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Recordists must often bring their attention to a specific range of fre-quencies, or frequency bands, to identify some aspect of sound quality or equipment performance. This section will present a rough equivalent in musical contexts that can be used to develop this skill and more.

Many percussion-related sounds occupy a pitch area, not a specific pitch. These sounds are perceived as existing in an area between two boundaries. The boundaries may, at times, be unstable and changing in pitch and dynamic level, and secondary pitch area(s) may also be present.

These sounds are evaluated and defined by (1) the density (amount) of pitch information within the pitch area, (2) the width of the pitch area (the distance between the two boundary pitches), and (3) the presence of secondary pitch areas and the dynamic relationships of those areas.

Some sounds will have several, separated pitch areas. The different pitch areas of the sound will be at different dynamic levels and have dif-ferent densities (the amount and closeness of spacing of the pitch-infor-mation within the pitch areas). One pitch area will dominate the sound

and be the primary pitch area. The other pitch areas will be secondary pitch areas.

Evaluating the pitch areas of several percussion sounds will develop a number of important listening skills. Frequency and pitch estimation (recognition) will be refined, and the listener will take the skills of the last section to a more detailed level of perspective. The focus will now be on identifying pitch/frequency levels within the spectrum of the source—

using sound sources that allow us to approach this information in a more noticeable and higher level of perspective. This is a first step toward iden-tifying subtle aspects of sound quality (that will be greatly refined later).

Further, this study will be accomplished without the added tasks of a time line, as the graph will sum spectral information throughout the sound’s duration. The reader will also make some rough observations on dynamic levels. This skill will also be greatly refined later.

It is possible that pitch area analysis will be unlike anything the reader has done in the past. Few reference points will be available for the listener to draw upon, other than the pitch estimation skills acquired above. Difficulties and frustrations are to be expected, along with great satisfaction with acquiring a very useful skill that will be used and improved throughout one’s audio career.

To perform an analysis of pitch areas, sounds are plotted on a pitch area analysis graph. The graph incorporates:

1. The register designations for the Y-axis;

2. A space on the X-axis of the graph is dedicated to each sound instead of the passage of time (since this evaluation sums all information during the sound’s duration);

3. The pitch areas are boxed off in relation to these two axes;

4. The density of each pitch area designated by a number within each box that relates to a relative scale from very dense to very sparse; and 5. Assigning a number to the relative dynamic levels of pitch areas,

especially important to identifying the predominant (primary) pitch area (dynamics will receive detailed coverage in the next chapter).

Figure 6-4 presents the pitch areas of the prominent bass drum sound found in The Beatles’ “Come Together” (1 version) at 0:34.

The percussion sound is comprised of four pitch areas. The primary pitch area is the second from the bottom. It is moderately dense and is the loudest and dominant area. The density of the lowest pitch area is a bit more dense, but considerably softer. The area between 167 and 265 Hz is moderately dense and a bit louder than the lowest area, and not as loud as the primary pitch area. The highest pitch area (approximately 315–395 Hz) has a rather sparse density and is at the lowest loudness level of all four pitch areas. It is interesting to note that the lower boundaries of the

four pitch areas are nearly whole number multiples and harmonically related, but far enough away to create strong noise elements. These types of relationships are common for drum resonances and head vibrations.

The pitch area graph and the objective descriptions of density and dynamic relationships of the pitch areas, provide much useful and uni-versally perceived information about the sound. Meaningful communica-tion about this sound is possible with this informacommunica-tion.

Next, the Pitch Area Analysis Exercise (Exercise 6-3 at the end of the chapter) should be performed until the material is learned. The reader is encouraged to evaluate drums and cymbals of a variety of sizes directly from music recordings.

A number of percussion sounds from the drum solo of The Beatles’

“The End” appear in Figure 6-5. The reader can determine the dynamic relationships of the pitch areas and observe their densities. Study the example carefully, seeking to identify the boundaries of the pitch area,

First Number 5 Very Dense 4 Dense

3 Moderately Dense 2 Sparse

1 Very Sparse Second Number 5 Very Loud

4 Loud

Figure 6-4 Pitch area analysis of the bass drum sound from The Beatles, “Come Together.”

and confirm the density information presented. Once the pitch areas can be identified, the reader can observe the dynamic relationships of the pitch areas.

The reader will be able to apply the skills and concepts of pitch area to the recognition of frequency bands in critical listening applications.

The information for evaluating the states and changes of frequency levels will be directly transferred from the perceived pitch information. The skills gained through the recognition of pitch areas and frequency bands will later be directly applied to the evaluation of timbre and sound quality.

In fact, these pitch area analyses are rudimentary timbre analyses.

First Number 5 Very Dense 4 Dense

3 Moderately Dense 2 Sparse

1 Very Sparse Second Number 5 Very Loud

4 Loud

Figure 6-5 Drum sounds from The Beatles, “The End.”

A common critical listening situation is to compare two sounds.

Figure 6-6 compares the crash cymbal from two different songs. Notice the characteristics of the sounds through careful listening to identify pitch areas and their densities. From the graph we can see the areas are similar in location and nearly identical in their densities. Some areas have markedly different relative dynamic levels.

As skill increases, the listener will gradually come to understand and recognize slight differences present in the spectra of similar sounds.

Eventually the reader will arrive at the point where evaluations of the high hat and crash cymbal sounds from three different “Let It Be” releases can be compared (listed in the Discography). The reader is encouraged to listen carefully to these sounds. The sounds change within each song and are slightly different in each recording. The reader will notice many striking differences and perhaps a few of the many subtleties. These dif-ferences will gradually seem more and more significant. Ultimately, the

First Number 5 Very Dense 4 Dense

3 Moderately Dense 2 Sparse

1 Very Sparse Second Number 5 Very Loud

4 Loud

Figure 6-6 Crash cymbal sounds from The Beatles, “Come Together” and “Something” (both from1).

reader will recognize the sounds as very different and will perceive the details of their sound qualities.