1653S+EAC able to overread into Leadout

vbimport

#1

Hi there!

I just found out that despite the fact that EAC (Exact Audio Copy) claims that the 1653S is not able to overread into Leadout, it IS possible.

Using the reference cd “Best of The Doors CD1” I was able to ripp the last song completely with the “missing” 12 samples at the end (read offset) without any errors when using one (1) specific setting.

That is: Secure Mode, Accurate Stream ON, Drive caches ON, C2 error information OFF!

All results were compared to the ripp of my Plextor 48/24/48a, which is able to overread into leadout by itself. CRCs did match when results matched, as did the files in wav and bytewise comparison.

What makes me post this here is the question, if the drive shouldn’t be able to do the same trick in all others modes as well?

As far as I can say overreading into leadout does not work anymore once you turn on C2, or use any other mode than Secure (with the aforementioned settings). You get sync errors in Secure with C2 enabled, and Timeout problems with Burst mode.

The resulting files do not match the original anymore, where the really strange thing is: They do include the 12 ending samples (which are all 00), but the last part of the song BEFORE the leadout is read wrong (like ff where 00 should be)!

This seems to be a problem of firmware rather than hardware/EAC to me.

Any idea how to fix that? :rolleyes:


#2

Interesting! It may be firmware protection/deficit??


#3

I did some more testing and found out that enabling/disabling Drive Cache doesn’t matter. Works with or without it as long as C2 is not activated.


#4

What puzzles me most is that the use of C2 error correction is what leads to errors! I guess that the drive uses it’s C2 for burst as well and that it is also used in Paranoid mode.

So in the end it might all come down to C2 to introduce errors when it’s meant to do the opposite.


#5

Just to correct one misconception that may bite you…

In EAC, the option “Drive caches audio” does NOT enable or disable it - the option, if SET, warns EAC that the drive DOES cache audio, so action must be taken to invalidate the cache to get a real re-read and not a cache return.
The “invalidate cache” action, used to be a drive reset, but repeating that often upsets some drives - the current way is to go for a pre-read in order to flush the cache through before getting to the bit that is actually to be re-read.

Enabling the option when not required, may slow down the reading.
Disabling the option when it is needed, will severely degrade EAC’s error detection and recovery.

Similarly, the “Accurate stream” option tells EAC not to waste time synchronizing inaccurate stream segments by matching overlaps.

“C2 Error” is an option that many recommend turning off, as the drive’s C2 reporting is often less accurate than EAC’s double read and compare.
Using C2, if the drive can do it, improves ripping speed.


#6

I think I did understand these concepts beforehand. I just had to go through all the options to find out, what makes my Liteon overread into the leadout, and what keeps it from it. Or better to say: what makes it read wrong data!?

Because that’s actually what’s happening, the drive reads wrong data BEFORE even reaching the leadout zone, when you use wrong switches (that is make use of C2 in conjuction with enabling overread into leadout to overcome the offset).