"On the fly" good or bad idea?

I am wondering if it is a good or bad idea to use the “on the fly” feature when backing up a CD using two Plextor drives.

My computer has a Plextor 712 and a Plextor 716. I use audio error detection when backing up a CD with Plextools.

Is there any reason to believe that an “on the fly” copy may sometimes be less than 100% perfect compared to a copy made from the hard drive? Or will either method be 100% perfect, as long as two Plextor drives and audio error detection are used?

If either method will work equally well, it seems to me using “on the fly” would be faster and would not put as much wear on the hard drive.

A 2nd question: is there any way to “verify” a CD backup to the original with Plextools? Or must you buy the professional version of Plextools to do that?


There are certain things to check first - Make sure your source and destination drives are running in DMA mode, the highest they support. Your source and destination drives need to be on 2 separate channels.


Primary Master IDE System C
Primary Slave IDE CD/DVD ROm

Primary Slave CD/DVD ROM

Set the reading speed to at least twice that of the writing speed and set a sufficient memory buffer. Run a test/simulation to make sure things work properly.

I personally have no problem doing on the fly copies…

For audio backups I use reading 16x writing 8x

There should not be a problem in terms of data integrity, make sure your destination drive can keep up, make the RAM buffer bigger and test it first. The first few times you do this run a verify.

CDs are ok in my experience below 40X! Depends on your system! DVDs not!

I use on-the-fly for DVD movies too but I only record at 4X in those cases and use a PX-716A as source (external drive) and my PX-712A as target (internal drive). 8X also works but that’s pushing the limits for my system (read: I can’t start any applications because it will result in buffer underruns). At 4X I can use my system just fine.

Okay, but buffer underruns shouldn’t be of any problems, as the burner only will wait for data, right? Otherwise I don’t see the meaning of the bufferunderrun protection.


Of course. But personally I try to prevent these underruns if I can. Call me crazy :wink:

sucky windows will “check” all connected drives, the result is buffer underruns.
You can see and analyze that easily when burning with DVD/ImgBurn and starting exploDer up (click on “my computer” and it will stall). The log will show you write retries immediately. :Z

Given an almost perfect source disk(a QS 99 verbatim), a decent fast reader(my nec 3520), seperate ide controller/cables(standalone masters), a fast good burner(LG 4163B), a 6 1/2 minute 16x COF is very achievable!
No multitasking!