Basic Musical Concepts - Beat, Rhythm, Melody and Harmony
Although tones in a melody sound successively in time, they can convey the sense of harmony, which is a relationship among simultaneously sounding pitches. It just means "the relationships between different pitches". Of course that interpretation only makes sense if the words are describing something that is actually. In music, harmony is the use of simultaneous pitches (tones, notes), or chords. chord member that creates a relatively dissonant interval in relation to the bass.
Vertical red lines demarcate chord spans, and horizontal lines indicate the pitches belonging to the chords. Chord annotations are based on both the melody and the accompaniment. To investigate the effect of trace prolongation across chord spans, we compared the traces at chord pitches and nonchord pitches within individual chord spans regardless of the origin of the traces.
The difference between the total trace durations for chord pitches and the total trace durations for nonchord pitches was taken as the perceptual salience of the annotated chord in the model's response. To evaluate the model's contribution to chord estimation over note durations, the difference in trace duration was then compared to the difference in total note duration between chord tones and nonchord tones in each chord span.
Methods The simulation data obtained for Test 1 were used for the analysis of individual chord spans. For each annotated chord span, trace durations and note durations were summed for chord pitches and nonchord pitches separately. The chord boundaries used for calculating trace durations were shifted forward by 40 ms to reflect the typical rise time of Layer 2 oscillations after the stimulus onset.
For each chord span, the differences between chord tones and nonchord tones in total trace duration and total note duration were calculated. A t-test was performed to determine whether the trace duration differences and the note duration differences are significantly different. Results and Discussion Figure 5 top shows the trace duration difference and the note duration difference for each chord span in the theme of K. The graph reflects our observations above.
For the second chord span, the trace duration difference is greater than the note duration difference meaning chord pitches are more emphasized in the model response than in the note durationswhile it is the opposite for the third chord span chord pitches less prominent in the model. Difference between chord pitches and nonchord pitches in total trace duration and total note duration within each chord span in Mozart Piano Sonata, K. The top panel shows a single simulation run with the entire melody, and the bottom panel shows simulations for individual chord spans run separately.
CT and NCT denote chord tones and nonchord tones. Considering all chord spans in the seven Mozart melodies, trace duration differences and note duration differences were significantly different [paired-sample t-test: This suggests that, overall, the dynamical model's response can provide a better basis for chord estimation than note durations. Mean difference between chord pitches and nonchord pitches in note duration, trace duration in single simulations and trace duration in segmented simulations, averaged over all chord spans in the seven Mozart melodies.
Trace Durations within Segmented Chord Spans Despite the overall advantage of trace duration over note duration, there are chord spans for which trace duration performs worse than note duration see Figure 5top. As discussed above, the prolongation of pitch traces across chord boundaries could result in less accurate chord representations.
This issue points to the importance of segmentation in chord estimation. Previous studies have shown that the accuracy of chord estimation can be improved by synchronizing analysis frames to the beat of the music being analyzed, which tends to align with harmonic changes Bartsch and Wakefield, ; Bello and Pickens, We tested whether chord estimation based on the pitch memory model could be improved by using segmented stimulus signals.
Instead of running the model for entire melodies, we chopped the melodies into individual chord spans and ran the model for each segment separately.
- Rhythm / Pitch Duality: hear rhythm become pitch before your ears
- 1 The Problem of Music
This would prevent previous oscillatory traces from extending into the current chord span because each simulation starts anew from small random initial values. Methods A separate stimulus signal was prepared for each chord span in the Mozart melodies total segments; see General Material and Methods for the general procedures of stimulus preparationand the model was run for each individual segment separately.
As was done for Test 2, the total trace durations and total note durations for chord pitches and nonchord pitches were calculated for each chord span. A t-test was performed to determine if trace duration differences and note duration differences are significantly different in segmented chord spans.
Results and Discussion Figure 5 bottom shows trace duration differences and note duration differences for the segmented simulations of K. It can be seen that the trace duration difference is either comparable or greater than the note duration difference for all chord spans. This shows that, as was found for previous methods using chroma-based features, chord estimation based on the pitch memory model can benefit from processing each chord span separately.
For this reason, usually tension is 'prepared' and then 'resolved',  where preparing tension means to place a series of consonant chords that lead smoothly to the dissonant chord. In this way the composer ensures introducing tension smoothly, without disturbing the listener. Once the piece reaches its sub-climax, the listener needs a moment of relaxation to clear up the tension, which is obtained by playing a consonant chord that resolves the tension of the previous chords.
The clearing of this tension usually sounds pleasant to the listener, though this is not always the case in late-nineteenth century music, such as Tristan und Isolde by Richard Wagner.
In a psychological approach, consonance is a continuous variable. Consonance can vary across a wide range. A chord may sound consonant for various reasons. One is lack of perceptual roughness. Roughness happens when partials frequency components lie within a critical bandwidth, which is a measure of the ear's ability to separate different frequencies.
Critical bandwidth lies between 2 and 3 semitones at high frequencies and becomes larger at lower frequencies. The roughness of two simultaneous harmonic complex tones depends on the amplitudes of the harmonics and the interval between the tones. The roughest interval in the chromatic scale is the minor second and its inversion the major seventh. For typical spectral envelopes in the central range, the second roughest interval is the major second and minor seventh, followed by the tritone, the minor third major sixththe major third minor sixth and the perfect fourth fifth.
The harmonious major triad is composed of three tones. Their frequency ratio corresponds approximately 6: In real performances, however, the third is often larger than 5: Measurements of frequencies in good performances confirm that the size of the major third varies across this range and can even lie outside it without sounding out of tune.
Rhythm / Pitch Duality: hear rhythm become pitch before your ears | Dan Tepfer
Thus, there is no simple connection between frequency ratios and harmonic function. The second reason is perceptual fusion. A chord fuses in perception if its overall spectrum is similar to a harmonic series. According to this definition a major triad fuses better than a minor triad and a major-minor seventh chord fuses better than a major-major seventh or minor-minor seventh. These differences may not be readily apparent in tempered contexts but can explain why major triads are generally more prevalent than minor triads and major-minor sevenths generally more prevalent than other sevenths in spite of the dissonance of the tritone interval in mainstream tonal music.
Rhythm is how you inhabit the pulse. Rhythm is what results of combining notes of different durations, sometimes coinciding with the beat and sometimes not. For example, if you can notice in Reggae or Ska music, the guitar or keyboards most of the times play, at times, exactly opposite to the beat.
And, last but not least: Usually, melodies are not just played alone by a solo instrument or a group of instruments playing the same thing.Fifth Harmony - All I Want for Christmas Is You
Very frequently there are 'lead' instruments which play melodies such as the voice, wind instruments, etc. Sometimes this can be done by one instrument such as guitar or piano, but other times by several instruments like didjes or brass ensembles. There are many types of relations between two or more notes played at the same time, but they can be classified into two main divisions: Consonance refers to a sense of stability and 'relaxation' experienced when listening to some harmonic relations.
Opposite to this, dissonance refers to the sensation of 'tension' or the feeling that something is 'unstable'.
Depending on the 'distance' between one note and another, we can classify their relations into consonant and dissonant. An interval is a number that represents the amount of notes between one note and another in the diatonic scale C, D, E, F, G, A, B - the one we all know without sharps or flats b.
This way, we call the interval C-G a fifth, and the interval E-A a fourth. There may be unisons where both notes played are the sameseconds, thirds, fourths, fifths, sixths, sevenths and octaves for example low C to high C. Intervals can be further named according to the amounts of 'steps' that they contain: A step is the distance between one note and another in the chromatic scale the 12 tones mentioned before with sharps and flats.