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Disc Recording Secrets

Recording CD's places a high demand on the hardware you use, and your computer's system resources. In particular, problems with data transfer may occasion the ubiquitous "buffer underrun" error so many have run across. This message is generated by the disc recorder when its buffer empties and no other data is coming down the pipe. Possible ways to cure the problem include:

• Use a dedicated, high performance hard drive.
  Choose one which is designed for AV applications, either by smart firmware or embedded servo. Either of these techniques will help avoid or eliminate thermal recalibrations which interrupt data flow to the recorder. And they will also usually have faster seek times and burst transfer rates. Buy one which has as large an onboard buffer as possible.
  
• Use a high performance computer.
  The Mac or PC you use can  affect data transfer. The quality of the SCSI bus on Macs can vary, with many of the older 030 and 040 boxes being relatively slow. The kind of bus (e.g. ISA, PCI) and the model host adaptor you use can affect SCSI performance significantly. Even if you are using a Mac with a built-in SCSI bus, it is often a good idea to use a high performance SCSI host adaptor, particularly on newer Macs with PCI buses. On a PC, it is always a good idea to use a PCI host adaptor rather than older ISA versions.
  
• Try not to tax the file system.
  Avoid putting hundreds or thousands of files in a single subdirectory. Keep the structure of your directory tree wide and shallow, rather than narrow and deep. This speeds drive access.
  
• Defragment your hard drive.
  Again, this speeds drive access.
  
• Use a recorder with a large buffer.
  This helps to insure that the recorder can withstand periods of time when no data is flowing down the SCSI bus. The more the merrier, and some recorders allow you to add more yourself. Purchase a recorder with at least 512K of buffer, and preferably 1024K or more.
  
• Use hard disk caching software.
  On some systems, this may help accomplish the same thing as an onboard hard drive buffer.
  
• Utilize any special options the recording software offers.
  For instance, in CD-It! All versions 2.5.8 through 2.5.10 there are a couple hidden recording modes available.
  
  
  • One, the "Blind" mode, is useful only for versions of the Philips CDD2000 recorder with v1.20 firmware or earlier. This mode is obsolete, since the firmware can now be updated to 1.26 (as of this writing.)
    
    
  • The other, "Polled" mode, makes the data transfer slower but more secure, sometimes helping when a drive has buffer underruns without any reasonable cause.
    
    
  • Press the spacebar and either P(for Polled) or B(for Blind) and click on the version number (in the main CD-IT!ALL dialog) to switch between the various modes.
    
    
  • Normally there is NO NEED to change the mode! In Toast 3.0 it has been removed because Toast now uses the optimal mode for each drive. Toast 3.0 also offers use of the Mac's RAM for buffering purposes.
  
  
• Record on a dedicated computer (or turn everything else off.)
  If you use the computer for things other than recording discs, try to turn all those things off before starting a recording session. On a PC, this means TSR or background programs, unneeded device drivers, etc. Remark-out the lines in system files (autoexec.bat, config.sys, system.ini, win.ini, etc) or use different versions of the system files.
  
  On a Mac, it is usually simplest to turn off all extensions by rebooting with the shift key held down.

  And, of course, NEVER run another program during a recording session. Not even Windows or MacOs functions/utilities. Just don't touch nothin'.