[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:07.01,0:00:10.78,Default,,0000,0000,0000,,Hendrix, Cobain and Page.
Dialogue: 0,0:00:10.78,0:00:12.35,Default,,0000,0000,0000,,They can all shred,
Dialogue: 0,0:00:12.35,0:00:16.24,Default,,0000,0000,0000,,but how exactly do the iconic \Ncontraptions in their hands
Dialogue: 0,0:00:16.24,0:00:21.69,Default,,0000,0000,0000,,produce notes, rhythm, melody and music.
Dialogue: 0,0:00:21.69,0:00:26.60,Default,,0000,0000,0000,,When you pluck a guitar string, you create\Na vibration called a standing wave.
Dialogue: 0,0:00:26.60,0:00:30.53,Default,,0000,0000,0000,,Some points on the string, called nodes,\Ndon't move at all,
Dialogue: 0,0:00:30.53,0:00:35.18,Default,,0000,0000,0000,,while other points, anti-nodes, \Noscillate back and forth.
Dialogue: 0,0:00:35.18,0:00:39.58,Default,,0000,0000,0000,,The vibration translates through the neck\Nand bridge to the guitar's body,
Dialogue: 0,0:00:39.58,0:00:42.43,Default,,0000,0000,0000,,where the thin and flexible wood vibrates,
Dialogue: 0,0:00:42.43,0:00:46.62,Default,,0000,0000,0000,,jostling the surrounding air molecules\Ntogether and apart.
Dialogue: 0,0:00:46.62,0:00:49.73,Default,,0000,0000,0000,,These sequential compressions\Ncreate sound waves,
Dialogue: 0,0:00:49.73,0:00:53.93,Default,,0000,0000,0000,,and the ones inside the guitar\Nmostly escape through the hole.
Dialogue: 0,0:00:53.93,0:00:56.22,Default,,0000,0000,0000,,They eventually propagate to your ear,
Dialogue: 0,0:00:56.22,0:00:58.79,Default,,0000,0000,0000,,which translates them into\Nelectrical impulses
Dialogue: 0,0:00:58.79,0:01:01.92,Default,,0000,0000,0000,,that your brain interprets as sound.
Dialogue: 0,0:01:01.92,0:01:06.48,Default,,0000,0000,0000,,The pitch of that sound depends on\Nthe frequency of the compressions.
Dialogue: 0,0:01:06.48,0:01:10.98,Default,,0000,0000,0000,,A quickly vibrating string will cause\Na lot of compressions close together,
Dialogue: 0,0:01:10.98,0:01:12.55,Default,,0000,0000,0000,,making a high-pitched sound,
Dialogue: 0,0:01:12.55,0:01:16.42,Default,,0000,0000,0000,,and a slow vibration \Nproduces a low-pitched sound.
Dialogue: 0,0:01:16.42,0:01:19.68,Default,,0000,0000,0000,,Four things affect the frequency\Nof a vibrating string:
Dialogue: 0,0:01:19.68,0:01:24.21,Default,,0000,0000,0000,,the length, the tension,\Nthe density and the thickness.
Dialogue: 0,0:01:24.21,0:01:27.03,Default,,0000,0000,0000,,Typical guitar strings \Nare all the same length,
Dialogue: 0,0:01:27.03,0:01:31.52,Default,,0000,0000,0000,,and have similar tension,\Nbut vary in thickness and density.
Dialogue: 0,0:01:31.52,0:01:35.99,Default,,0000,0000,0000,,Thicker strings vibrate more slowly,\Nproducing lower notes.
Dialogue: 0,0:01:35.99,0:01:37.99,Default,,0000,0000,0000,,Each time you pluck a string,
Dialogue: 0,0:01:37.99,0:01:40.75,Default,,0000,0000,0000,,you actually create \Nseveral standing waves.
Dialogue: 0,0:01:40.75,0:01:44.98,Default,,0000,0000,0000,,There's the first fundamental wave,\Nwhich determines the pitch of the note,
Dialogue: 0,0:01:44.98,0:01:47.53,Default,,0000,0000,0000,,but there are also waves\Ncalled overtones,
Dialogue: 0,0:01:47.53,0:01:51.34,Default,,0000,0000,0000,,whose frequencies \Nare multiples of the first one.
Dialogue: 0,0:01:51.34,0:01:57.06,Default,,0000,0000,0000,,All these standing waves combine\Nto form a complex wave with a rich sound.
Dialogue: 0,0:01:57.06,0:02:01.45,Default,,0000,0000,0000,,Changing the way you pluck the string\Naffects which overtones you get.
Dialogue: 0,0:02:01.45,0:02:03.18,Default,,0000,0000,0000,,If you pluck it near the middle,
Dialogue: 0,0:02:03.18,0:02:07.10,Default,,0000,0000,0000,,you get mainly the fundamental\Nand the odd multiple overtones,
Dialogue: 0,0:02:07.10,0:02:10.08,Default,,0000,0000,0000,,which have anti-nodes\Nin the middle of the string.
Dialogue: 0,0:02:10.08,0:02:14.36,Default,,0000,0000,0000,,If you pluck it near the bridge,\Nyou get mainly even multiple overtones
Dialogue: 0,0:02:14.36,0:02:16.41,Default,,0000,0000,0000,,and a twangier sound.
Dialogue: 0,0:02:16.41,0:02:22.26,Default,,0000,0000,0000,,The familiar Western scale is based on\Nthe overtone series of a vibrating string.
Dialogue: 0,0:02:22.26,0:02:27.26,Default,,0000,0000,0000,,When we hear one note played with another\Nthat has exactly twice its frequency,
Dialogue: 0,0:02:27.26,0:02:29.20,Default,,0000,0000,0000,,its first overtone,
Dialogue: 0,0:02:29.20,0:02:33.20,Default,,0000,0000,0000,,they sound so harmonious\Nthat we assign them the same letter,
Dialogue: 0,0:02:33.20,0:02:36.93,Default,,0000,0000,0000,,and define the difference between them\Nas an octave.
Dialogue: 0,0:02:36.93,0:02:40.12,Default,,0000,0000,0000,,The rest of the scale \Nis squeezed into that octave
Dialogue: 0,0:02:40.12,0:02:42.10,Default,,0000,0000,0000,,divided into twelve half steps\N
Dialogue: 0,0:02:42.10,0:02:48.04,Default,,0000,0000,0000,,whose frequency is each 2^(1/12)\Nhigher than the one before.
Dialogue: 0,0:02:48.04,0:02:51.29,Default,,0000,0000,0000,,That factor determines the fret spacing.
Dialogue: 0,0:02:51.29,0:02:57.12,Default,,0000,0000,0000,,Each fret divides the string's\Nremaining length by 2^(1/12),
Dialogue: 0,0:02:57.12,0:03:00.58,Default,,0000,0000,0000,,making the frequencies \Nincrease by half steps.
Dialogue: 0,0:03:00.58,0:03:02.60,Default,,0000,0000,0000,,Fretless instruments, like violins,
Dialogue: 0,0:03:02.60,0:03:06.93,Default,,0000,0000,0000,,make it easier to produce the infinite\Nfrequencies between each note,
Dialogue: 0,0:03:06.93,0:03:10.52,Default,,0000,0000,0000,,but add to the challenge \Nof playing intune.
Dialogue: 0,0:03:10.52,0:03:12.58,Default,,0000,0000,0000,,The number of strings and their tuning
Dialogue: 0,0:03:12.58,0:03:15.79,Default,,0000,0000,0000,,are custom tailored \Nto the chords we like to play
Dialogue: 0,0:03:15.79,0:03:17.98,Default,,0000,0000,0000,,and the physiology of our hands.
Dialogue: 0,0:03:17.98,0:03:20.86,Default,,0000,0000,0000,,Guitar shapes and materials can also vary,
Dialogue: 0,0:03:20.86,0:03:24.53,Default,,0000,0000,0000,,and both change the nature \Nand sound of the vibrations.
Dialogue: 0,0:03:24.53,0:03:27.21,Default,,0000,0000,0000,,Playing two or more \Nstrings at the same time
Dialogue: 0,0:03:27.21,0:03:32.20,Default,,0000,0000,0000,,allows you to create new wave patterns\Nlike chords and other sound effects.
Dialogue: 0,0:03:32.20,0:03:36.28,Default,,0000,0000,0000,,For example, when you play two notes\Nwhose frequencies are close together,
Dialogue: 0,0:03:36.28,0:03:41.60,Default,,0000,0000,0000,,they add together to create a sound wave\Nwhose amplitude rises and falls,
Dialogue: 0,0:03:41.60,0:03:46.50,Default,,0000,0000,0000,,producing a throbbing effect,\Nwhich guitarists call the beats.
Dialogue: 0,0:03:46.50,0:03:49.51,Default,,0000,0000,0000,,And electric guitars give you \Neven more to play with.
Dialogue: 0,0:03:49.51,0:03:51.69,Default,,0000,0000,0000,,The vibrations still start in the strings,
Dialogue: 0,0:03:51.69,0:03:55.93,Default,,0000,0000,0000,,but then they're translated \Ninto electrical signals by pickups
Dialogue: 0,0:03:55.93,0:03:59.08,Default,,0000,0000,0000,,and transmitted to speakers \Nthat create the sound waves.
Dialogue: 0,0:03:59.08,0:04:00.91,Default,,0000,0000,0000,,Between the pickups and speakers,
Dialogue: 0,0:04:00.91,0:04:04.68,Default,,0000,0000,0000,,it's possible to process \Nthe wave in various ways,
Dialogue: 0,0:04:04.68,0:04:11.76,Default,,0000,0000,0000,,to create effects like distortion,\Noverdrive, wah-wah, delay and flanger.
Dialogue: 0,0:04:11.76,0:04:16.14,Default,,0000,0000,0000,,And lest you think that the physics \Nof music is only useful for entertainment,
Dialogue: 0,0:04:16.14,0:04:18.06,Default,,0000,0000,0000,,consider this.
Dialogue: 0,0:04:18.06,0:04:20.82,Default,,0000,0000,0000,,Some physicists think that everything\Nin the universe
Dialogue: 0,0:04:20.82,0:04:26.89,Default,,0000,0000,0000,,is created by the harmonic series\Nof very tiny, very tense strings.
Dialogue: 0,0:04:26.89,0:04:29.47,Default,,0000,0000,0000,,So might our entire reality
Dialogue: 0,0:04:29.47,0:04:33.77,Default,,0000,0000,0000,,be the extended solo \Nof some cosmic Jimi Hendrix?
Dialogue: 0,0:04:33.77,0:04:39.12,Default,,0000,0000,0000,,Clearly, there's a lot more to strings\Nthan meets the ear.