This paper proposes a technique that estimates the locations along the string of the plucking event and the magnetic pickup of an electric guitar based on the autocorrelation of the spectral peaks. To improve accuracy, a method is introduced to flatten the spectrum before applying the autocorrelation function to the spectral peaks. The minimum mean squared error between the autocorrelation of the observed data and the electric guitar model is found in order to estimate the model parameters. The accuracy of the algorithm is tested on various plucking positions on all open strings for each pickup configuration. The accuracy of the proposed method for various plucking dynamics and fret positions is also evaluated. The method yields accurate results: the average absolute errors of the pickup position and plucking point estimates for single pickups are 3.53 and 5.11 mm, respectively, and for mixed pickups are 8.47 and 9.95 mm, respectively. The model can reliably distinguish which pickup configuration is selected using the pickup position estimates. Moreover, the method is robust to changes in plucking dynamics and fret positions.
References
1.
M.
Karjalainen
, V.
Välimäki
, and Z.
Jánosy
, “Towards high-quality sound synthesis of the guitar and string instruments
,” in Proceedings of the International Computer Music Conference
(1993
), p. 56
.2.
M.
Laurson
, C.
Erkut
, V.
Välimäki
, and M.
Kuuskankare
, “Methods for modeling realistic playing in acoustic guitar synthesis
,” Comput. Music J.
25
(3
), 38
–49
(2001
).3.
C. R.
Sullivan
, “Extending the karplus-strong algorithm to synthesize electric guitar timbres with distortion and feedback
,” Comput. Music J.
14
(3
), 26
–37
(1990
).4.
N.
Lindroos
, H.
Penttinen
, and V.
Välimäki
, “Parametric electric guitar synthesis
,” Comput. Music J.
35
(3
), 18
–27
(2011
).5.
A.
Case
, A.
Roginska
, J.
Matthew
, and J.
Anderson
, “Electric guitar—A blank canvas for timbre and tone
,” J. Acoust. Soc. Am.
133
(5
), 3308
(2013
).6.
N. H.
Fletcher
, “Plucked strings—A review
,” Catgut Acoust. Soc. Newslett.
26
, 13
–17
(1976
).7.
R. C.
Paiva
, J.
Pakarinen
, and V.
Välimäki
, “Acoustics and modeling of pickups
,” J. Audio Eng. Soc.
60
(10
), 768
–782
(2012
).8.
F.
Germain
and G.
Evangelista
, “Synthesis of guitar by digital waveguides: Modeling the plectrum in the physical interaction of the player with the instrument
,” in IEEE Workshop on Applications of Signal Processing to Audio and Acoustics (WASPAA'09)
(2009
), pp. 25
–28
.9.
G.
Evangelista
and F.
Eckerholm
, “Player–instrument interaction models for digital waveguide synthesis of guitar: Touch and collisions
,” IEEE Trans. Audio, Speech, Lang. Process.
18
(4
), 822
–832
(2010
).10.
S.
Bilbao
and A.
Torin
, “Numerical modeling and sound synthesis for articulated string/fretboard interactions
,” J. Audio Eng. Soc.
63
(5
), 336
–347
(2015
).11.
J.
Abeßer
, H.
Lukashevich
, and G.
Schuller
, “Feature-based extraction of plucking and expression styles of the electric bass guitar
,” in IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP10)
(2010
), pp. 2290
–2293
.12.
A.
Paté
, J.-L.
Le Carrou
, and B.
Fabre
, “Predicting the decay time of solid body electric guitar tones
,” J. Acoust. Soc. Am.
135
(5
), 3045
–3055
(2014
).13.
C.
Erkut
, V.
Välimäki
, M.
Karjalainen
, and M.
Laurson
, “Extraction of physical and expressive parameters for model-based sound synthesis of the classical guitar
,” in 108th Audio Engineering Society Convention
(2000
), p. 17.14.
J.
Abeßer
, “Automatic string detection for bass guitar and electric guitar
,” in International Symposium on Computer Music Modeling and Retrieval
(2012
), pp. 333
–352
.15.
C.
Traube
and J. O.
Smith
, “Estimating the plucking point on a guitar string
,” in Proceedings of the COST G-6 Conference on Digital Audio Effects
(2000
), pp. 153
–158
.16.
C.
Traube
and P.
Depalle
, “Extraction of the excitation point location on a string using weighted least-square estimation of a comb filter delay
,” in Proceedings of the Conference on Digital Audio Effects (DAFx)
(2003
), pp. 188
–191
.17.
H.
Penttinen
and V.
Välimäki
, “A time-domain approach to estimating the plucking point of guitar tones obtained with an under-saddle pickup
,” Appl. Acoust.
65
(12
), 1207
–1220
(2004
).18.
Z.
Mohamad
, S.
Dixon
, and C.
Harte
, “Pickup position and plucking point estimation on an electric guitar
,” in IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP17)
(2017
), pp. 651
–655
.19.
Z.
Mohamad
, S.
Dixon
, and C.
Harte
, “Digitally moving an electric guitar pickup
,” in Proc. of the 18th Int. Conf. on Digital Audio Effects (DAFx-15)
(2015
), pp. 284
–291
.20.
N. G.
Horton
and T. R.
Moore
, “Modeling the magnetic pickup of an electric guitar
,” Am. J. Phys.
77
(2
), 144
–150
(2009
).21.
T. D.
Rossing
and G.
Caldersmith
, “Guitars and lutes
,” in The Science of String Instruments
, edited by T. D.
Rossing
(Springer
, New York
, 2010
), pp. 19
–45
.22.
J. D.
Tillman
, “Response effects of guitar pickup position and width
” (2002), available at http://www.till.com/articles/PickupMixing/index.html (Last viewed August 14, 2017
).23.
D. E.
Hall
and A.
Askenfelt
, “Piano string excitation v: Spectra for real hammers and strings
,” J. Acoust. Soc. Am.
83
(4
), 1627
–1638
(1988
).24.
P.
Masri
, “Computer modelling of sound for transformation and synthesis of musical signals
,” Ph.D. thesis, University of Bristol
, 1996
, pp. 137
–141
.25.
L.
Rabiner
, “On the use of autocorrelation analysis for pitch detection
,” IEEE Trans. Acoust., Speech, Signal Process.
25
(1
), 24
–33
(1977
).26.
H.
Fletcher
, “Normal vibration frequencies of a stiff piano string
,” J. Acoust. Soc. Am.
36
(1
), 203
–209
(1964
).27.
S.
Dixon
, M.
Mauch
, and D.
Tidhar
, “Estimation of harpsichord inharmonicity and temperament from musical recordings
,” J. Acoust. Soc. Am.
131
(1
), 878
–887
(2012
).28.
I.
Barbancho
, L. J.
Tardon
, S.
Sammartino
, and A. M.
Barbancho
, “Inharmonicity-based method for the automatic generation of guitar tablature
,” IEEE Trans. Audio, Speech, Lang. Process.
20
(6
), 1857
–1868
(2012
).29.
J. O.
Smith
, “Spectral audio signal processing”
(2011), available at https://ccrma.stanford.edu/∼jos/sasp/ (Last viewed August 14, 2017
).30.
K. A.
Legge
and N. H.
Fletcher
, “Nonlinear generation of missing modes on a vibrating string
,” J. Acoust. Soc. Am.
76
(1
), 5
–12
(1984
).31.
H.
Penttinen
, “Acoustic timbre enhancement of guitar pickup signals with digital filters
,” Master's thesis, Helsinki University of Technology
, 1996
, p. 8
.© 2017 Author(s).
2017
Author(s)
You do not currently have access to this content.