François-Bernard Mâche's interpretation of Sopiana for flute, piano and tape

by Philippe Lalitte

If the emergence of mixed music in the 1950s brought about a paradigm shift in composition, it soon proved to be a new challenge for performers. They have to tame a technological device (storage, triggering and broadcasting systems), familiarize themselves with the notation of the part on tape and confront themselves with sounds that are not necessarily instrumental (natural environment, biotope, urban and industrial noises, electronics, etc.), more or less familiar and more or less variable depending on the work. The performer must relinquish certain prerogatives, such as control over the overall balance of dynamics and tempo (in the case of music with tape). All these constraints imply limited, often one-way interaction, unlike in chamber music, where problems of timbre fusion, synchronization, balance between parts and auditory feedback are managed moment by moment by the human partners. 
Musicology has paid little attention to questions of musical interpretation after 1945, and even less to that of mixed music. This article is not intended to cover the whole question, but to address some of the issues involved, starting with François-Bernard Mâche's Sopiana for flute, piano and tape (1980). Among François-Bernard Mâche's vast repertoire of mixed works, Sopiana appears to be one of the culmination points of his approach, which consists, to put it very concisely, in confusing the conventional categories of the raw (sounds from the natural elements, the animal world, dead or living languages) and the musical. Sopiana is also one of the composer's most recorded mixed works, with three commercially available discographic versions. These were used to study the performance of this work. In addition, we drew on interviews with two of the work's performers: Pierre-Yves Artaud and Lise Daoust. 
This text is not intended to be prescriptive. The aim is neither to produce a critique aimed at ranking the quality of a particular interpretation, nor to suggest a particular way of performing a particular passage of the score. Our approach is to document mixed-music performance practices, and to identify convergences and divergences between interpretations on specific points (overall sonority, synchronization with the tape, tempo), and then to understand the driving forces behind them.

1. Specific features of Sopiana's mixed sound
Sopiana was composed for flautist Pierre-Yves Artaud, who is its dedicatee and creator. The piece was premiered, with pianist Rita Sin, on July 12 1980 at the Summer Academy in Pécs (Hungary). As the composer states in the notice for the work's first recording (Mâche 2012: 160), the "title Sopiana is derived from the ancient Roman name of Pécs". As the aim of this article is to deal with questions of interpretation, we will not analyse the work exhaustively. Readers will find all the information they need in the analyses by Olivier Loutz (2006) and Márta Grabócz (2013). We will simply recall a few essential aspects for interpretation.
Sopiana is Mâche's twelfth mixed piece since Synergies for ensemble and tape (1963). The content of the tape is in part taken from Naluan for ensemble and tape (1974), a practice already explored with Korwar for modern 16' harpsichord and tape (1972), Rambaramb for orchestra and tape (1972) and Temes Nevinbür for two pianos, two percussion instruments and tape (1973). Sopiana's tape consists solely of the songs of three birds - the Malaysian Shama, the Icterine Hypolaïs and the marsh warbler- chosen for their musical and structural characteristics that bring them closer to human music. The pre-recorded sequences were processed by noise-gate and filtering to eliminate extraneous sounds (environmental noise, distant birdsong, etc.) and retain only what was relevant to the sound model. They were then edited to respect the composer's desired order and tempi. It should be noted that it is possible to play the piece in a purely instrumental version (without tape), especially when both versions are performed at the same concert. However, few (if any) performers have chosen this option to date.
As is often the case in Mâche's mixed music, the instrument/tape relationship is conceived on the principle of over-modeling. The performer must not only synchronize as precisely as possible with the tape, but also adapt his or her playing to the pre-recorded sound patterns. As the bird songs serve as a model for Sopiana's instrumental writing, the score features numerous morphological, gestural and temporal points of contact between the tape content and the instruments, such as intervals (including micro-intervals), melodic features, repeated notes, phrasing, changes of register and timbre across a wide range of playing modes. 
Part notation on tape is of great importance to instrumentalists. This can take a variety of forms, such as notes on a staff, graphics, symbols, textual indications or numbering, depending on the type of event the composer wishes to communicate to the performer. To ensure the best possible synchronization between the instrumentalists and the tape, Mâche chose to transcribe the birdsongs in solfeggio notation, transposing them two octaves lower for ease of reading (they do, of course, sound at actual pitch in the recording). Consequently, in addition to the staves dedicated to the flute and piano, the score includes a staff for the Shama or two staves for the Icterine Hypolaïs and the marsh warbler. 
Notation of the part on tape plays a crucial role when learning the work, as it enables the performer to better understand how the recorded events are articulated, to visualize their temporal relationships with the instruments and, ultimately, to better memorize their content. Pierre-Yves Artaud emphasizes how essential the preparatory work of listening to the tape and reading its solfeggio transcription is to a good performance:
It's a relationship identical to that of the members of a string quartet playing on the ensemble score. In this case, you don't look at it, you "see" it. The graphic is memorized beforehand, and the eye recognizes it like a laser reading a barcode. All the preparatory work is therefore essential: you enter into your memory a "program" in which all the dimensions of the music feature, including visual recognition.
In concert, notation provides a sense of security, enabling the performer to find his or her bearings and improve synchronization with the tape. According to Lise Daoust, it also enables us to anticipate future events:
All tape notation is useful. It allows polyphonic reading. At the concert stage, the cues are well known, but the representation of the tape allows us to anticipate the text, and thus to have a much less anecdotal and microscopic interpretation. In this piece, I learned some sections by heart, quite naturally, for the sake of convenience, especially with the numerous page-turns.
From a formal point of view, the tape is not present throughout the piece (Fig. 1, formal diagram inspired by analyses by Olivier Loutz and Márta Grabócz). Mâche has interspersed instrumental interludes that act as windows of time without the constraint of synchronization with the tape. In this way, the composer offers the performers spaces of freedom that they can exploit to achieve greater flexibility in tempi, playing modes, silences... It should also be noted that these interludes are the sections in which the most advanced playing techniques are to be found. 

Fig. 1: Formal layout of Sopiana.

The formal organization of Sopiana is rondo-sonata. The rondo is divided into sections with the Shama (A) and sections with the Icterine Hypolaïs and the marsh warbler(B), interspersed with five instrumental interludes (I), the last of which is the coda. Five metronomic values are used (in quarter notes): 120 (A1), 116 (A2, A3, A4, A5, B1, B2, B3, I5), 110 (I2), 100 (I3, I4), 45-50 (I1). However, tempo changes are relatively few in number, with the tempo at 116 quarter notes being quantitatively the most represented. The tempi of the interludes are the slowest, with the exception of the coda, which begins at 116 in the quarter note and ends with a prestissimo accelerando (from m. 587). Tempo changes, often associated with preceding pauses (used to trigger the band), play an important structural role in demarcating the major sections.
According to Márta Grabócz (2013), the exposition of sonata form is determined by the first three sections with the Shama and the first two interludes (A1, I1, A2, A3, I2), the development by section B1 alone, the re-exposition by the reprise of the three types of material (A4, I3, B2, I4, A5, B3, I5). From the performer's point of view, however, it is not easy to rely on such an abstract structure. The instrumentalists can highlight the combinations between the protagonists, since we find sections in flute/piano/Shama trio (A1, A3, A5, A6), flute/piano/Hypolaïs ictérine/Rousserolle verderolle quartet (B1, B2, B3), flute/Shama duo (A4), piano/Shama (A2), flute/piano (I1, I2, I3, I4, I5). Sopiana's dramaturgy could therefore be analyzed from a more teleological perspective. It would consist of a first part (mm. 1-269), of fairly light textural density (duets and trios), based on four iterations of the Malaysian Shama, and a second part (mm. 270-597), much more diversified in its sound patterns and textures, culminating in a cathartic coda led by the flute and piano.
2. The recording corpus
The first recording of Sopiana was made in 1982 by Pierre-Yves Artaud and Jacqueline Méfano (piano) at the GRM studios, under the composer's supervision. The vinyl disc also included recordings of Kassandra and Amorgos, performed respectively by the Ensemble du Nouvel Orchestre Philharmonique and soloists from Ensemble 2e2m, conducted by Boris de Vinogradov (Table 1). In his review of the recording, Jean Gallois (Diapason no. 279, January 1983) was particularly moved by the expressive force and virtuosity emanating from the Sopiana recording:
In this page for flute and piano - in which Pierre-Yves Artaud and Jacqueline Méfano shine - Mâche superimposes, prolongs and blends the natural song of two birds with traditional instruments, asking the latter to merge or, on the contrary, to continue the birds' song in the same range of timbres, or to give rhythm to their curves. It's a prodigious, dizzying feat of virtuosity that captivates, subjugates and compels admiration, as virtuosity - which could have been just that - becomes a work of art in its own right. What we hear is a marvellous pyrotechnic of sound, a fabulous piece of prestidigitation, delicately crafted and, through its profound poetry and alliance with Nature, standing in admirable contrast to contemporary production. 
It was not until 14 years later that a new recording by Sopiana was released, this time with Lise Daoust on flute and Louise Bessette on piano, in a disc entitled Mozart et les oiseaux (1996). The program consisted of various Mozart pieces combined with those of contemporary composers. A third recording, with Cécile Daroux on flute and Emmanuelle Bouillot on piano, was released in 2006. The program, entitled La Flûte et les Oiseaux: Hommage à Olivier Messiaen, included works by Messiaen, Debussy, Ravel, Ibert, Saint-Saëns, Ancelin, Kœchlin, Mâche and Prokofiev. Mâche did not supervise either of these recordings. Table 1 summarizes the main characteristics of the three recordings used in this study. In the following text, the interpretations will be referred to by the name of the flutist.
Performers
References
Location
Program
Pierre-Yves Artaud (flute), Jacqueline Méfano (piano) 
Recording supervised by the composer
LP 1982 
CD reissue, INA-GRM, 1999
GRM Studio (Radio-France)
Kassandra, Sopiana, Amorgos
CD reissue: Manuel de Résurrection, Kassandra, Sopiana, Amorgos, Moires
Lise Daoust (flute), Louise Bessette (piano)
CD ATMA Classique, 1996
Studio (Montreal)
Mozart, Messiaen, Levinas, Gougeon, Mâche
Cécile Daroux (flute), Emmanuelle Bouillot (piano)
CD Loreley, 2006

Studio (Paris)
Messiaen, Debussy, Ravel, Ibert, Saint-Saëns, Ancelin, Kœchlin, Mâche, Prokofiev
Table 1: Three studio recordings by Sopiana.

3. Overall characterization of the performances
As a first step, we will attempt to differentiate between the three interpretations of Sopiana. To do this, we have extracted (with MIR Toolbox version 1. 6, Lartillot and Toiviainen 2007) of 14 audio descriptors covering various aspects of the sound, such as timbre (spectral centroid, spectral clarity, spectral spread, spectral roll, spectral flux, spectral irregularity, inharmonicity), sensory dissonance (roughness), noise quantity (spectral flatness, zero-crossing rate), temporal envelope (attack time, attack slope, rhythmic fluctuation) and degree of change (novelty). This signal analysis yielded an average value for each descriptor. We then performed a Discriminant Factor Analysis (DFA) on the 14 quantitative variables (the descriptors) and the three qualitative variables (the three interpretations). The aim was to test whether the descriptors could be used to distinguish interpretations on the basis of sound, and then to represent the data in a two-dimensional space (Fig. 2). 
The percentages of variance obtained for F1 and F2 are 56.85% and 43.14% respectively. The first factor contributes slightly more than the second to explaining the variance. Table 2 shows the contributions of the descriptors to each factor. It can be seen that factor 1 is associated with descriptors of the temporal type (rhythmic fluctuation [0.266], attack time [0.302]), while the second factor corresponds to descriptors of noise (zero-crossing rate [0.676], spectrum flatness [0.523]) and timbre (spectral centroid [0.471], spectral spread [0.423], spectral clarity [0.346], spectral roll [0, 339]). Roughness, novelty and spectral irregularity descriptors make only a minor contribution.
Descriptors 
F1
F2
Spectral centroid
-0,268
0,471
Spectral brightness
-0,493
0,346
Spectral spread
0,014
0,423
Spectral rolloff (95%)
-0,171
0,339
Spectral irregularity
0,115
0,007
Inharmonicity
-0,038
0,113
Roughness
0,013
-0,039
Spectral flux
-0,202
0,079
Spectral flatness
-0,166
0,523
Zero crossing rate
0,059
0,676
Attack time
0,302
-0,206
Attack slope
-0,184
-0,050
Rhythm fluctuation
0,266
0,034
Novelty [Degree of change]
0,036
0,029
Table 2: Contribution of descriptors to each SFM factor.
SFM shows that the descriptors can be used to distinguish the three interpretations. On the two-dimensional representation (Fig. 2), the sections corresponding to Artaud's interpretation are mostly located above the horizontal axis (with the exception of I5), while those of Daoust and Daroux are placed below (with the exception of I1 and A3 for Daoust and B1 for Daroux). If we refer to the descriptors associated with Factor 2, the difference is more a matter of the overall sound of the recordings, including instrumental timbres, room acoustics, miking (type and placement of microphones) and mixing. More precisely, the upper sections will be distinguished by a timbre rich in harmonics (spectral spread) and a high noise level. These two characteristics can be attributed to a number of factors: the sound of the instrumentalists, a mix that favors the noisy sounds of birds, the closer or closer miking of the instruments and the background noise of the recording. Listening to Artaud's version, we hear a close miking of the instruments (particularly the flute on the right), with short, sparse reverberation, and quite a lot of background noise. Conversely, the recordings by Daoust (flute on left) and Daroux (flute in middle) are more reverberant, with microphones capturing more of the room's acoustics and much less background noise (especially for Daroux). From a mixing point of view, the tape is slightly more present in Artaud's recording than in those of the two female flautists. The result of all these characteristics is, in the first case, a pronounced differentiation between the instruments and the tape, leading to a more analytical listening style; in the other, a fusion between birds and humans, favoring a listening style that could be described as more "ecological". The coordinates of the spectral clarity descriptor (F1 -0.493; F2 0.346) suggest that the sections on the left have a rather clear sound color. Listening to Daoust's recording, this characteristic is particularly noticeable. Once again, this is due not only to the quality of the instrumental timbres, but also to the acoustics of the hall and the recording.
AFD factor 1 separates Daroux's interpretation from those of Daoust and Artaud, the latter's sections being placed predominantly to the left of the vertical axis. The coordinates of the descriptors for attack time (F1 0.302; F2 -0.206) and rhythmic fluctuation (F1 0.266; F2 0.034) suggest that the difference may be due to drier or drier articulations and/or rhythmic synchronization. Comparative listening to the interpretations, both for sections without tape (notably I2, I3, I4), and for sections with tape (e.g. B2 or A2), confirms this hypothesis. On the other hand, it seems that the acoustics of the hall had no influence on these parameters, since Artaud's recording is rather dull, whereas Daoust's is more reverberant.

Fig. 2: Discriminant factor analysis.

4. Performers and time in mixed music
Even if Sopiana, for the most part, is subject to the temporal fixity of the tape, it is interesting to check whether there are any discrepancies between the theoretical duration (the score) and the three recordings. The duration of each recording was calculated from the attack of the first note (flute/Shama), to the last note (flute/piano, m. 597). The initial silence and the final resonance of the hall were therefore removed from the calculation in order to obtain precise durations. Table 3 shows the total duration, the cumulative duration of the sections with tape (6 sections A and 3 sections B) and the cumulative duration of the five interludes for each recording.
All recordings have a total duration greater than the theoretical duration (630 s, 10'30). The Artaud version has the greatest deviation from the theoretical duration (60 s), while the Daroux version has the smallest (30 s). The difference of 30 s between these two interpretations corresponds to a deviation of 5%, which is not very much for a 10'30 piece. Table 3 confirms that the discrepancies in duration are mainly due to the non-banded interludes. In fact, we find the same difference of 30 s between the cumulative duration of Artaud's and Daroux's interludes. 

Artaud
Daoust
Daroux
Total duration (in s and mn/s)
692 (11'32)
672 (11'12)
662 (11'02)
Sections A and B
469,97
472,74
468,76
Sections I
222,03
199,26
193,24
Table 3: Total duration of recordings, cumulative duration of sections.
Fig. 3 compares the duration of each section according to interpretation. Unsurprisingly, the differences in duration for the sections with tape are very small, or even non-existent, with the exception of section A4, which begins with a passage for solo flute. Among the interludes, the greatest divergences in duration between performers are to be found in the last three. For sections I3 and I4, these discrepancies can be explained by tempo and the presence of silences whose length can be varied by the performer. In section I4, in addition to the silences, it is possible that the high density of playing modes may have had an impact on tempo. The deviations in section I5 derive from tempo variations, and in particular from the final prestissimo accelerando, as we shall see later. The longest durations of the interludes are systematically found in Artaud's version, while the shortest correspond to Daroux's version. The exception is section I4, where the Daoust version is clearly the shortest (12.58 sec difference with Artaud and 8.35 sec with Daroux). The cause lies mainly in bars 446 and 450: at bar 446, Daoust's way of producing the glissando of flute harmonics takes only 1.96 sec., unlike the other two versions (5.65 sec. and 4.11 sec. respectively). At measure 450, it's the sigh that takes Daoust 1.07 s, unlike the other two versions (1.26 s and 1.61 s respectively).

Fig. 3: Section durations by interpretation.
Sopiana demands great virtuosity, modeled on that of the birds, whether digital (the number of notes to be executed in often rapid tempi) or due to the many advanced techniques of the flute and piano. But, according to the performers we interviewed on this subject, the major difficulty seems to lie in rhythmic precision and synchronization with the tape. According to Pierre-Yves Artaud: 
There's often a slight discrepancy between the birds and the tempi notation, even if the accuracy of the notation is quite remarkable. In chamber music, partners always have to make compromises, because each inner tempo is unique. For Sopiana, this is out of the question: you have to adapt, and this rigidity is the source of the problems.
Lise Daoust agrees:
The major difficulty remains the extreme precision of the rhythm. The tempo is often very fast, very articulate and always synchronized with the tape and piano. Even the slightest deviation is unforgivable!
The question of synchronization between the instrumentalist and the tape was one of the major issues in mixed music until the advent in the 1980s of new technological solutions (MIDI keyboard, Disklavier, MIDI flute, score tracking, gesture controllers, etc.) which, however, did not solve all the problems. Synchronism, as Arshia Cont (2012: 12) points out, is about two things: "the confrontation of two sound universes when writing, and the temporal juxtaposition of two media when performing". Some composers, and François-Bernard Mâche in particular, have seized upon this constraint to create relationships of logic and continuity between sounds of extremely different natures. But bringing heterogeneous elements into harmony requires the performer to pay constant attention to the sound content of the tape. So much so, in fact, that the absence of temporal interaction between the instrumental and the tape can sometimes inhibit the performer in his or her playing. 
To demonstrate the differences in synchronization between the flautists, we used section A3 (mm. 159-204), characterized by a low event density due to numerous, sometimes long, silences. This makes it all the more difficult to synchronize with the tape. We carried out manual detection of 18 attacks on notes common to the flute and Shama using Sonic Visualiser software (Cannam, Landone and Sandler, 2010). To improve attack detection, two filters were previously applied to the audio file. Fig. 4 shows the attack differential between flute and tape for the three performers.

Fig. 4: Section A3, attack differential between flute and tape.
We can see that Pierre-Yves Artaud is almost systematically a few milliseconds ahead (on average 18 ms) of the tape (the Shama), while Daoust and Daroux are almost systematically behind (on average -63 ms and -65 ms respectively). This difference is confirmed by the significant correlation between Daoust and Daroux differentials (.60, p = 0.008). The largest deviations (over 100 ms) are never common to all three interpreters, and rarely to two. In Artaud's case, they are found in notes 12 (-145), 16 (200), 17 (136) and 18 (-160), in Daoust's in notes 2 (-127), 4 (-112), 5 (-168), 6 (-145), 11 (-102) and 17 (-104), and in Daroux's in notes 5 (-157), 11 (-201), 12 (-104) and 15 (-122). The reason for this is difficult to explain. The most likely hypothesis is that these deviations are uncontrolled timing micro-variations. In any case, the deviations do not exceed 200 ms, which shows the degree of precision of the performers in a complex musical situation where synchronization with the tape is made very perilous by the silences that separate note attacks.
We continued our exploration of synchronization with the A4 section (mm. 205-234), which has the peculiarity of beginning with a flute solo (mm. 205-207), followed by the tape (mm. 208-233). We compared the duration intervals between 69 note attacks (main notes only). Note attacks were detected manually using Sonic Visualiser. To facilitate their detection, low-pass filtering was applied to the audio file beforehand. 
Fig. 5 shows the duration intervals. The values vary according to the position of the notes in the score. The two values that stand out the most (intervals 17 and 59) correspond respectively to the bar of silence for the flute (when the tape is triggered) and the flute's flatterzunge glissando for 2.5 bars. Overall, the three interpretations have very similar values. On average, the duration intervals tend to be longer in Daroux's interpretation (626 s) than in Artaud's (541 s) or Daoust's (583 s). 

Fig. 5: Section A4, duration intervals between note attacks.
Table 4 gives the correlation coefficients for the duration intervals, on the one hand for the initial passage without tape, and on the other for the following passage with tape. It can be seen that the correlations are slightly weaker when the tape is absent, but not as much as might have been expected. 

Artaud
Daoust
Daroux
Passage without band
.908, p < 0,0001
.890, p < 0,0001
.941, p < 0,0001
Passage with strip
.958, p < 0,0001
.934, p < 0,0001
.944, p < 0,0001
Table 4: Section A4, correlation coefficients between duration intervals in the initial passage (without tape) and the following passage (with tape).
Listening to the recordings, it becomes clear that the main factors of divergence between the performers are the way in which they play on the breath (particularly the duration of the second note, m. 205), the articulation of the triple eighth-note group in the treble (mm. 205 and 206) and the duration of the silences (particularly before the tape arrives, m. 207).

The coda (section I5, mm. 541-597) is the longest passage in the piece, where both performers play without the tape. It consists of a slow progression based on an ascending glissando flute trill (C3/G5) executed in continuous breathing. After a brief caesura (m. 586), the tempo accelerates (prestissimo accelerando) as the flute holds a G#5. In a context where the tape is absent and the performers are reaching the climax of the work, it is therefore interesting to measure tempo variations to see if they are consistent between the three interpretations and what they reveal about interpretative choices. 
The first observation is that tempo is unstable in all three interpretations, even before the prestissimo accelerando and despite the fact that no tempo change is indicated in the score. As the flute plays a continuous sound, the unstable tempo is probably due to the piano part. The piano part is frighteningly complex, with strokes, arpeggios and aggregates spread over a wide range, articulated by demanding rhythmic writing. It should be noted that this complexity is not pure virtuosity, as it acts as an expressive factor that adds to the tension produced by the flute's glissando. The differences in tempo between the performers are expressed well before the prestissimo. Up to the stopping point (mm. 441-585), the closest tempo profiles are those of Artaud and Daroux (correlation coefficient .46, p = 0.002), while Daoust's diverges sharply from the other performers (non-significant correlations). On the other hand, Artaud's average tempo was the slowest (108.82, SD 16.14), while Daoust's (116.73, SD 13.86) and Daroux's (115.47, SD 16.79) were fairly close to each other. More surprisingly, the trend curves (not plotted in Fig. 6) show an overall acceleration (before the accelerando) for Artaud and Daroux, while Daoust, who started at a faster tempo, slows down. 

Fig. 6: Section I5 (coda), tempo profiles and standard deviation (in black).
The standard deviation (SD) curve shows the passages with the greatest divergence between performers. The first major divergence, between mm. 549 and 552, comes from the change of register and the sigh (m. 551). The silence in Daoust's version is much shorter (518 ms) than in Artaud's and Daroux's versions (966 ms and 817 ms respectively). The second, at mm. 572-574, also corresponds to a change of register and a sigh. This time, however, the silence in Daoust's version is considerably longer (966 ms) than in Artaud's and Daroux's versions (449 ms and 564 ms respectively). The final and most important discrepancy occurs at the end of the section (mm. 593-597), when the pianist attacks a C7 fortissimo four times. The stacked histogram in Fig. 7 shows the duration intervals between these notes and the interval between the first and last. The first two duration intervals are clearly shorter in Daroux's version, which contributes to the deviation of his tempo curve at the end of the coda. This difference in tempo can be interpreted as an expressive choice on the part of this performer, who seeks to raise the tempo to its maximum, the acceleration having begun at the start of the coda. From this point of view, Daroux's interpretation is the one that most magnifies the Dionysian trance character of the end of Sopiana.

Fig. 7: Section I5 (mm. 593-597), time intervals between the four C7 piano notes.

Conclusion
We had set ourselves the goal of documenting mixed-music performance practices and bringing out interpretive styles based on the analysis of a few specific points (overall sonority, synchronization with the tape, tempo). We found that in terms of overall sonority (including instrument timbre, room acoustics, recording and mixing), the three interpretations of Sopiana were clearly distinguishable. These differences in terms of reverberation, sound color, presence and placement of instruments in stereophonic space lead to aesthetics that favor either analytical listening by separating the different parts, or global listening by merging birds and instruments. Analysis of section duration and tempo confirmed a well-known fact: performers take advantage of tapeless sections to regain temporal flexibility. This is particularly true of the longest interludes, such as the coda. Conversely, we found that the way in which notes are articulated, how register changes are handled or how certain playing modes are executed has an influence on tempo and micro-timing. The performer of mixed music therefore has room for freedom, even in the more temporally fixed sections. We also found this to be the case in the personal way of synchronizing with the tape, very slightly ahead or behind. The conclusions drawn from this case study on the interpretation of mixed music cannot, of course, be generalized, as the devices and aesthetics of this musical genre can be so diverse. From a methodological point of view, the precision of temporal data extraction for the study of tempo and synchronization is an aspect that needs to be improved. The use of separate sources (at least for the media part) is certainly one of the avenues to be explored. This research forms the basis of a reflection that should be extended to a vast corpus and enriched by new methodologies.

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