer and select Determine Capacity.
• CD Wizard will first check if the CD-R is already present in it's database. If it is a window will open stating that the inserted media has been found in the Media-list. Click [Yes] to recheck the CD-R or [No] to quit.

Cheaper alternatives to the 80 Minutes CD-R's are:

• Start Nero
• From the action-bar select File and select Preferences.
• In the Preferences window, select Expert Features (or Advanced settings for older versions) and select the Enable oversize disc... feature.
• Choose a Maximum CD Length and click OK (82:59:59 is the maximum value that can be entered) and be aware of the risks explained in the warning.
• From the action-bar select File and select CD Copy.
• A window will appear when a CD is copied which is bigger than 74 minutes, click [OK] to start the oversize copy.

The OverSize feature also works fine when creating your own projects.
Keep in mind that it will only work with CD-Writers that support OverSizing.

Perform the following steps to do an OverSized CD-Copy:

• Start CDRWIN
• In the CDRWIN - CDROM Recording Tools window click Backup Disc.
• in the Backup Disc window click START to begin the CD-Copy operation.
• A window will appear with the following message:
    Warning: Disc longer than 74 minutes. Do you want to continue?
• Click Yes to continue and what for the burn process to finish.

• Start Prassi
• From the action-bar select File and select New.
• In the New Job Set window, mark Copy Job and click OK.
• In the Copy Job window enter a Job Name and click OK.
• Select the CD-Reader (in the left window), click the right mouse-button and select Select as Copy job Source (a green arrow will appear next to it).
• Select the CD-Writer (in the left window), click the right mouse-button and select Select for Recording (a red arrow will appear next to it).
• Preferably mark the Copy the entire source CD... option to first create an image on HD and then writing it (make sure enough HD space is available).
• From the action-bar select File and select Record (or Test).
• In the Prassi CD Rep Plus - Recording and Timing Panel window, click Options.
• In the Options window, goto the Blank Disc part and change the Size of blank media in sectors to the maximum value of 360000 sectors (= 80:00 minutes, 703.1 Mb). The software won't allow you to OverSize a 80 minutes CD-R (yet).
• Use the pull-down button next to Test only and select Record (or any other write mode).
• When ready Click Go! to start the CD-Copy process.

• Start DiskJuggler (1.05.238 or highter).
• From the action-bar choose View and select Options.
• In the Options window select the Defaults tab and change the Max image size to 80 min(s) (for v1.05.238) or 85 min(s) (for v1.05.238-TU RADIUM).
• When ready click [OK].
• From the action-bar choose File and select New.
• In the New Task window select CD Player to CD Recorder and click OK.
• In the Task 1 - CD Image to CD Recorder window select the following settings (all other settings should be left default):

• When ready click Start to start the copy process.

• CDR Fixation
  Close the CD-R so that no further session can be added. This saves about 10 Mb of Leadin/Leadout space which otherwise is needed for the next session.
• CDR Write Mode
  Select the Disc-At-Once mode (also called Session at once)