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Spécial « Congrès Acoustics 2012 »
Acoustical and musical properties of the Deskford carnyx reconstruction
In 2004 an archaeological dig at Tintignac in France unco-
vered a cache of metal objects including parts of seve-
ral carnyxes. It has recently proved possible to assemble
from reconstructions of these parts a complete instrument,
which is the subject of another paper at this conference [3].
This exciting development provides a stimulus for a recon-
sideration of the decisions made in reconstructing the
Deskford carnyx. Quite apart from the historical and
archaeological interest in the carnyx, the experience of
John Kenny in over eighteen years of playing the instru-
ment, writing music for it and commissioning works by
other composers has confirmed his view that the Deskford
reconstruction is a wind instrument with a unique presence
and voice. The present study attempts to relate scientific
measurements of the acoustical properties of this instru-
ment to specific aspects of its musical behaviour.
Fig. 1 : The Deskford carnyx reconstruction, sounded by an
artificial mouth in the Musical Acoustics Laboratory at the
University of Edinburgh
La reproduction du carynx de Deskford, animé par
une bouche artificielle au Laboratoire d’acoustique
musicale de l’université d’Edimbourgh
Bore profile of Deskford carnyx reconstruction
The length of the reconstruction from the mouthpiece to
the point at which the tube enters the head is just over
1.6 m. In the original prototype most of the main bore was
cylindrical. To improve the harmonicity of the acoustical
resonances it was suggested that this bore was made
conical; practical considerations led to the compromise
that the main tube expanded slightly in a series of steps,
as shown in Figure 3. Various designs of mouthpiece were
constructed. Playing experience led John Kenny to choose
a design with a minimal bore constriction (’throat’); the
bore profile in Figure 3 includes this mouthpiece.
Physical measurements of the bore of the completed instru-
ment were complemented by a bore reconstruction using
Acoustic Pulse Reflectometry (APR), shown in Figure 4. For
this measurement the mouthpiece section was removed
and replaced by a cylindrical connector 60mm shorter. The
interior of the head is a complex structure with a movea-
ble jaw and a large sprung wooden tongue (see Figure 2).
From the APR curve it can be deduced that the termina-
ting impedance presented to the internal air column by
the head is similar to that of a rapidly flaring bell.
Fig. 2 : Detail of the Deskford carnyx reconstruction, showing the
head and throat
Détail de la reproduction du carynx de Deskford
représentant la tête et le cou
Fig. 3 : Measured internal bore profile of carnyx reconstruction,
from integral mouthpiece to junction with head
Mesure du profil d’alésage interne de la reproduction du
carnyx, de l’embout buccal à la jonction avec la tête
Fig. 4 : Internal bore profile of carnyx, reconstructed using
acoustics pulse reflectometry
Profil d’alésage interne du carynx, reproduit
en utilisant la réflectrométrie acoustique
