Okay, there are a couple of things that made my head spin when I was brand new to bass, so I was never sure if I got them figured out. Im going to see if I got it right. Im going to make some statements that I believe to be true. Please correct any statement that is not true as one idea leads into the next. Middle C is a specific note - it is a C, but in a specific octave. Middle C has a specific tonality. Middle C written for a bass instrument (bass clef) would appear on the first ledger line above the normal staff. Middle C written for a higher pitched instrument (treble clef) would appear on first ledger line below the normal staff. Middle C is the note played on a bass guitar at the 5th fret on the first string (or the open high C string on a six string EBG) Bassists often refer to the 1st string of a six string bass guitar (strung and tuned BEADGC) as a high C string, this is probably reference only to the fact that it is an extension of the normal 4 strings range as well as the fact that this note when written, is above the standard bass staff. The note which is sounded by a bass players high C string is known (tonally) as middle C. Am I right, wrong or what?