Personal multiformat listening test at ~130 kbps, based on classical (baroque) music only Options

[tigre]

To be honest, i think it's strange that a 24bit file is smaller than a 16bit one, and i would also asume that the Pro codec would generate bigger filesizes/bitrates at the same quality level ? Has anyone done a good test off the WMA9 Std. codec and compared it with the Pro codec, at Q90 (VBR, no 2-pass "ABR") ?

When talking about WMAPro "24bit" just means that it is capable of encoding audio files with 24bit resolution. But since we are talking about lossy mode here: As you probably know, lossy codecs save space by 'throwing away' or adding indaudible information, e.g. low volume signals masked by loud signals. At normal volume information carried by bits # 17 ... 24 is masked anyway. So a lossy compressed file created from a 24bit source won't need more space than one created from a 16 bit source in most cases.

WMA9 Pro is not just an extension of WMA9 Std. It's a different codec. If WMA9 Pro is *better* than Std. it should produce more transparent quality at identical file sizes OR smaller file sizes at identical/comparable quality, shouldn't it? That's exactly what you observed.