Thousands of backing tracks, fully transcribed

All the jam tracks you'd hunt for on YouTube, in one place — each one with its chord changes laid out for you in a clear format, plus the chord and scale charts to go with them.
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The Neck: Frets, Scale Length and the Truss Rod

Why frets sit where they sit, what scale length changes, and the steel bar hidden inside your neck.

The neck is where you choose notes, and the frets are what make a guitar a guitar rather than a violin. A fret is a shaped metal wire set into the fingerboard. You do not press the string onto the wood; you press it just behind a fret so the string rests on the fret's crown. That metal edge becomes the new end of the vibrating string, which is why fretted notes are consistent — the pitch comes from the fret's position, not from exactly where your finger landed.

Close-up along an electric guitar fingerboard showing metal frets set into dark rosewood, pale trapezoid position markers and six strings
Frets set into the fingerboard, with position markers inlaid to help you find your place. The strings sit on the crowns of the frets, not on the wood. Photo: Daniil Ulanov, CC BY 2.0

The spacing is not arbitrary and it is not evenly spread. Each fret sits closer to the next than the last, following a fixed ratio: every fret shortens the remaining string by about 5.6 percent, which is a semitone in equal temperament. Luthiers used to work it out as the rule of eighteen — measure the remaining length, divide by roughly 17.8, and that is where the next fret goes.

The consequence you can hear is at the twelfth fret. Twelve semitones is an octave, and an octave means exactly half the string length, so the twelfth fret sits precisely halfway between the nut and the saddle. Play this and listen.

The twelfth fret is the halfway point

Pluck the open sixth string, then the same string at the twelfth fret. Same note, one octave higher, because you just halved the string.

e
B
G
D
A
E
-----------------|
-----------------|
-----------------|
-----------------|
-----------------|
--0-----------12-|

The full length between nut and saddle is the scale length, and different makers chose different ones. Fender settled on 25.5 inches, Gibson on 24.75. It is a small difference with real consequences: the longer scale needs more tension to reach the same pitch, so it feels tighter under the fingers and sounds a little brighter and tighter in the low end. The shorter scale feels slinkier and bends more easily. Neither is better; they just feel different, and players develop strong preferences.

Inside the neck, invisibly, is a steel rod. Six steel strings pull the neck into a forward bow, and wood moves with humidity and season besides. Gibson patented the adjustable truss rod in the early 1920s, and it changed what necks could be: a rod that counteracts string pull lets a neck be slim and still stable. Turn its nut and the neck bends very slightly, setting the amount of relief — the tiny amount of forward curve a neck needs so strings do not buzz.

The truss rod adjustment nut recessed in a hole at the end of an acoustic guitar's neck, seen from inside the soundhole
A truss rod nut, reached through the soundhole on this acoustic. On many electrics it is at the headstock instead, sometimes under a small cover. It is an adjustment, not a tuning control — small turns, and when in doubt leave it to a tech. Photo: Gothick, CC BY-SA 4.0

Where the neck meets the body matters too. Gibson traditionally glues the neck in, a set neck. Fender bolted it on, which in 1950 was a manufacturing decision — necks could be made separately and swapped if damaged — and is still standard. Some guitars run a single piece of wood the whole length, a neck-through. Players argue endlessly about the tonal differences; what is not arguable is that a bolt-on is far easier to repair.

One last neck part, and it is removable: the capo. A capo clamps across the strings and becomes a temporary nut, shortening every string equally. It does not change the shapes you play, it changes what key those shapes sound in.

A black spring clamp capo fastened across the strings of an electric guitar neck at a fret
A capo at work. Everything above it is now the vibrating length; the shapes you know keep working, in a higher key. Photo via Wikimedia Commons, CC BY-SA 3.0

Capo Transposer

Work out what a capo does to your key: put the capo at a fret and see which chord shapes produce which chords.

Shapes You Know
G
The chord shapes you’re comfortable playing — used by both panels below.
If I capo here, what key do I get?
Fret 2
G shapes, capo at fret 2, sounds in
A
I want to play in this key — where do I capo?
A
To sound in A using G shapes, capo at
Fret 2
How capos workA capo acts like a moveable nut — it shortens the strings so your open-position shapes ring out higher than they normally would, exactly one semitone per fret. So if you know G-shape chords and capo at fret 2, your hands are still playing the same G shapes, but the chord that actually sounds is A. That’s the whole trick: same shapes, different key, just by sliding the capo up or down the neck.

Fretboard Note Trainer

And to get the fretboard itself under your fingers, drill note names against the clock.

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