> On 7 Oct, 2016, at 05:41, Derek Morton <[email protected]> wrote: > > No matter how many times I tried to rip them with a superdrive they had > errors.
Some drives, even within a given type, have better tracking and error correction than others. I have a couple of ancient TEAC CD-ROM drives (one 32x SCSI, one 40x ATAPI) which are the bee’s knees at handling dodgy CDs that most other drives won’t even touch. The only drive I own which beats them on CDs is a Sony DVD-ROM drive which, ironically, falls over if you so much as breath on an actual DVD which you ask it to read. I retired that particular drive from my parents’ G3 when it consistently failed to even recognise clean, pressed, single-layer DVDs that my PowerBooks (Pismo and Ti) both had no trouble with. IIRC, Apple themselves favoured Panasonic/Matsushita (same company), whose drives aren’t bad but aren’t outstandingly good either. You can also expect some compromises in a compact or slot-loading format. In my experience, most of the full-size, tray-loading “super multi” DVD writers are quite competent at reading substandard discs. Part of this will be due to DVD writing placing strong demands on the quality of the spindle and transport. From there, the main differences between drives will be in the tracking and error correction algorithms; some drives can “turbocharge” the latter by exploiting the 2D nature of the error-correcting code, while others merely apply the two layers sequentially (and some very poor drives might ignore one of the layers entirely). I suppose Blu-Ray drives might gain some advantage in the tracking category, due to the finer track pitch of the newer standard. They’re also likely to carry newer types of ECC hardware and algorithms, which are more likely to be capable of “turbocharging” the decode process. Some of the better CD-ROM drives, however, did this from the beginning, which is what makes them stand out. - Jonathan Morton -- -- ----- You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To leave this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
