Tuning your Bass  
For tuning purposes a standard reference note, called concert pitch, has been set at A 440 Hz (Hertz). Here are the three basic physical factors that determine the pitch and tuning of a string:
  1. Tension  After stretching and re-tuning, place your thumb on the string just past the bridge and push the string down to get rid of any slight upward curvature of the string as it goes over the bridge. Do the same thing at the other end as the string leaves the post (tuning peg).
  2. Mass  Shortening a string raises its pitch and lengthening lowers its pitch.
  3. Length  The thicker the string (gauge) the lower its pitch and the thinner the string (gauge) the higher its pitch - for the same given tension.
Tuning a Guitar to Concert Pitch
This involves tuning the open strings to reference notes from another instrument (eg, a keyboard or guitar) that has already been tuned to concert pitch (A440). Tune your strings by using the method outlined below.
  1. Get a reference note from another instrument (eg, a keyboard or tuning fork).
  2. Always tune up and never down to a reference note. If a string is too high in pitch, take it down below the pitch of the note you're tuning to, stretch the string (see photo) and then tune up.
  3. Stretch each string by lifting it up 1-2cm (approx. ½") and pulling it from side to side by approximately 1.5cm (½"). The photo shows the bottom low E string being stretched.
  4. Repeat this process of stretching and fine tuning until each string doesn’t slip.
Always tune up and never down as this helps prevent the string from slipping.
New strings should always be stretched and re-tuned.
 
 
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