Put a capo (or two or three) on the headstock. If the "dead spots" don't move or go away, you either have a fret or (rare) a truss rod problem. The is the most likely cause if the problem is as severe as you describe. If they move or go away, they are true dead spots caused by neck resonance.
- What are dead spots on a guitar?
- Do all guitars have dead spots?
- Why am I getting dead notes on my guitar?
- How do you tell if a guitar is damaged?
What are dead spots on a guitar?
A dead spot, defined by an abnormally fast decay of the fundamental tone, is caused by damping due to energy transfer from the string to the instrument body. For a well-balanced instrument the bridge proves as practically immobile, while the neck is flexible and exhibits resonances.
Do all guitars have dead spots?
"All guitars will have a dead spot some place unless they are made out of concrete. A good finger vibrato would go a long way in letting the note regenerate itself as well !"
Why am I getting dead notes on my guitar?
If the entire string is dead (I'm assuming you've changed strings) it's likely a worn saddle or nut. If it's just one note, it could be a worn saddle, nut, or worn fret. Or, your action might be set too low. In any case, take the guitar to a reputable guitar store.
How do you tell if a guitar is damaged?
#1 – Check the Neck and Headstock
A gap, even one the thickness of a business card, can indicate the need for repair. This is generally caused by the extreme tension of the strings. It can indicate either that the guitar is damaged or was built from inferior materials.