Tenor Saxophone is written an octave higher, to keep the notes from spanning both bass and treble clefs.

It's also written one step (two half steps) higher than the pitch it sounds. So when the piano or guitar plays a Bb, the tenor sax plays a C in order to play the same pitch. The alto sax plays a G. There is a good reason for that, but it's another post.

When reading a chart, if notes on the ledger lines are higher than F, It gets a bit difficult to sightread. Same for lower than C on the bass clef.

Notes ♫

Bob "Notes" Norton smile Norton Music
https://www.nortonmusic.com

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