From time to time discs are released with a mixture of early and contemporary music. The latter term shouldn't be taken too litterally: here I refer to music composed later than, say, the mid-20th century. Even though I can't get tuned in to modern music, such programming can be interesting, in particular as some modern composers are influenced by composition techniques used in the past, especially the renaissance. It can only be assessed positively that they don't feel obliged anymore to follow slavishly the 'rules' of contemporary music.
In such cases composers specifically link up with old traditions. But there are also modern composers whose works show some similarities with early music, even though they are not explicitly influenced by it. Some composers of the 20th century give much freedom to interpreters, allowing them to achieve very different results in the realisation of their scores. This freedom, turning the performer into a kind of 'co-composer', is sometimes considered as not very different from the liberties interpreters of early music should take. A recent recording by the German ensemble Lautten Compagney, directed by Wolfgang Katschner, underlines the similarity between the role of 'improvisation' in the music of Philip Glass (1937), the main representative of 'minimal music', and the Italian composer Tarquinio Merula (1595-1665) (*).
In her programme notes Babette Hesse underlines the fact that in Glass' music, in particular after him becoming acquainted with the music of Ravi Shankar, the absence of bar lines gives an almost endless freedom to the interpreter. And then she states that modern interpreters can look at Merula's music the same way. "There is a basic beat, but no bar lines, and no cross bars grouping the notes clearly together. Nor is there a score as such showing the entire composition at one glance: instead, the editions only provide the separate parts, which don't come together until the piece is actually played." Merula is not unique in this respect. "17th centry composers didn't see any necessity to record every detail of the performance in writing: they assumed that the players themselves would make their own creative contribution."
For decades interpreters of early music concentrated on finding the right instruments and understanding the way they should be played and the music should be interpreted. The amount of freedom they took was limited. As today the playing of early instruments has greatly evolved and the understanding of early music has increased, it is possible to grasp and explore the freedom composers of the past gave the interpreters.
In order to use the room for improvisation correctly, one first needs to understand the character of a particular composition and the style and performing habits of the time in which it was composed. In that respect the evolution from a strict performance of what was written down to a more improvisational style is logical. It is therefore regrettable that modern performers who should know better, don't hesitate to use the freedom to perform compositions in such a way that the composer wouldn't recognize them.
I don't know if the freedom Philip Glass expects his interpreters to take is limitless, and whether he wants them to at least respect his style. Would he be satisfied with a performance of his compositions in the manner of the 17th century? At least that is historically possible as the instruments of the 17th century are still used and the style of performance of that time is known. But performing Merula as if it was 20th-century music is something quite different. Instruments like saxophone and marimba, as they are used by the Lautten Compagney to perform some pieces by Merula, are very different from anything he knew. And improvisation in 20th-century style is different from what was practiced in Merula's time.
Of course the members of the Lautten Compagney know this very well, as they are seasoned interpreters of early music. Then why do they do things like this? If they really believe in the quality of Merula's music, then why do they think it is necessary to jazz it up? I am ready to accept that they really believe this is a way to show that Merula's music isn't just old stuff, but still very much alive. But in my view they have murdered Tarquinio Merula instead.
(*) "Timeless: Tarquinio Merula - Philip Glass" - Lautten Compagney/Wolfgang Katschner (deutsche harmonia mundi 88697526982)