I've merged all 85 scores and analysed it with friedman:
FRIEDMAN version 1.24 (Jan 17, 2002) [url=http://ff123.net/]http://ff123.net/[/url]
Tukey HSD analysis
Number of listeners: 85
Critical significance: 0.05
Tukey's HSD: 0.226
Means:
Nero 160kbps iTunes LAME 100kbps
4.33 4.24 4.00 3.47 3.17
-------------------------- Difference Matrix --------------------------
160kbps iTunes LAME 100kbps
Nero 0.089 0.331* 0.856* 1.156*
160kbps 0.241* 0.767* 1.067*
iTunes 0.526* 0.826*
LAME 0.300*
-----------------------------------------------------------------------
Nero is better than iTunes, LAME, 100kbps
160kbps is better than iTunes, LAME, 100kbps
iTunes is better than LAME, 100kbps
LAME is better than 100kbps
Graphical results looks like this:
It is safe (for me) to say that:
• Nero Digital (Feb 2007) is better on a wide selection of classical music than iTunes AAC and LAME MP3
• AAC@130 kbps (Nero only, classical music) may offer similar (and even slightly better) quality than top-MP3@160 kbps
• iTunes AAC is better than LAME -V5
• AAC@100 kbps is clearly lower quality than top-MP3@130 kbps.
• Nero@130 kbps > Nero@100 kbps
• MP3@160 > MP3@130 (trivial conclusion but would it appear on a collective listening tests involving several “non-critical” listeners?)
=> Nero Digital AAC (Feb 2007) is what I'll use first, though it's not perfect at this quality setting (-q0,45).