Watch the Description of the Bass online guitar lesson by John Goldsby from Upright Bass Handbook

So what's this thing called? There are a lot of names for this instrument: upright bass, double bass, string bass, bass viol, bass violin, contrabass, bass fiddle, bull fiddle, acoustic bass, standup bass, doghouse . . . the tree . . .but I prefer to call it a double bass--like its name in the orchestra--or if I'm also switching back and forth on electric bass guitar, I might refer to this instrument as the acoustic bass. It's convenient if you're doubling on both instruments to think "electric or acoustic." Upright bass is also a common name for this instrument, as in "The Upright Bass Handbook."

Let's look at the parts of the bass:
  1. Scroll: Starting with possibly the least important part of the instrument; at the top of the bass, we see the scroll. The scroll is ornamental, but a nicely-carved scroll shows that care went into building the instrument.
  2. Peg Box: At the top of the bass, the strings go into the peg box, and they're wound around the tuning machine posts.
  3. Tuning Keys: The tuning pegs might also be called tuning keys, or tuning machines. These are similar to what you see on an electric bass.
  4. Nut: The nut sits at the top end of the fingerboard. This is a small piece of hardwood, like ebony. The strings travel through slots cut into the nut. It's important to have a nut that that is cut to keep the strings comfortably low, but not so low that they buzz.
  5. Neck: The neck is usually made of maple or some kind of hard wood. The neck is fitted and glued into the body of the bass with animal hide glue. Double bass luthiers never use any kind of white or permanent bonding glue.
  6. Fingerboard: The fingerboard is glued onto the neck with animal hide glue. The fingerboard is planed with a slight contour or concave relief, so the strings don't buzz.
  7. Heel of the Neck: The heel of the neck is an important landmark on the double bass. This is where the bottom of the neck flames at the point where it attaches to the body of the bass. This landmark can help you find the notes in the middle of the neck and the notes going into the high positions.
  8. Top/Table: The top of the bass--sometimes called the table or belly--is where most of the sound is produced. The top is defined by the shoulders, the bouts--the upper bout, the C bout, and the lower bout--and the F-holes. The F-holes allow sound to emanate from the body of the instrument. A microphone to amplify or record the bass is best not placed directly in front of the F-hole. Put a microphone in front of the bridge, or towards the foot of the bridge.
  9. Bridge: The bridge is another important sound-producing component of the bass. The bridge holds the strings, and transmits sound from the strings to the body of the instrument. Many bridges have adjusters built in, so you can easily change the string height above the fingerboard. I usually keep my strings at about 7 millimeters on the G string, 9 millimeters on the E string, measured from the end of the fingerboard to the bottom side of the string. Most pickup systems take their signal from the bridge. Some clamp onto the bridge, go under the feet of the bridge, are built into the bridge adjusters, or are built into the bridge. Most pickups (transducers) will attach to the bridge of the bass, and connect to an amplifier to make the acoustic sound of the bass louder.
  10. Mensur/String Length: The string length (also called the mensur) is the measurement between the nut and the bridge--the length of the vibrating part of the string. Most double basses have a string length of between 40"-42" (ca. 102-108 cm). Compare that to the typical electric bass with its string length of 34" (ca/ 86 cm)!
  11. Tailpiece: The tailpiece holds the strings to the bottom of the bass. The tailpiece is anchored with an endpin wire or tailpiece wire, which travels over the saddle at the bottom of the bass.
  12. Endpin: The endpin is usually adjustable, so you can put the bass at the correct height for your size. Experiment with the endpin height in order to find a good playing position for your body type. Remember that the nut at the top of the fingerboard should be about at your eye level.
  13. Inside the Bass: The top is supported inside the bass on the E-string side with a bass bar, and on the G-string side with a soundpost. There are braces inside the bass for extra structural support.
  14. Soundpost: The soundpost is another extremely important sound-transmitting component. The soundpost is positioned inside the bass, between the top of the back, just near the foot of the bridge on the G-string side. The soundpost transmits sound from the top of the bass to the back, and can be adjusted for different sound qualities. You should have your soundpost setup by a professional luthier. If you ever change your bass strings, only change one string at a time, otherwise your soundpost might drop inside the bass!
  15. Braces: Inside the bass, there are usually braces strengthening the back of the instrument. The whole instrument is glued together with animal hide glue. If you have problems or questions about the setup of your bass, go to a professional violin or bass shop. A well set up instrument will make all the difference in your sound and in your ability to get around the bass.
  16. Bass Bar: The bass bar is an important piece of wood inside the body of the instrument, attached to the top. You can see a small part of the bass bar if you look inside the F-hole on the E-string side. The bass bar runs the length of the top, and is meticulously fitted to the shape of the top. This piece of wood helps support the top on the E-string side (the soundpost sits on the G-string side) and transmit sound from the bridge through the top of the instrument.