Why Clamp a Guitar Instead of Playing Different Chords? Keep the Shapes

The device presses all the strings down at one position along the neck, shortening every string by the same proportion, which raises each by the same interval and leaves the tuning relationships between them unchanged. Everything a player knew before still works, with each shape now producing a chord a fixed number of semitones higher. Placing it at the second position turns a shape that sounded in one key into the same shape sounding two semitones higher. That is the entire mechanism, and it explains both what the device makes easy and what it does not change, since the relationships between the chords a player uses are exactly as they were.

Transposing for a singer is only one of several reasons and not the most interesting:

• •Matching a singer's range without relearning the song in a difficult key
• •Keeping the open strings, which ring and sustain in a way fretted notes do not
• •Playing in keys where every chord would otherwise need a barre
• •Brightening the tone, since a shortened string sounds thinner and more cutting
• •Allowing two guitarists to play the same chords at different pitches
• •Reaching chord voicings that are impossible to finger otherwise

The tonal argument is the one non-players miss, and it concerns what an open string does that a fretted one cannot. A string stopped by a finger is damped by the flesh, decays faster and sounds slightly duller, while an open string vibrates between two hard points and rings longer and brighter. Chord shapes using open strings therefore have a characteristic resonance, and much of the sound of folk and popular guitar playing depends on it. Playing the same chords in a key requiring barres loses that entirely. The clamp preserves it in any key, which is why a recording may use one on every track and why the choice is made for sound rather than for ease.

The device causes specific tuning problems and knowing them saves a great deal of confusion. Clamping too hard pulls the strings sideways and sharp, which puts the instrument out of tune with itself in a way that sounds like a fault in the guitar rather than in the clamp, so the pressure should be the least that stops buzzing. Placing it in the middle of the space between frets rather than just behind the higher one produces the same problem. A neck with a curved fingerboard needs a device curved to match, since a straight bar presses the outer strings harder than the inner ones. And the instrument should be tuned after fitting rather than before, because the fitting itself changes the tuning slightly whatever care is taken.

A persistent criticism holds that using one is a crutch that lets players avoid learning the fretboard properly, and the criticism contains something true and misses the point. It is true that a player who only ever uses one position of shapes has learned less than a player who can play in any key without help, and that relying on it to avoid barre chords delays acquiring a necessary technique. It is also true that classical guitarists rarely use one and that orchestral instruments have no equivalent. Against that, the device is used constantly by professionals who plainly can play anywhere on the neck, for the tonal reasons above, and notable recordings across every popular genre were made with one fitted.

Clamping all the strings at one position raises them equally, so every shape still works and now sounds higher, which moves a song into a new key without relearning it. The most substantial reason to use one is tonal rather than practical, since open strings ring brighter and longer than fretted ones and that resonance is central to a great deal of guitar playing. The criticism that it avoids learning the neck is partly fair and does not explain professional use.