Sometimes I see a C flat in notations..

[riwa]

Im just finding as much sheets as possible to read just for practice. Occasionally I find something that looks wrong. I've been assuming it was made by an amateur but this piece by Steely dan starts with a C flat note. How is it supposed to be interpreted?

https://www.musicnotes.com/sheetmusic/mtdFPE.asp?ppn=MN0089308

[outin]

It just means you play the B, which you would otherwise play B-flat because of the key.

[iansinclair]

Not really that uncommon.  It's usually done to clarify in the writing a harmonic relationship of some kind.  Although it can be a bit confusing at first...

[counterpoint]

For example.

the A flat major chord consist of Ab C and Eb

The A flat minor chord consists of Ab Cb and Eb

[werq34ac]

Harmonically, Cb makes a lot more sense than B natural in this case. Especially since this is a D9 chord. It wouldn't be a D9 chord without that flat 7th and keep in mind that it is a flat 7th instead of an extended 6th.

[riwa]

Thanks for clarification.