Originally Posted by rockbandguy
What does "ledger lines" mean? (I hope that doesn't sound too stupid to ask. I am new in this "teritory" wink )
And how to I deal with it?
Because I want it to be accurate.
Is there information somewhere that the real sound of the instrument has to be an octave lower?
And does that happen for other instruments, too (besides Vocals and Bass)?

Good question.

A ledger line or leger line is used in Western musical notation to notate pitches above or below the lines and spaces of the regular musical staff. A line slightly longer than the note head is drawn parallel to the staff, above or below, spaced at the same distance as the lines within the staff.
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Originally Posted by rockbandguy
Is there information somewhere that the real sound of the instrument has to be an octave lower?
And does that happen for other instruments, too (besides Vocals and Bass)?

I would say that Bass is generally notated an octave higher than it sounds while Guitar is notated an octave lower than it sounds exactly for the reason that indicated. I have no experience reading or notating voice, but I assume this would also be similar.

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