One of the many musical things I do is arrange pieces by other composers. As far as composers go, the easiest for me to arrange is Mozart(probably because of a combination of early and sustained exposure and the melodic and harmonic simplicity on the outside) and the hardest for me to arrange is Beethoven(octaves all over, lots of modulation and harmonic complexity in general, Beethoven bringing the orchestral sonority to solo piano(For example in the Pathetique Sonata first movement)).
As a matter of fact, I am currently arranging Wind Seranade in C minor for piano duet. Before this I looked on IMSLP and the only all piano arrangement I saw of this piece was for 2 pianos 6 hands, which is honestly kind of odd, usually I see multiple solo and duet arrangements of any given Mozart piece. I have even seen piano solo pieces arranged for piano duet and vice versa. I have been told before that in my Mozart arrangements, I stick too closely to Mozart's original and I often get told to add notes that Mozart didn't even use like say adding a ninth to a dominant seventh.
But I have always asked myself:
Am I really sticking too closely to Mozart? I mean, I'm afraid that if I add notes that aren't obviously implied, I will lose too much of the Mozart feel for it to really sound like a Mozart arrangement. And is it really possible to stick too closely to Mozart? I mean, Mozart's complexity is on the inside, not the outside. In other words it isn't the melodic lines themselves but rather the interactions between them that give a Mozart piece its complexity.
whenever I get that sort of feedback telling me to add to what Mozart wrote.
I mean, I know I can stick too closely to Beethoven(I mean, making the piano sound like an orchestra makes having all of Beethoven's notes in an arrangement for an ensemble smaller than an orchestra that doesn't include pianos an impossible task or an all piano ensemble smaller than a piano duet in the case of his orchestral scores), but Mozart? It just seems impossible to stick too closely to Mozart's original. I mean, here is an example of a relatively complex Mozart piece:
That complexity doesn't come from the melody itself like it does in say a Chopin waltz. The complexity doesn't come from the harmony itself like in your typical Beethoven piece which is built from simple melodic and rhythmic motifs and has a bunch of modulations and diminished 7th chords. No, it comes from the interactions between different melodic lines. Mozart's complexity is similar to Bach's complexity in that it comes from these melodic interactions over a simple harmony. Rarely is the melody itself virtuosic in nature in a Mozart piece. But the way the melodic lines interact can make a Mozart piece sound virtuosic.
So, if Mozart's complexity comes from the interactions between melodic lines and not the melodies themselves, and the harmony is pretty simple, is it really possible to stick too closely to Mozart's original in an arrangement?