Pierwszy akord 'A Hard Days Night' (ang.).pdf

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Mathematics, Physics and A Hard Day’s Night
Jason I. Brown, Dalhousie University
Abstract
Version 1: G C F Bb D G (a favorite by its
ease of play; just play a barre chord at the
third fret).
In this article we shall use mathematics
and the physics of sound to unravel one of
the mysteries of rock ’n’ roll – how did the
Beatles play the opening chord of A Hard
Day’s Night ? The song may never sound the
same to you again.
1 Introduction
It was forty years ago that the Beatles ushered in a
new era in pop music with the opening of A Hard
Day’s Night . The importance of the opening chord
was clearly apparent to the Beatles. In The Com-
plete Beatles Recording Sessions [3], author Mark
Lewisohn quotes the Beatles’ producer, George Mar-
tin, “We knew it would open both the lm and the
soundtrack LP, so we wanted a particularly strong
and eective beginning. The strident guitar chord
was the perfect launch.” This seemed to close the
discussion about the origin of the chord but should
it have?
Many a guitarist (whether professional or ama-
teur) has tried to reproduce the chord, but the voic-
ing of the chord has remained a subject of much dis-
cussion over the past 40 years. If you browse musi-
cal transcriptions for the chord, you will come across
three common ones (note that guitar parts are scored
as usual an octave up from where they sound):
Version 2: G D F C D G (another favorite, and
one that often appears on Internet sites as the
“one” that George Harrison (GH) played).
1
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Version 3: This one has George, John Lennon
(JL) and Paul McCartney (PM) playing, with
George (on his twelve string electric) playing G
D G C D G, slightly dierent than in version
2, while John plays D G C G and Paul plays D
on his bass (this is the transcription from [1]).
2 Musical Forensics
We need to discuss briey the physics and mathe-
matics of sound (see [5, 2] for more details). Pure
tones have a frequency, which corresponds to its
pitch, and an amplitude, which corresponds roughly
(but not exactly) to the loudness of the tone, and are
modelled mathematically by sine and cosine func-
tions. All sounds are made up of pure tones, which
add together to give you complex tones and chords
(that is, the functions of the latter are linear com-
binations of the functions for the pure tones). A
single note sounded on an instrument is made up
of a fundamental (main) pure tone plus other tones,
called harmonics, whose frequencies are multiples of
the fundamental tone’s frequency. All of the ampli-
tudes are added together in this “mix” that we hear.
When a sound is digitized for a CD, the amplitude is
sampled 44,100 times every second. What is hidden
in the process of recording music are the individ-
ual frequencies, and how they were played. Fourier
Transforms can be used to dissassemble the sampled
amplitudes into the original frequencies.
After the song A Hard Day’s Night was opened
in a sound editing program on a computer, a seg-
ment of approximately one second was selected in
the middle of the chord. The sound was saved as a
le, and using some Mathematica subroutines from
[2, chapter 14] a Fourier Transform was run on the
list of data. There were 29,375 frequencies present,
which included not only the notes being struck, but
also harmonics, as well as any other frequencies that
might have arisen during the recording.
We are after the loudest notes, as these corre-
spond to the fundamental notes being struck (though
there will probably be some of the louder harmon-
ics present, along with possibly some other loud rat-
tles). A threshhold was chosen which kept the sound
faithful to the original. The table shows the 48 fre-
quencies with amplitude 0 . 02 or larger.
Is there any way to tell which of these three ver-
sions is the right one? Mathematics will help direct
us to the answer.
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Freq. (Hz) Ampl.
Freq. (Hz) Ampl.
Freq. (Hz) Ampl.
Freq. (Hz) Ampl.
110.34
0.0600967 299.494
0.0298296 1050.86
0.0687151 2368.93
0.0221358
145.619
0.025485 392.57
0.0309716 1185.97
0.0372155 2371.19
0.0212846
148.621
0.0264278 438.358
0.0286329 1286.55
0.0231789 2371.94
0.0436633
149.372
0.0656018 524.678
0.0680974 1314.32
0.03819
2372.69
0.036042
150.123
0.175149 587.73
0.020613 1320.33
0.0223535 2637.65
0.0261839
174.142
0.0275547 588.48
0.0310337 1321.08
0.0494908 2638.4
0.0237794
174.893
0.0380282 589.231
0.0231753 1488.47
0.0241328 2754.
0.020001
175.643
0.0407103 785.141
0.0323532 1632.58
0.0205742 2763.76
0.0493617
195.159
0.0405164 786.642
0.0251928 1750.43
0.0234704 3083.52
0.0332062
218.428
0.0448308 787.393
0.0268553 2359.93
0.0366079 3147.32
0.0293723
261.964
0.0302402 960.784
0.0228509 2367.43
0.0267098 3148.07
0.0418507
262.714
0.0234502 981.801
0.02242
2368.18
0.0755327 3158.58
0.0285631
The frequencies need to be converted to notes,
so choosing the reference note A 220 Hz, the fre-
quencies were converted to the number of semitones
above or below A 220 (by applying the function
f ( x ) = 12 log 2 ( x/ 220)). Here is the list of semitones
(we see that some of the instruments could have been
better tuned as not all of the numbers are close to
their nearest integer):
how the notes were played we’ll need to make some
deductions.
Some of the notes (especially in the higher range)
must be harmonics, as they are well beyond what
instruments can play. In fact, the range of a guitar
is from E2 to about E6 and the bass guitar from
E1 to about D4. Notes could have arisen on either
George Harrison’s or John Lennon’s guitar or Paul’s
bass. The analysis now shows why the three well
known transcriptions of the opening chord must all
be wrong: each has a low G2 being played, but this
note is denitely missing.
It is well known that for the album A Hard Day’s
Night , George used a 12 string guitar and its sound
can denitely be heard on the solo in A Hard Day’s
Night . Thus it seems safe to assume George used
this guitar on the opening chord as well. The twelve
string guitar has each string doubled, with the bot-
tom four in octaves, so the strings are, from lowest
to highest, E2 E3 A2 A3 D3 D4 G3 G4 B3 B3 E4 E4.
It seems reasonable that notes on strings of roughly
the same thickness struck on one instrument would
be roughly of the same amplitude. Looking back at
the frequencies and their amplitudes, we see that one
D3 is extra loud, with an amplitude of 0.175. This
is taken as a bass note from Paul’s Hofner bass (no
other single frequency is nearly as loud).
Now A2 and A3 can be paired o, both likely
coming from George’s 12 string (a nice open pair of
strings). But even with one of the D3’s accounted
for on Paul’s bass, what about the other three D3’s?
11 . 9466, 7 . 14367, 6 . 79035, 6 . 70313,
6 . 61635, 4 . 04686, 3 . 97239, 3 . 89825,
2 . 07421, 0 . 124124, 3.02237, 3.07191, 5.34031,
10.0254, 11.9353, 15.0472, 17.0118, 17.0339, 17.056,
22.0254, 22.0584, 22.075, 25.5205, 25.8951, 27.0719,
29.1659, 30.5752, 30.9449, 31.0238, 31.0337, 33.099,
34.699, 35.9056, 41.078, 41.133, 41.1385, 41.1439,
41.1604, 41.1659, 41.1714, 43.0042, 43.0091, 43.7514,
43.8127, 45.708, 46.0626, 46.0667, 46.1244
In musical circles, middle C is written as C4, with
the second number indicating the octave, so A 220
Hz is written as A3. Here are the frequencies above
rounded to the nearest semitones:
A2, D3, D3, D3, D3, F3, F3, F3, G3, A3, C4, C4,
D4, G4, A4, C5, D5, D5, D5, G5, G5, G5, B5, B5,
C6, D6, E6, E6, E6, E6, F#6, G#6, A6, D7, D7,
D7, D7, D7, D7, D7, E7, E7, F7, F7, G7, G7, G7,
G7
Many of the notes appear in the various versions
of “the chord”. But to argue what was played and
3
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Only one can come from George’s 12 string, and even
if John played another one on his six string, there’s
still another to account for. There is no evidence
that any guitar was multitracked, at least on this
opening chord. The two F3s create a much bigger
problem. For no matter how George plays an F3 on
his 12 string, an F4 should be heard as well, and
there is no F4 at all present!
A hidden assumption came to the fore. Beat-
les’ record producer, George Martin, is known to
have doubled on piano George Harrison’s solo on
the track. Could “the chord” be part piano? Pi-
anos have three strings for every note; a hammer
strikes all three at the same time to produce a sound.
That solved the problem of the three F3’s: all could
have come from a piano playing F3. Note that the
frequencies of the three F3s were slightly dierent,
but each string on a piano is individually tuned and
is likely to be slightly o from one another in the
“triple.”
But what about the three left over D3’s? If all be-
longed to a single piano note, then where would the
single D4 come from? Not from George Harrison’s
guitar (as a D3 or another D4 would be present) and
not from George Martin’s piano (as otherwise there
would be three D4’s present). However, the bottom
ten pitches on a piano are single strings which change
to pairs of strings, and around C3 they change to the
usual triples of strings. But indeed there are some
grand pianos (of medium length) for which the break
occurs right after D3. This implied that two of the
D3s were played on the piano.
What George Harrison played on his 12 string
was nothing like any of the transcriptions: he played
A2 A3 D3 D4 G3 G4 C4 C4, most likely on string
sets 2 through 5 – eight strings with six open strings
in total; (for a great chiming eect). George Martin
(GM) played D3 F3 D5 G5 E6 on the piano. The
other notes are fairly high and could be attributed
to harmonics of these notes, except that there is a
loud C5, which could have been played by John high
up on his six string. There is also one extra E6 un-
accounted for, which is taken as a harmonic.
3 The End
The notes played on the piano interweave well with
the notes on the 12 string, starting a bit higher (at
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D3) from the lowest note played on the guitar and
ending higher (at E6). The amplitudes show why the
piano is so well hidden; it is mixed perfectly, with
amplitudes almost identical to those of the higher
strings played on Harrison’s guitar.
In All You Need is Ears [4], George Martin makes
a point of saying “it shouldn’t be expected that peo-
ple are necessarily doing what they appear to be
doing on records” and likens recording to lmmak-
ing, where all sorts of eects are carried out in the
background in order to create illusions. We see that
sometimes mathematics can unravel the best mys-
teries.
References
[1] T. Fujita, Y. Hagino, H. Kubo and G. Sato, The
Beatles Complete Scores , Hal Leonard, Milwau-
kee, 1993.
[2] T.W. Gray and J. Glynn, Exploring Mathe-
matics with Mathematica , Addison Wesley, New
York, 1991.
[3] M. Lewisohn, The Complete Beatles Recording
Sessions , Doubleday, Toronto, 1988.
Acknowledgements
[4] G. Martin, All You Need Is Ears , St. Martins’
Press, New York, 1979.
This article was partially supported by a grant
from the Natural Sciences and Engineering Research
Council of Canada.
[5] J.S. Rigden, Physics and the Sound of Music ,
Wiley, New York, 1977, pg. 71.
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