Quality of 8x DVD+R disc burning at 12x speed
LG GSA-4163B	LG GSA-4160B

Both devices use a three-zone Z-CLV algorithm here. They also switch from one zone to another in the same time, so the burn sessions had almost the same duration. There were no problems during the burning process as the clear and smooth graphs show. The discs were subsequently read without problems, too.

You get high-quality DVD+R disc with both drives, but the GSA-4163 is better among the two. The total of PI errors is much smaller (6215 against 8666) on the disc burned by the new model, and the total of PI failures is better almost in double, too. So, the GSA-4163 surpasses its predecessor in tests by a small but stable margin from disc to disc.

Beta/Jitter and TA Test (Inner, Middle, Outer)
for the disc burned by the LG GSA-4163B

 


 

The jitter is within the norm and is uniform on the entire disc. The asymmetry is normal, too. The graph clearly shows the moments where the drive switches between the burn speeds. What£r curious, the laser power and, accordingly, the beta value are going down rather than up on each step of the Z-CLV algorithm. TA Test says the drive finds it difficult to maintain the required pit/land lengths, especially on the second half of the disc at 8x speed. The deviations of the lengths are small and slightly affect the overall result, though.