The limit on the number of voices?

Juozas Rimas wrote (January 3, 2004):
What are the pieces (fugues) with most voices in Bach's oeuvre? (I know there is a 6-voice ricercar in the MO (superb music) and a 6-voice canon (BWV1076 - quite nice but just an experiment).

Are 6 voices the maximum for sensible music? (Bach's canons for 7 and 8 voices sound like a jammed record - no music). Did he write a listenable pieces with more than 6 voices?

Did other composers write listenable music employing 6 or more voices?

Bradley Lehman wrote (January 3, 2004):
[To Juozas Rimas] B Minor Mass, Credo is a 7-voiced fugue: 5 voices, 2 violins; plus basso continuo.

Gabriel wrote (January 3, 2004):
< Did other composers write listenable music employing 6 or more voices? >
Whether a piece is "listenable" can only be in the ear of the beholder, but basically, yes!
Tallis: Spem in Alium (40 voices)
Alessandro Striggio: Ecce Beatem lucem (40 voices)
Ockeghem (possibly): Deo gratias (36 voices)
Josquin (possibly): Qui habitat (24 voices)
Robert Carver: O Bone Jesu (19 voices)
Antoine Brumel: Missa Ecce terrae motus (12 voices)

These are just a few multi-part pieces that spring immediately to mind. And there is a vast amount of other renaissance repertoire in 6, 7 and 8 parts and plenty since then too.

To be honest, the question is a bit odd. Why on earth should being written for 6(+) voices make a piece unlistenable?!!

Juozas Rimas wrote (January 3, 2004):
< To be honest, the question is a bit odd. Why on earth should being written for 6(+) voices make a piece unlistenable?!! >
Well, now I'll have to listen to that 40-voice piece by Tallis. How can one possibly discern 40 different simultaneous musical lines is beyond me. Perhaps you meant the piece is to be sung by 40 people? :/

Paul Dirmeikis wrote (January 3, 2004):
< Did other composers write listenable music employing 6 or more voices? >
I don't have precise titles in mind but Ligeti, Penderecki and Stockhausen composed many choral works with far from 6 voices. They are listenable to my ears. Any music is listenable, but any music isn't interesting.

Thomas Braatz wrote (January 3, 2004):
Gabriel listed Tallis and Striggio as having pieces with 40 voices and then wondered if the question was a bit odd. Whereupon Juozas asked: >>How can one possibly discern 40 different simultaneous musical lines is beyond me. Perhaps you meant the piece is to be sung by 40 people?<<

The answer may be found in the following excerpt from the New Grove in the article on Tallis by Paul Doe and David Allinson [Oxford University Press, 2003.] There are indeed 40 separate/different parts divided as indicated below with the help of alternating choirs. This is not quite the same as having 6 or more separate fugal lines running simultaneously as it can happen in a Bach composition where the instruments often are treated independently from the vocal parts.

Thomas Tallis (1505-1585)
>>It was long speculated that Tallis’s monumental 40-voice work, 'Spem in alium,' was inspired by the example of Alessandro Striggio (i). Indeed, the two composers probably met in London in the summer of 1567 during Striggio’s visit to the English court on diplomatic business (see Fenlon and Keyte). Striggio was completing a tour of European courts during which he had presented a 40-voice mass (with a 60-voice Agnus Dei); it seems that in Protestant London he presented not the mass but the 40-voice motet 'Ecce beatam lucem.' The suspicion that Tallis’s work was written in competitive emulation of Striggio’s is confirmed by an account of 1611 in the notebook of one Thomas Wateridge, a law student at the Temple (first published by Fleetwood Sheppard and then forgotten until attention was called to its existence by Roche in 1981). Wateridge reported how a music-loving duke ‘asked whether none of our Englishmen could sett as good a songe’ as that which had been sent into England by the Italians. ‘Tallice beinge very skilfull was felt to try whether he would undertake ye Matter, wch he did and made one of 40 partes wch was songe in the longe gallery at Arundell house.’ It may be presumed that the duke in question was Thomas Howard, 4th Duke of Norfolk, and son-in-law of Henry Fitzalan, 12th Earl of Arundel (d 1580). Arundel House was Henry’s London home; he possessed a vast musical establishment there and at his country residence, Nonsuch Palace. The Arundel connection is given further credence by the appearance of a score of 'Spem in alium' in a 1596 catalogue of music in the library at Nonsuch. Wateridge’s anecdote allows us to establish a relatively secure dating for 'Spem in alium,' between Striggio’s visit in the summer of 1567 and Norfolk’s execution in January 1572; Stevens (1982) made a convincing case for the first performance being given for the Duke of Norfolk in London after his release from prison in August 1570. Milsom (1983) has speculated that Tallis may in fact have conceived the work specifically for the country residence: the banqueting hall at Nonsuch Palace was octagonal and possessed four first-floor balconies, which might have tempted the composer to indulge in a spatial, as well as purely musical, conception. An examination of 'Spem in alium' shows that, where Striggio’s composition was probably designed for semicircular performance, Tallis had designed his music to be heard ‘in the round’, with the listener seated within the circle of performers. As Milsom commented, the exchanges between different choirs ‘acquire a more structural significance, for they take on the quality of a pair of intersecting “cantoris/decani”-like dialogues, the first operating between left and right, the second between front and back’ (1983, i, 190); the music may also be shown to ‘rotate’ around a circle if the choirs are positioned in a particular way. Tallis’s command of pacing and texture is also consummate: reduced sections are driven by expositions of characterful imitative ideas against constantly varying countersubjects, while the forceful tuttis, with their strong harmonic rhythm, frame the work. The sense that this is Tallis’s 'summa' is strengthened by Keyte’s observation (1989) that the work is 69 longs in duration, and that 69 is a cryptogram for TALLIS (using the numbering of the Latin alphabet: 19+1+11+11+9+18). The work survives only in English-texted sources, as 'Sing and glorify heaven’s high majesty;' the earliest source, Lbl Eg.3512, which was not available to the editors of TCM, probably dates from the first decade of the 17th century. The work was sung in 1610 and 1616 at the investiture ceremonies of Henry and Charles, respectively, as Prince of Wales. The making of a contrafactum for these occasions probably ensured the work’s survival.<<

From the article by Iain Fenlon on Alessandro Striggio ((born in Mantua c1536–7 and died there as well on Feb. 29, 1592) in the same dictionary, here are some pertinent excerpts:
>>...since a motet for 40 parts was sung at, and presumably commissioned for, the marriage of Duke Albrecht IV of Bavaria in 1568. Striggio’s occasional works for the Medici continued with the massive 12-voice 'Altr’io che queste spighe,' written for Cosimo I’s coronation as Grand Duke of Tuscany in Rome on 5 March 1570.<<
>>In the music for intermedi, the careful fusion of homophony and counterpoint and an adroit handling of textures and spatially separated choirs show his surprisingly flexible approach to an often perfunctory genre. The pieces for larger forces have open textures, frequent antiphonal effects and changes in timbre, while the more modest pieces make greater use of short imitative motifs and other contrapuntal devices. Rhythms are usually incisive and lively and there is often a foretaste of the declamatory style, an important element in Wert’s later works. Striggio’s music for 'intermedi' seems to have been influenced by Rore’s early five-voice madrigals, particularly in their use of counterpoint and rhythm.<<
>>Striggio seems to have composed little sacred music. The 40-part motet 'Ecce beatam lucem,' for four choirs (of eight,ten, sixteen and six voices) and organ continuo may have been the 40-part motet performed in 1568, although the only surviving manuscript copies are dated 1587. This may also be the work referred to in two other contexts: the 40-voice ‘canzona’ performed for the entry of Cardinal Ippolito d’Este into Florence on 12 July 1561 (though with a different text) and the ‘musica a quaranta voci’ sent to Duke Guglielmo Gonzaga in August of the same year. Certainly Striggio was active in composing for such large forces during the 1560s; a mass for 40 voices was performed in both Paris and Vienna during his travels around Europe in 1567. For the 1568 Bavarian wedding the voices were accompanied by eight trombones, eight violas, eight flutes, harpsichord and bass lute. In its alternation of soloists and chorus and in its spatially separated choirs, 'Ecce beatam lucem' resembles his large dialogue finales written in the 1560s for the Florentine 'intermedi,' particularly the fifth 'intermedio' for 'La vedova' (1569).<<

Thomas Braatz wrote (January 3, 2004):
[To Juozas Rimas] Juozas, do a search on "Choreinbau" on Aryeh's site. BWV 45/1 is a typical example where Bach combines an instrumental ritornello/introductory sinfonia consisting of at least 3 - 4 parts with 4 additional vocal parts which are added later on in the composing process, at such points (these are usually only sections of the entire mvt.) Bach will easily have 7 or 8 parts performing simultaneously different melodic lines. Very often, however, in Bach's larger choral mvts. from the cantatas, he will have the instruments play independent snippets that are derived from the musical material presented in the ritornelli, but then just as quickly revert to a colla parte instrumental accompaniment to support the voices. It is difficult to find larger choral/instrumental mvts. where Bach sustains throughout the entire mvt. the independence of the instrumental 'voices'/parts over and against the vocal parts sung by the choir. Often the instruments play fragments, but rarely sustain a part for any considerable length of time as in a fugue.

Choral compositions for double chorus (8 voice parts divided into 2 choirs) were difficult for Bach to perform as part of the regular Sunday services. As Alfred Dürr pointed out in his discussion of BWV 50:

1) Bach did not have sufficient singers [two separate sets of 'concertisten' = choir sectional leaders] to perform compositions for double choir except on very special occasions.'

2) More typically, because of these restrictions, Bach preferred to write 5-part choral music if he wanted more than just the usual 4 parts.

3) According to William H. Scheide, BWV 50, for instance, was originally a 5-part composition by Bach which someone else expanded to the now existing version.

4) It is atypical for Bach to use "chord-like thickening" of the main themes, as can be observed in this composition (BWV 50).

[My comment: it would appear that Bach was primarily limited by physical circumstances which dictated the number of voices/parts that he would write. Of course, the exceptions come to mind such as in the 2nd version of the SMP. This would seem to indicate that Bach was striving for a double-choir ideal which was extremely difficult to realize. In the opening chorus of the SMP, it is, however, much more of a stereophonic effect (compare with Tallis) which Bach achieves with one choir interjecting short questions while the other has sustained 4-pt. writing, or both choirs throwing short chords or phrases back and forth rather than actually providing all the independent voices of a fugue. When the separate choirs are joined in sustained singing, which is not too often, the parts most often are duplicated and are not independent. Only rarely does Bach have up to 8 separate, primarily independent parts going simultaneously (including the c. f. sung by the boy sopranos.)]

I may easily have overlooked something and would welcome other responses to help answer Juozas' query.

If I understand Juozas' question properly, I think that he may be referring to truly separate independent parts that continue throughout the duration of the piece, rarely pausing, but rather supplying significant melodic material as one would expect in polyphonic or fugal composition. Another interpretation of the question would be: is there a musical limitation that even Bach must adhere to when composing polyphonically? Is there a point when the mind is no longer able to distinguish/keep apart all the significant parts/voices?

Juozas Rimas wrote (January 4, 2004):
Thomas Braatz wrote: >>> If I understand Juozas' question properly, I think that he may be referring to truly separate independent parts that continue throughout the duration of the piece, rarely pausing, but rather supplying significant melodic material as one would expect in polyphonic or fugal composition. Another interpretation of the question would be: is there a musical limitation that even Bach must adhere to when composing polyphonically? Is there a point when the mind is no longer able to distinguish/keep apart all the significant parts/voices?<<<
It's precisely what I meant. When I'm listening to the 6-voice ricercar in the MO or even to some contrapuncti of the AoF with "only" 4 voices, it feels to me it's almost the limit: add one or two more voices and everything will turn into chaos. Perhaps those Bach's late works provide the thickest fabric of counterpoint possible. Indeed, the thickness must be not about the sheer number of voices but rather about how really independent they are and for how long they go simultaneously. So Bach's mere four voices in an AoF contrapunctus may well sound "thicker" than Tallis' forty.

Bradley Lehman wrote (January 4, 2004):
[To Juozas Rimas] Juozas, other than those tight little canons you mentioned below:

That 7-voiced Credo fugue in the BMM (BWV 232) is the biggest complete, strict Bach fugue I can think of at the moment (7 strictly fugal parts, equally melodic and sharing musical material all the way through...plus a free bass). As I mentioned below, two of those fugal voices are played by the violins instead of sung; they're simply too high to sing.

But I remember from singing in performances of the motet BWV 229: he has a chromatic eight-voiced fugato (= short fugal section until the texture dissolves into something else) on the text "der saure Weg wird mir zu schwer!" That's a nice little illustration by Bach there, word-painting about the difficulty of listening to eight fugal parts at once. :)

Of course, none of this is to be confused with orchestration of anything, where there could be much more happening at once than eight parts. I assumed you're asking about strict fugal sections. Right?

p.s. Another good 6-voiced Bach fugue not to miss is the "Pleni sunt coeli" of BMM. The most extraordinary spot in that one, in my opinion, is in measures 96-99 (where the first measure of it was numbered "48"). The four lowest voices have a close stretto of the word "gloria", entering one measure apart, a 5th apart each time: on G, then a [diminished] 5th below on C#, then a 5th below on F#, then a 5th below on B. (Normally, in a stretto of a fugue, one expects the voices to enter with a mixture of 5ths and 4ths apart, not all 5ths. Tonic, dominant, tonic, dominant, etc: "real" answers and "tonal" answers.)

Charles Ives wrote a fugue like that much later, on the hymn tune "The Shining Shore," having his four voices enter a 5th apart so there are four keys going on at once, fighting it out. That one upset his teacher who had been expecting something more traditional sticking to only one or two keys. But then again, Mozart's "A Musical Joke" K522 ends in five different keys at once: the horns playing in F major, the bass in Bb major, the viola in Eb major, the second violin in A major, and the first violin in G major. Spicy way to end a piece.

Also don't miss the fugues in Bartok's "Mfor Strings, Percussion, and Celesta."

Ganriel wrote (January 4, 2004):
Thomas Braatz wrote: < There are indeed 40 separate/different parts divided as indicated below with the help of alternating choirs. This is not quite the same as having 6 or more separate fugal lines running simultaneously as it can happen in a Bach composition where the instruments often are treated independently from the vocal parts. >
Undoubtedly true, but your point is.....?

Spem in Alium is for 8 5-part choirs but all 40 voices are often in play simultaneously.

Gabriel wrote (January 4, 2004):
Somebody writes: < Perhaps you meant the piece is to be sung by 40 people? >
No, I meant what I said. It is in 40 real parts.

Thomas Braatz wrote (January 4, 2004):
I had stated previously:
“There are indeed 40 separate/different parts divided as indicated below with the help of alternating choirs. This is not quite the same as having 6 or more separate fugal lines running simultaneously as it can happen in a Bach composition where the instruments often are treated independently from the vocal parts.”
And Gabriel asked and stated:
>>Undoubtedly true, but your point is.....? Spem in Alium is for 8 5-part choirs but all 40 voices are often in play simultaneously.<<
This afternoon I listened to “The Sixteen Choir” with Harry Christophers conducting this piece with 8 choirs, each consisting of 5 voices on Chandos 0513, but unfortunately this recording from October 15-17, 1989, was not made with quadraphonic or surround sound in mind. There seems to be some ‘sound spacing’, but certainly not enough to do this piece justice. This composition depends upon the spatial quality which is, for the most part, lacking in this recording, as marvelous as this piece of music is. It does sound like many separate voices are constantly merging into a uniform sound of about 5 or 6 parts with occasional high soprano parts suspended above them. Without being in the center of the space and having the choirs singing toward me from different directions, this piece loses substantially the effect that it is supposed to have. Hopefully some future recording process will be able to accomplish this feat which is already available in recent DVD film productions played over a surround-sound system.

The music itself has a few dramatic moments, but there are long sections revolving around a limited number of progressions and tonalities. In a composition by Bach [this would be, of course, a later time and place than that in and for which Tallis was writing and therefore not really a fair comparison] there would be more of interest occurring musically all the time and much less repetition of the same material. Again, in Tallis, this may not be actual repetition, if one hears similar segments moving about from choir to choir. Such a result could then, nevertheless, be quite exciting for a listener.

Gabriel wrote (January 4, 2004):
Thomas Braatz wrote: < Without being in the center of the space and having the choirs singing toward me from different directions, this piece loses substantially the effect that it is supposed to have. >
How do you know what effect the the piece is supposed to have? Are you Thomas Tallis?

David Glenn Lebut Jr. wrote (January 4, 2004):
[To Juozas Rimas] The Matthaeus-Passion (BWV 244) has (I think) the right to claim the title of the most voices in a Bach work (especially in the 3 version of 1742, with the Ripieno Sopranchor). Also such works as BWV 680 and 686.

Thomas Braatz wrote (Januarty 4, 2004):
Gabriel asks: >>How do you know what effect the the piece is supposed to have? Are you Thomas Tallis?<<
You may have missed my message which included the following excerpt from the New Grove in the article on Tallis by Paul Doe and David Allinson [Oxford University Press, 2003.]:
>>Milsom [J.R. Milsom: English Polyphonic Style in Transition: 'A Study of the Sacred Music of Thomas Tallis' (diss., U. of Oxford, 1983)] has speculated that Tallis may in fact have conceived the work specifically for the country residence: the banqueting hall at Nonsuch Palace was octagonal and possessed four first-floor balconies, which might have tempted the composer to indulge in a spatial, as well as purely musical, conception. An examination of 'Spem in alium' shows that, where Striggio’s composition was probably designed for semicircular performance, Tallis had designed his music to be heard ‘in the round’, with the listener seated within the circle of performers. As Milsom commented, the exchanges between different choirs ‘acquire a more structural significance, for they take on the quality of a pair of intersecting “cantoris/decani”-like dialogues, the first operating between left and right, the second between front and back’ (1983, i, 190); the music may also be shown to ‘rotate’ around a circle if the choirs are positioned in a particular way. Tallis’s command of pacing and texture is also consummate: reduced sections are driven by expositions of characterful imitative ideas against constantly varying countersubjects, while the forceful tuttis, with their strong harmonic rhythm, frame the work.<<

and Iain Fenlon on Striggio also in the New Grove:
>>Certainly Striggio was active in composing for such large forces during the 1560s; a mass for 40 voices was performed in both Paris and Vienna during his travels around Europe in 1567. For the 1568 Bavarian wedding the voices were accompanied by eight trombones, eight violas, eight flutes, harpsichord and bass lute. In its alternation of soloists and chorus and in its spatially separated choirs, 'Ecce beatam lucem' resembles his large dialogue finales written in the 1560s for the Florentine 'intermedi,' particularly the fifth 'intermedio' for 'La vedova' (1569).<<

Gabriel wrote (January 4, 2004):
Thomas Braatz wrote: < You may have missed my message which included the following excerpt from the New Grove in the article on Tallis by Paul Doe and David Allinson [Oxford University Press, 2003.]: >
I didn't miss anything. The fact remains that neither you, nor Paul Doe or David Allinson for that matter, actually know what Tallis's intentions for this piece were.

"An examination of 'Spem in alium' shows that, where Striggio’s composition was probably designed for semicircular performance, Tallis had designed his music to be heard ‘in the round’, with the listener seated within the circle of performers. As Milsom commented, the exchanges between different choirs ‘acquire a more structural significance, for they take on the quality of a pair of intersecting “cantoris/decani”-like dialogues, the first operating between left and right, the second between front and back’ (1983, i, 190); the music may also be shown to ‘rotate’ around a circle if the choirs are positioned in a particular way."

Whilst they are quite right to assert that Spem works very well if performed with the singers in a circle, with the audience in the middle, it is stretching things a bit to state categorically that is how it was intended to be performed. Many performers of Spem place the singers in a semicircle in front of the audience which is a perfiectly reasonable way to present the piece.

Gabriel wrote (January 4, 2004):
Thomas Braatz wrote: < You may have missed my message which included the following excerpt from the New Grove in the article on Tallis by Paul Doe and David Allinson [Oxford University Press, 2003.]: >
Furthermore, the quotations from Doe, Allinson and Milsom only address the possible intended spatial layout of the performers. The intended effect of the piece - only the composer can know that.

Juozas Rimas wrote (January 4, 2004):
Juozas Rimas writes: << Perhaps you meant the piece is to be sung by 40 people? >>
Gabriel wrote: < No, I meant what I said. It is in 40 real parts. >
Are Mozart's quintets in 5 real parts just because 5 instruments sometimes play simultaneously in them?

Gabriel wrote (January 4, 2004):
[To Juozas Rimas] Yes, of course they are!

Tomek wrote (January 4, 2004):
[To Juozas Rimas] I would rather say: No.

Mozart in chamber music used instrument's in a different way than Bach human voicesin motets or Cantatas. In my opinion we was deliberating from the beginning about "parts" and "voices" in polyphony. Mozart used polyphony very rarely (although there some pretty nice exceptions). In Mozart quintets additional instrument enrich the harmony, colour, volume, but not structure of polyphony - certainly except some fugatti here and there.

I think the best example for struggle between the mozart-way and the bach-way (between homophony and polyphony) is Beethoven Grosse Fuge op. 133 or Fuge from piano sonata in A flat major op. 110 - just listen to it!

Pablo Fagoaga wrote (January 4, 2004):
[To Gabriel] I'm not an expert, but I guess, to this point, we are mixing two differet concepts here.

Fugal constructions ,are not just many parts written in separate staffs, but a complex of strictly related lines, ruled not just by the obvious fact that they are independently written but mostly because of a series of ruled RELATIONS between those parts (exposition of subjects, countersubjects, and much more which clearly can be explained with authority by informed members).

Anyone can write five millon part pieces, for instance making exact duplications, mere transpositions of a single melody or adding just freely related lines.

Fugal composition is a quite different task, hence the limits shown even by Bach in the mumber of voices. I suspect that Bach limits were not intellectual, but because of his obvious good taste.

The lines have to respect strict relations, so it is not impossible to think of certain limit in which formal rules would turn the piece into a mere scientifical exercise, since the many lines would tie together as they appear.

When the question about number of parts arised, I think if was meant to inquire not about "multi-part" pieces in general, but fugues in particular.

Juozas Rimas wrote (January 5, 2004):
Pablo Fagoaga wrote: The lines have to respect strict relations, so it is not impossible to think of certain limit in which formal rules would turn the piece into a mere scientifical exercise, since the many lines would tie together as they appear. >
By the way, Bach's own BWV1072 (Canon trias harmonica a 8 in contrary motion) and BWV1078 (Canon super fa mi a 7 post tempus musicum) ARE mere scientifical exercises of the old man...

I wonder what he really meant by writing those. I've heard he had to write some of those puzzles to enter a certain club and his entry pieces was the canon he is holding in his hand in his famous portrait.

Stephen Benson wrote (January 5, 2004):
Thomas Braatz wrote: < Without being in the center of the space and having the choirs singing toward me from different directions, this piece loses substantially the effect that it is supposed to have. Hopefully some future recording process will be able to accomplish this feat which is already available in recent DVD film productions played over a surround-sound system. >
A few years ago, while wandering through Montreal's modern art museum, I heard in the distance the sounds of choral singing. Drawn irresistibly to this unexpected treat, I recognized, as I got closer, the ethereal strains of "Spem in alium". Eventually, I arrived at a room inhabited by a half dozen visitors wandering among 40 audio speakers arranged in a large circle, eight groups of five speakers, each speaker on its own pedestal bringing it to head height. Canadian artist Janet Cardiff had created the installation entitled "Forty-Part Motet", each speaker producing the voice of a single chorister of the Salisbury choir recorded in a single live performance of "Spem in alium". Alternating between lying on the floor in the center of the circle in order to grasp the whole and standing in front of each five-voice choir as well as each individual singer, I spent a joyous afternoon enthralled by the unique opportunity to revel in the richness and intricacy of Tallis's polyphony.

Peter Bright wrote (January 5, 2004):
[To Juozas Rimas] You can hear these and other late canons on a number of recordings, my favourite being the Hannsler release of the Musical Offering (the canons 1072-1078 and 1087 are included at the end). BWV1087 refers to the very interesting 14 canons Bach wrote on the fundamental bass notes of the aria to the Goldberg Variations, discovered in 1974. The triplex canon (no. 13) is a reworking of BWV 1076 which is seen in Bach's hand in that Haussmann portrait. By that 'certain club', I believe you are refering to the Mizler Society?

David Glenn Lebut Jr. (January 6, 2004):
[To Pablo Fagoaga] I agree...this thread does seem to lose the differentiation between "part" and "voice". Here is what I understand the difference is:

1.) Part: a voice/instrument dictated by a clef-i.e., Sopran, Alt, Tenor, Bass (that is, Soprano, Alto, Tenor, Bass). A good example iof this is the old Middle German tradition of "Part-Singing" and such works as the famous "Kanonon a Ground a3 D-Dur" by Johann Pachelbel (here we have a composition for 3 principle parts with a
fourth being the Continuo "Ground").

2.) Voice: A. A singing range. B. one note or series of notes of music that is played at a given time. A good example of this is the series of Inventionen and Sinfonien. Here these works are written for either two or three voices. Another good example is the Vier Duetten aus der Klavieruebung III. These are more in reality two-voice Inventionen than Duetten.