The primary aim of arpeggiation is to make the instrument sound more full and resonant than it actually is – to make the sound in a way bloom. This superimposes a layer of improvisatory sprezzatura, which has most likely been a standard feature of musical performance until the 20th century, when the concepts of reproduction and authenticity replaced the idea of improvisation.
Point of reference for this phenomenon is the instrument itself. The need to strike notes again or to spread chords is founded in a specific characteristic of the instrument itself. Nothing else is meant by Frescobaldi when he instructed in his preface to the toccatas to "not leave the instrument empty" ("non lasciar vuoto lo strumento"):
"Li cominciamenti delle toccate siano fatte adagio, et arpeggiando; e così nelle ligature, o uero durezze, come anche nel mezzo del opera si batteranno insieme, per non lasciar uoto l'Istromento; il quale battimento ripiglierassi a bene placito di chi suona."
"The beginnings of the toccatas should be played slowly and arpeggiated. In suspensions or dissonances, as well as in the middle of the work, [the notes] should be struck together in order not to leave the instrument empty; and this striking might be repeated as the player likes."
Tagliavini points out1:
"Given the brevity of sound of quilled instruments, one must strike the held notes again in order to maintain the effect and flavour of the dissonance. This technique should be used not only for dissonances, but also elsewhere in the course of a piece (’in the middle of the work’) to keep the sound of the instrument alive and full. Frescobaldi’s aim was, as Diruta puts it, to ’produce the same effect of holding the harmony on the quilled instrument as the air does in the organ’".
In a similiar way the entry in Rousseau's Dictionaire de musique on the arpége is to be understood:2
"What is done on the violin by necessity, it is practiced by taste on the harpsichord. Since we can only get from this instrument dry sounds that do not hold, we have to rewind them on long notes. To make a chord last longer, it is struck by arpeggiation, starting with the low sounds, and observing that the fingers which have struck the first must not leave their touch until all the arpeggio is finished, so that we can hear all the sounds of the chord at once."
Anselm Gerhard, who collected numerous evidence of habitual arpeggiation and stated its "longue dureé", mentions a later German source, Jakob Adlung, stating:3
„Das Spielen auf solchen beseyteten Instrumenten [Clavicymbel, Clavicytherium, Spinet] ist anders, als auf der Orgel. Man muß sich mehr der Brechungen und dergleichen befleißigen, als daß man die Claves zusammen oder allzulangsam anschlägt; denn die Seyten hören bald auf zu klingen.“
["The playing on stringed instruments [clavicymbel, clavicytherium, spinet] is different than on the organ. One has to make more use of arpeggiations and the kind, than striking the keys together or too slowly, for the strings soon stop sounding."]
The necessity of arpeggiation in order to keep the instrument sounding is more significant for historic instruments, that have a less brilliant and sustaining, but more transparent sound than their modern equivalents.4 Breaking and arpeggiating is not only a habit on quilled keyboard instruments. Their permanent use can also be considered to be the characteristic trait of lute playing at the time and it is probably what Francois Couperin meant, when he was mentioning ”les choses luthée” and certainly what later Johann Gottfried Walther meant when specifying the ”Lauten-Art” (manner of the lute) as ”arpeggiando oder gebrochen”.4 Perrine writes:5
"The particular manner of playing all kinds of pieces for the lute consists only in arpeggiation or the separation of voices, as I have notated in the majority of lute pieces put into musical notation below."
As the device is idiomatic for the lute as well as for the harpsichord we can safely assume that frequent arpeggiation and separation were on both instruments applied without further indication, left to the ”discretion” of the player. Regarding its musical character, another English source mentions that this ”art” defines the ”soul” of the lute and makes it sound ”airy and skipping”. It is usually agreed, that the origin of this habit on both, harpsichord and lute, is to be found in the role of the mentioned instruments for accompaniment.
Since it is a device, that so easily allows us to make the instrument sound more rich and full, it obviously became and remained a habit, a ”manner”, on plucked instruments as well as on keyboard instruments. Jumping forward in time, we find e.g. Carl Czerny complaining:
"Manche Spieler gewöhnen sich das Arpeggieren der Accorde so sehr an, dass sie gar nicht im Stande sind, vollgriffige Accorde, oder auch nur Doppelnoten, vollkommen fest und auf einmal anzuschlagen".
["Some players get so much used to arpeggiating the chords that they are not able to strike full chords or even just two notes firmly and at once."]
This is a fascinating document of Carl Reinecke representing a performance style that is still rooted not only in the tradition of improvising or playing improvisation-like, but also preserving an arpeggiated manner that goes back to the century-old habit that fights the missing sustain of keyboard instruments.1 Especially valuable are the rolls for the Welte-Mignon system, as they preserve the exact timing in a most authentic way, but also rolls of the Hupfeld studio in Leipzig are worth being noted. Carl Reinecke, born 1824, praised already in 1835 as a "gracious Mozart player" and being a teacher in the rather conservative Leipziger Konservatorium, presumably preserves a traditional style of playing – perhaps even of the 18th century.
Regarding Reinecke's obviously regular use of arpeggiation, Daniel Leech-Wilkinson already raised the question, if the practise of arpeggiation in connection with the habit of delaying the melody note, might be pointing us to a much older tradition:2
"Most chords are arpeggiated upwards, so consistently that one wonders whether this is harpsichord technique surviving into nineteenth-century playing, or nineteenth-century pianism applied to Mozart. The notes of the melody are almost always delayed, sometimes by as much as 1/5 of a second, which may not sound very much but, when one is used to notes placed vertically in a score being played exactly together, seems a very long time as one listens. […] In Reinecke’s case, the regularity of the arpeggiation and of the accompaniment beat lead us strongly to the sense that the melody is late rather than the bass early, and that too tends to increase the sense of alienation for a modern listener, who is at least familiar with the idea of a low bass note sounding early when an impossible stretch forces it. Reinecke’s playing can’t be explained away like that, and the fact that he is playing Mozart, for us such a regular composer, simply makes the strangeness of his playing more acute. The thought that there might be a historical cause in his youth is almost frightening because of the wholesale rethink it would force about everything we imagine as Classical."