TOOL
Capo
Clamps the strings at a fret — and shows up any setup problem.
| Types | Spring, screw, lever, yoke |
|---|---|
| Radius | Must match the fretboard radius |
| Pad | Rubber or silicone, non-marking |
| Adjustment | Fixed (spring) or variable (screw / lever) |
| Reach | Some suit wider necks and twelve-strings |
| Weight | A heavy capo on a light neck changes the balance |
| Tension | Just enough to stop buzzing |
|---|---|
| Position | Close behind the fret, not in the middle |
| Tuning | Retune after fitting; check the octave |
| Radius match | A mismatched capo buzzes the middle strings |
| Finish | Check the pad for embedded grit before use |
| Price band | Low to moderate |
A capo clamps across the strings at a chosen fret so the guitar can be played in a different key with the same shapes. It is also an accidental diagnostic tool: a capo that pulls the guitar sharp is telling you the nut or the action is wrong.
Spring capos are fast but apply a fixed, often excessive force. Screw and lever capos let you set the tension just high enough to stop buzzing, which is what keeps the instrument in tune with the capo on.
At this stage
A capo is used during setup to check the frets above the clamped position, and it will expose a high fret that is invisible without it.
Suits these instruments
- All guitars
Works with
- Strings
- String winder
- Action gauge
- Truss rod
- Check the pad for grit before clamping. A single grain of sand under a capo dents a fret.
- Do not force a capo that does not fit the neck width; it damages the binding and the fingerboard edge.
Working notes
- Place the capo just behind the fret, not halfway between two frets.
- If the guitar goes sharp with the capo on, the tension is too high — use an adjustable one.
- Match the capo radius to the board. A flat capo on a 184 mm radius board will buzz.
- Store it off the instrument so it does not leave a mark on the neck over time.
Related
Action gauge
Reads string height at the twelfth fret without arguing about it.
Feeler gauge
The only honest way to measure relief and nut height.
Notched straightedge
Reads the fretboard itself, not the tops of the frets.
String winder
Turns a fifteen-minute string change into five.