Conclusion

Tango and Salsa are both well known as partner dances from Spanish-speaking countries. When we look at pieces of both genres, we see a huge difference between the musical aspect of the dances. However in these two pieces, they are both written in canon chordal structures, they both have thick textures, extensive string parts, solos, contrasting tempos, several themes, time signatures, and they both having a very moving forward theme in them. From looking at the musical aspects of Piazzolla's Invierno Porteno and Gershwin's Overtura Cubana, we can find the similarities between the genres of Tango and Salsa.

Chord Structures

To further compare the two pieces, we should look at some of the chord structures of them. Both the Tango and the Salsa are canons, which means one voice repeats another at different times throughout a piece using the same chords over and over again. 

At the end of Piazzolla's Tango, the chord structure is the following:

I V vi ii V I  IV V

(using roman numerals, and the lower-case letters represent minor keys)

Tone Colour

 Tone colour, also known as timbre, is a term that describes the quality of sound in music. Timbre is what makes a particular musical sound different from another, even when they have the same pitch and loudness. For instance, it is the difference between a guitar and a piano playing the same note at the same loudness. Both pieces have string instruments, (cellos, violins and a bass) but Gershwin's Overture has a full orchestra with wind and brass instruments, which gives it a different tone colour. There are more instruments in Gershwin's piece, while Piazzolla's is just a trio. Therefore, Gershwin's piece has a thicker and richer tone than Piazzolla's. 

Structures

Before we analyze the structures of the two pieces,  we should first analyze what the structure of a piece of music even is. A songs structure is how it's organized. An example of the structure of a song is intro - verse -hook - chorus - verse - hook- chorus -bridge - chorus -coda. (this is the structure of most popular music today). To further analyze what a song structures are, these are the definitions of the parts of the structures:

Chorus: The chorus is a lyric-music combination that is repeated with little or no change throughout the song. Usually, the chorus lyrics include the song title and gives the listener a general idea about the song topic. The chorus music includes the most catchy melody in the song...The chorus is generally the part that your listener will remember from your song.

Verse: The verse has the second melody of the song, this melody hardly changes throughout the song. What changes is actually the verse lyrics; as the verses usually give details about the song topic.

Bridge: The third melody and the one that is -in most song structures- appearing only once. It is better if the listener gets a "tiny" surprise in the bridge; that can be a change in the chord structure accompanied by a smooth shift to another scale...etc. However, the bridge melody always ends by shifting back to the original mood and repeating the chorus all over again. As for the bridge's lyrics they usually represent a conclusion or a flash back to the whole song, this adds to the surprise. 

Coda: The outro of a song- the ending.

The structure of Gershwin's Overture is ternary form. Ternary form is a three-part music form-usually schematized as A-B-A. What this means is the first and third part (the A's) are musically identical, and if not very similar. The B section provides a contrast from the two A sections. The B section is generally in a contrasting, but closely related key, usually the dominant key of the first section's tonic (a perfect fifth above) or the relative or parallel minor or major, less often the sub-dominant key (a perfect fifth below).

The first part (moderato e molto ritmato) is preceded by a (forte) introduction featuring some of the thematic material. Then comes a three-part contrapuntal episode leading to a second theme. This first part finishes with a recurrence of the first theme combined with fragments of the second.

A solo clarinet cadenza leads to a middle part, which is in a plaintive mood. It is a gradually developing canon in a polytonal (which means  several tones together) manner. This part concludes with a climax based on an ostinato of the theme in the canon, after which a sudden change in tempo brings us back to the rumba dance rhythms.

The finale is a development of the preceding material in a stretto-like manner. This leads us back once again to the main theme.

The conclusion of the work is a coda featuring the Cuban instruments of percussion.

The form for Piazzolla's Invierno Porteno is not in a certain form. This is the structure of the Tango from beginning to end:

Slow intro Theme A (minor key)
Fast - theme A’
Transition
Slow tempo- Theme B
Fast Tempo- New Material (pentatonic –open 5ths) Theme C
Slow tempo (cello) Theme D
Theme D passed to violin
Fast Tempo Theme D’
E theme passed to piano
Slow Theme D
Slow theme new material “E” –passed from strings to piano.

The form of Piazzolla' piece is built among the tempos of the piece. All Tangos follow the pattern of a slow intro, then the tempo speeds up and the pattern continues until the slow outro. The slow tempo sections are in 3/4 time, while the faster tempos are in 4/4 time. (the 4/4 time signature gives it more of a moving forward pace). 

The Tango

TANGO….Just the word conjures up exciting images and inspires many 

associations and interpretations, such as passion, sensuality, drama, gender wars, even 

violent ones, a national identity, a by-gone era, and a universal art form.

 According to the Grove Dictionary and Oxford Music Online (subject heading "Tango"), a tango is a piece "in duple meter  with a characteristic rhythmic figure, it consists of two sections, the second usually in the dominant or relative minor." It gives the rhythmic figure as one of the following two possibilities:

1. Dotted eighth plus sixteenth, two eighth-notes
2. Sixteenth plus eighth plus sixteenth-note, two eighth-notes

The Harvard Dictionary of Music defines the tango as being a song in two equal repeating sections; the first section being in one key and the second being in either the key of the dominant or relative minor of the original key. This structure is very important to early and modern tango styles.

The musical element that really sets tango apart from other song types is syncopation. Most often seen written in 2/4, it is characterized by being in a duple meter (2/4 or 4/4 commonly). As Tango progresses throughout the musical time periods, the syncopation becomes more and more complex. However, simple repeating syncopated rhythms (8th-dotted, 16th, 8th, 8th) are very commonly heard.

Tango music is usually just associated with dancing, but there is also a common lyrical thread. The Harvard Dictionary of Music also says that originally the songs were often about urban or social issues, originating in urban areas of Argentina.

 It is traditionally played by a sextet, known as the orquesta típica, which includes two violins, piano, double bass, and two bandoneóns. Earlier forms of this ensemble sometimes included flute, clarinet and guitar. Tango may be purely instrumental or may include a vocalist.

All sources of Tango stress the influence of African communities and their rhythms, while the instruments and techniques brought in by European immigrants in the 20th century played a major role in its final definition.

The Tango usually features violins playing in the melody along with the Piano and Bandonean. The Tango can usually be improvised. There's always four beats to a bar and feature syncopated (off beat) rhythms (because it is a dance). Tangos are also always in a minor key and feature layers of ostinato. (repeated patterns)

There is no percussion section in the tango orchestra, but rhythmic patterns are

heard in different instrumental layers of the texture. The bass line often carries the

prominent dance rhythm, or perhaps it may be in an accompanying middle part such as

the bandoneón or the string section.

History of the Tango

The history of the Tango is as colorful as the dance itself. 

The Tango evolved from Folk dance and Milonga- having at it's heart a multitude of cultural influences. 
There is still much controversy of all the roots of the Tango, however one undeniable truth remains the immense influence of Afro-Argentines in the formation of the Tango. The name itself, "Tango", is widely believed to be of West African origin meaning "closed space" or "reserved ground". Only later did the word tango come to refer specifically to Afro-Argentine dance, before being ascribed to the specific form of couple dancing we know today as the Tango. Both the dance and the musical style known as Tango has three main antecedents, the lunfardo, the milonga and the candombe, each of which represents a different component of the Argentine cultural mosaic.

The composer that wrote Invierno Porteno, Astor Piazzolla, is known for revolutionizing traditional Tango to Tango Nuevo, which combines characteristics of traditional Tango with Classical music and Jazz. Piazzolla played the Bandoneón in the orquesta tipica of Anibal Troilo until 1944. Between 1944 and 1949 he formed his own orquesta tipica that deviated from the Tango of that time in both harmonic complexity and rhythm. He began composing and directing Tango Nuevo in 1955 when he lived in Buenes Aires.

Tango Nuevo has evolved further during the 1970's, 80's and 90's with the influence of Jazz, which moved Tango even further into an experimental genre - which around the year of 2000 brought on the age of Neo- Tango, a logical progression.

Salsa Music

Although Gershwin's Obertura Cubana isn't a typical Salsa piece, it has sections of it in which Salsa elements lie.

What makes Salsa music different than other types of music is the key difference that Salsa uses a lot of percussion and a greater focus on rhythms. The percussion involves many people to play, and many instruments to play on. Salsa music almost always has a 4/4 time signature, with the exception of of some African based songs. The tempo often stays the same in Salsa music, as it does not speed up or slow down. 

The Clave Rhythm

All Latin music is based around the ancient Clave rhythm. Most of the time, the Clave is in 6 beats instead of 8 beats,which is why sometimes the rhythm changes to a 6/8 measure to quote this African rhythm. But mainly, the music stays in 4/4 time and is based on the 8 beat version of the Clave in Salsa music. The Clave is also a a 2-measure rhythm. 

The Rhythm Cheat Sheet shows the beats of the clave. Note that one of the clave notes is on an up-beat – between beats 6 and 7 of the count. The following audio clip explains the rhythm and how it fits the beats of the count:

SAMPLE: 2-3 clave with counting

Music is “phrased” differently on different songs. In some cases, the emphasis of the music is on the 2-side of the clave. This means that musical phrases or lyrics start on the measure that is the 2-side of the clave. Hence, such music is referred to as being in “2-3 Clave”. In other cases the phrasing is such that the emphasis is on the 3-side. That music is referred to as being in “3-2 Clave”, which is explained in the following clip:

SAMPLE: 3-2 clave with counting

To make matters even more confusing, the phrasing of the music often changes DURING the same song. So, the clave sense will change from 2-3 to 3-2 and visa-versa during a song. NOTE that the clave itself never changes from start to end of any song. It is just the phrasing of the music that changes! Any section of music that has an odd number of measures will cause the clave (2-3 to 3-2 or opposite) to switch.

Salsa Band

A Salsa band often has 3 percussionists. The 3 players often play different rhythms that often fit together to form the overall complex rhythm. The three players play, 1-Conga, 2-Timbale, and 3-Bongo/cowbell. 

In addition, there is usually a piano and a bass player that form the rest of the rhythm section. There are also sometimes horn players and singers. 

Rhythm players also play a "basic" too- in other words, they play a basic rhythm as their part when the music is steady.  In songs there are "breaks"  which are extra rhythmic passages and of course each player will embellish their playing with other variations while they're playing. 

The basic rhythm is called the "Tombao" or sometimes "Marche".

The Conga Rhythm

The Conga drum is the basis and core of the rhythmic section and it plays a rhythm that emphasizes the 2nd and 4th beat.

SAMPLE: Conga beat explanation

Here is a clip of the conga beat with the clave on top of it:

SAMPLE Conga beat medium with Clave

The “slap” that the conga player hits on beat 2 is loud and identifiable and dancers that dance on-2 will use that to sync up. But it can be very confusing to people trying to find “1” in the overall count!

THE BASS RHYTHM

The bass tumbao is actually a subset of the clave itself. Note that ALL of the rhythms discussed here contain emphasis on clave beats which gives the overall music the feel of the clave. So, experienced listeners can pick out the clave quickly in the music. The bass plays the upbeat between musician’s count 2 and 3 plus the beat 4 in every measure. This is like repeating the last two notes of the 3 side of the clave continuously. It is explained in the following clip:

SAMPLE : Bass beat with counting

THE PIANO RHYTHM

The piano plays a basic rhythm called “montuno” which is also the type of music from which Salsa derives.  It is explained in the sample below:

SAMPLE: PIANO medium with counting

THE BELL AND GUIRO

The bongo player in the band plays drum during the verses or “down” sections of the music. The basic marche rhythm for bongo is only 1 measure long and it is basically 1-and-2-and-3-and-4-and, or every ½ beat. The sound played on 4 of the beat is on the lower of the two drums in the bongo and hence a lower sound.

When the music energy picks up, the bongo player in turn picks up his bell or campana and plays to keep a basic time for the band. The open sound – when he hits near the mouth of the bell – comes on beats 1 and 3 of every measure and is often referred to as the pulse. 

The Guiro is traditionally made from a gourd with ridges cut in it to make a scratching sound with a stick is pulled along the ridges. The sounds of the Bongo Bell and the Guiro are explained in the next clip:

SAMPLE: BELL AND GUIRO medium with counting.

THE TIMBALE

The third main percussion player in a salsa band plays the closest thing resembling drums in non-Latin music. Two metal drums are mounted on a stand along with bells and one or two cymbals. The timbale player also switches roles during a song, playing the sides of the drums (called the shells) a rhythm called “cascara” during the lower energy portions of the song (when the Bongo player plays his drum) and then moving up to the bell and cymbal during the high-energy portion. 

THE SALSA SONG

Putting these all together forms the complex rhythms of a salsa song. Beyond that, the song structure is often very much like any pop song with one or two verses, followed by a chorus section. In salsa, the chorus section is called the “mambo section” and it is the higher energy portion where the bells are played. It is also the easiest to hear the beats, which can be unfortunate since most songs do not start with a mambo section!

Singers sing the versus and during the chorus section, they engage in “coro/pregon” where a chorus is sung and then a lead singer often improvises during sections between the chorus to tell a story. It is the same structure of “call and response”, or antecedent/decedent, that makes up such a large portion of this type of music, dating back to the ancient African rhythms themselves such as Clave, which were the way tribes communicated from a distance – with calls and responses.

The horns play melodies too like in pop music and often play a repeating phrase called a “mona” during the mambo section of the song. All together you have a salsa song.

The samples below contains the elements described above together:

SAMPLE : Full band medium with counting

SAMPLE Full band medium without counting

With horns added and an arrangement, a full salsa song is exemplified with the sample below:

SAMPLE : Full Salsa Song

http://www.salsabyjake.com/rhythmtutorial.html