In reply to:
I would be curious to see if you have problems ripping.
Some discs caused cdparanoia to retry more than I'd like, and the last two tracks of Disc 3 totally failed in my drive (which had no problems with the Cactus-protected Natalie Imbruglia album), giving kernel messages like
Sep 9 21:42:32 suilven kernel: hdc: packet command error: status=0x51 { DriveReady SeekComplete Error }
Sep 9 21:42:32 suilven kernel: hdc: packet command error: error=0x54
Sep 9 21:42:32 suilven kernel: ATAPI device hdc:
Sep 9 21:42:32 suilven kernel: Error: Illegal request -- (Sense key=0x05)
Sep 9 21:42:32 suilven kernel: Illegal mode for this track or incompatible medium -- (asc=0x64, ascq=0x00)
Sep 9 21:42:32 suilven kernel: The failed "Read CD" packet command was:
Sep 9 21:42:32 suilven kernel: "be 04 00 04 a6 fc 00 00 04 f8 00 00 "
[Edit: using cdda2wav or cdparanoia executable instead of grip's embedded cdparanoia didn't help]
But a colleague's Mac did these for me (and saved me time by doing the downsampling for me, giving Lame less work to do).
I've now encoded the first book, and I'm going to listen to it for a bit before going further. I found it was a bit quiet, so I used "normalize" to add 5dB or so. I also omitted the "Chapter Seven, continued" introductions where chapters were split across two CDs, as those boundaries disappear on the Empeg (simply omitting the first 250 audio frames from the rip). I kept the other metadata lines, though.
I set Lame to use VBR level 9, in mono, resampling to 22.05kHz and lowpass filtering at 10kHz. This gives me something that still sounds very good through headphones, so I expect that it's more than good enough for the car. It comes out at 181MB for the full 8h25m - only 50.11kb/s, in other words.