Montag, 10. Juni 2019

Perfect Pitch Meter

Wouldn’t it be nice to know where you stand on the road to perfect pitch?
Having an indicator that can show you your progress towards perfect pitch helps you to recognize and improve your weak points.
Unfortunately, the definition of perfect pitch is very complex. Wikipedia redirects a search for the term “Perfect Pitch” to the page “Absolute Pitch.” In this way, perfect pitch is often used as a synonym for absolute pitch.
In my opinion, the term “perfect pitch” should be used for describing the precision of relative pitch. Let me explain:
Wikipedia states as one of the criteria for perfect pitch (absolute pitch): being able to sing a pitch in the equal-tempered system without having a reference tone.
Unfortunately, this definition combines two aspects of pitch skills:
1)    Matching a pitch perfectly
2)    Remembering a pitch perfectly
Matching a pitch perfectly
This aspect addresses relative pitch skills. If you can match a pitch perfectly when singing, then this is a relative skill, since you match a pitch you’ve heard with your voice. Now, matching a pitch has nothing to do with the equal-tempered system of frequencies. You can match a pitch that is off the equal-tempered system. In fact, there are other music systems in which you have to match other frequencies to be in tune. Even in the equal-tempered system, the pitch frequencies have changed several times: “The standard pitch has not always been 440 Hz. It has varied and generally risen over the past few hundred years“ (“The History of Musical Pitch in Europe“, Hermann von Helmholtz, referenced in the Wikipedia article “Equal Temperament“.)
Since to be/sing in tune is the most important aspect of harmonic music, relative pitch is independent of absolute pitch frequencies. Therefore, the term perfect pitch should be used to express a perfect match of any frequency.
To be able to match a pitch perfectly, you must be able to recognize deviations from a given reference frequency. This is a skill that can be trained and improved with appropriate feedback. Measuring the deviation-recognition ability does not only apply to recognizing deviations from equal-tempered frequencies but is valid for any frequencies.
This insight let to the development of a relative pitch meter (see my post “Relative Pitch Indicator”).

Remembering a pitch perfectly
The second aspect addresses absolute pitch skills. You must be able to remember the sounds of absolute frequencies. Since you are not allowed to hear a reference tone, you must be able to recall the sound of a pitch from your long-term memory. Now, we all can recall song-melodies. The question is how accurately – in relation to absolute frequencies – we remember the pitches.
Recall can be learned and improved too. For example, with exercises like “growing melodies”  – in which a melody grows by adding a new random note at the end and your task is to recall and replay the growing melody – you can train your pitch memory. Unfortunately, in a growing melody exercise, you will use also relative pitch skills, since you can build on the previously heard note.
To eliminate the relative pitch part, we must introduce a silence period. That means, before you are allowed to recall a note, there must be pitch-less period of a certain duration.
If we use the Wikipedia criteria, “Accurately sing a named pitch without a reference tone,” then we can – for a given silence period – measure your recall precision directly. A reproducible test can be built by letting you hear a tone – in your singing range – and after a specified silence time, requiring you to sing that tone back. The reproduction of the pitch through singing allows us to measure the deviation from the original pitch. If we need to match the pitch within a predefined precision, then the silence period – within which we are still able to reproduce the pitch correctly within the required precision – can be used to express our pitch memory as the silence period in seconds.
This insight was used to develop an absolute pitch meter (see my post “Absolute Pitch Indicator”).
Despite the title “Perfect Pitch Meter,” no perfect pitch meter has been presented. However, by assessing the values of the relative pitch meter and the absolute pitch meter, a kind of a perfect pitch meter could be constructed.
The absolute pitch meter seems to be nearer to capturing the most difficult part of the Wikipedia definition for perfect pitch. On the other hand, hearing relative pitch distances accurately is much more important for music. Harmony means that the pitches relative to each other harmonize. Therefore, a relative pitch meter is much more useful than an absolute pitch meter. Progress in relative pitch has a direct observable influence on a performance.
Nevertheless, absolute pitch training is memory training and helps to overcome forgetfulness. However, it is very exhausting. For example learning a growing random number is very tedious and therefore abandoned quickly. The merits are not easily visible. The same is true for acquiring perfect pitch.
Is the effort needed to achieve progress —compared to the merit— the killing factor for acquiring absolute pitch?
According to the article “Acquiring Absolute Pitch in Adulthood Is Difficult but Possible (July 2018)”, the authors Yetta Kwailing Wong, Kelvin F.H. Lui, and Ken H.M. Yip, believe that the findings of their studies suggest that absolute pitch continues to be learnable in adulthood. So, why then don’t we see more people that acquire absolute pitch? The simple answer that the merits don’t outweigh the effort deserves a closer look.
What is “Pseudo Absolute Pitch”?
To my knowledge, there exists no definition for the term “pseudo-absolute pitch.” The term is used to express that there is always a noticeable difference between acquiring absolute pitch abilities in childhood and adulthood. While this may be true, it does not prove that the brain is unable to acquire “real” (indistinguishable) absolute pitch at any age. To support this thought, let us look at the ability to learn a foreign language. You can start learning a foreign language any time after childhood. The question is: How perfectly can an adult learn a foreign language? Can an adult learn a foreign language perfectly at all? To answer these questions, there are three main topics that we have to honor:
  1. The term “perfect” is always relative to subjective interpretation.
  2. Learning exposure: The environment where the learning takes place (e.g., a foreign country) is important
  3. There is limited available time
Since the first aspect is subject to personal preferences, I will not dive in deeper. I will only say that the fact that a person who has learned a foreign language can get better marks on tests than natives does not mean that his language understanding is better than that of a native speaker.
The second aspect points out that, for learning a foreign language, moving to the country of the language’s origin makes a huge difference. The constant exposure to the language has a great influence on learning. However, an iron will is still necessary to overcome shortcomings. Especially, to get rid of one’s own native accent is not easy. In this way, active training is needed. In contrast to the constant language exposure, acquiring perfect pitch is much more difficult, since there is no permanent utilization of absolute pitch references. As I mentioned before, music is always based on relative pitch. Therefore, it will be much more difficult to acquire absolute pitch than to acquire a foreign language perfectly to the point where native speakers can no longer differentiate the persons origin.
The third aspect, a limited lifetime, makes it clear that a 70-year-old person probably does not have the chance to learn a foreign language perfectly. But here, we must recognize that even a 70-year-old person can still make progress in acquiring a foreign language. If we assume that acquiring perfect pitch has a lot in common with learning a foreign language —both are based on audio (listening and expressing) —  then the question comes down to this: If it is possible to learn a foreign language perfectly in adulthood, why shouldn’t it be possible to acquire perfect pitch? To answer this last question we must find out how our brain functions.
How does our brain work?
To answer this question, I propose the following thought experiment: Let us assume that a person stops aging after 70 and lives for another 1,000 years.
In this case, I will argue that after 1,000 years, a person living in a foreign country will be as native as a real native, since during these 1,000 years, the person will make progress, even learn all the customs. And if the person is actively working on his or her accent, then he or she will no longer be distinguishable from natives, especially since during that period, the use of the vocabulary will change —new words will be added, and other words will vanish. This person will even be part of this process and help form the language.
If this thought experiment is true, then this implies that the brain is built for learning perfect pitch too. There are no magical wirings in the brain that forbid the brain from acquiring perfect pitch. If our goal is to understand how the brain works, then we should concentrate on looking at why the brain starts blocking accepting new concepts. One reason could be that the brain feels “overloaded,” like if you have eaten enough and your desire to eat stops. That is, if the brain no longer recognizes a need to learn a new concept, then the brain is no longer willing to transfer information from short-term to the long-term memory. The brain tries to safeguard our long-term memory from overloading. It is obvious that the capacity of our long-term memory is limited. Therefore, it seems plausible that during our evolution, a sufficient reserve for fast adaption proved to be a lifesaver. Thus, the brain starts to delimit the transfer from the short-term memory to the long-term memory. Concepts that do not bring visible progress (or reward) during a certain period simply do not get transferred.
The important lesson we should take from this thought experiment is that the brain never changes its essential learning behavior. You can still learn anything you want at any age if you have enough energy and time to do so. And the second thing we should honor is that clear, fast, rewarding feedback is a strong supporter in learning.
For acquiring absolute pitch, this means that our brain needs direct feedback to see where we stand so that we can observe our progress, and therefore, the information transfer to the long-term memory does not get blocked. We know that relative pitch deserves more attention and that relative pitch shows faster progress towards musicality. We also know that we do not have permanent exposure to using absolute pitch frequencies as references. For making progress in learning musical concepts, relative pitch will always be dominant, since during musical activity, we always have to adjust relative to other instruments. Even without other instruments in a melody we have to make sure that the tones are relative in harmony to each other. So, it will be very difficult to acquire absolute pitch, if we do not already have a good sense of relative pitch. Therefore, we must learn to listen carefully for relative pitch distances first, before we can start to memorize absolute pitch frequencies with the required precision.
Because we can derive a similarity between learning absolute pitch and our language-learning thought experiment, it should be possible to acquire perfect pitch provided that we are given enough time and learning exposure. The fact that our brain will prioritize learning relative pitch just makes it very difficult to acquire absolute pitch. Most people will give up before reaching the necessary precision and speed even for relative pitch.
The first thing you should do is perfect your relative pitch hearing abilities. Since relative pitch deviations must be corrected immediately, the skill of detecting pitch deviations is essentially a speed accomplishment. Since the relative pitch meter attaches importance to reaction time, it can be used to achieve improvements in this direction. The goal should be to reach a level where recognition of relative pitch distances should become innate.
Second, the observable decline of improvement in the absolute pitch training undermines the argument that “the effort vs. the merit is the killing factor” for acquiring absolute pitch, and not the “you have to be born with it claim” is true. To further support this claim, I need about 100 persons who are willing to spend 20 minutes a day for a period of 100 days. Please download the program SamePitchPlease and take 20 minutes each day to document your pitch recall ability progress, thus collecting data on your progress towards absolute pitch. In this way, the absolute pitch meter will collect information about the starting absolute pitch level, the improvements made, and the observable slowdown of improvement. The speed of improvement is the critical point for motivation. If the absolute pitch level cannot be improved within a reasonable time, then people will start to give up. If you give up before the 100-day period, please let us know the reason in the comment section of the export dialog in the SamePitchPlease program.
Together, the relative pitch meter and the absolute pitch meter show you where you stand on the path to perfect pitch. Don’t be disappointed if your score is low —this only shows that there is room for improvement.
Call to action
Even though a perfect pitch meter could be constructed from the results of the relative pitch and absolute pitch meter, it does not make sense, since to motivate someone, direct evaluable feedback in relation to the effort made is necessary. By measuring two aspects separately, you can better see the effect of your effort towards each of the goals: acquiring relative pitch abilities and acquiring absolute pitch abilities. Combining two meters into one meter blurs the assignability of an effort to an outcome.
The absolute pitch meter does not really help you to improve your musicality. Musicality is always a relative task –you must be in harmony relative to a given key. So, is an absolute pitch meter useless? No it can help us to understand how the brain works. Absolute pitch is a very good field for understanding/discovering the functioning of short/long-term memory. Therefore, the observations made during a 100-day period with the absolute pitch ability test would not only help to prove/refute the hypothesis that the effort vs. the merit is the killing factor for acquiring absolute pitch, but also give some inside data on the functioning of our short- and long-term memory. The level where you start is not an issue –everybody will make progress just by the effort they put in. But everybody will also slow down in the progress curve. And then it gets boring. The aim of this call to action is to document this slowdown in acquiring absolute pitch with the program SamePitchPlease. For relative pitch, the program PitchBlitz can be used to document the learning behavior.
So, please download the free program SamePitchPlease ( to start your absolute pitch training, or PitchBlitz ( to start your relative pitch training. After 5 days please export your statistics and send the exported file to felixthecat @ This way, I will know that you have started the training. After finishing the100-day training period, please, send me your statistics report again. Of course, if you give up earlier, I would appreciate if you send me your current statistics anyway (preferably with a short comment on why you gave up).
When I get five emails with a 5-day starting statistic, I will publish a table ( showing the participant number, the starting date and the starting score. The table will contain other columns —initially empty that will show the score after 100 days, or if you send me an intermediate reportyour intermediate score and the number of training days you have completed. You do not have to send intermediate reports. However, sending me the first report after 5 days should motivate others to also start to explore their relative/absolute pitch capabilities, because they can see that others have started (to see nothing feels like being a lonely fighter, and if you give up before the 100-day period, it is very unlikely that you will send in your finishing score). If you finish the 100-day period, I appreciate when your sending me the final report. In case you give up earlier, sending me your last report is also highly appreciated. In this case, the table will be updated with the last score and completed number of training days along with the information you reported for the reason for giving up (via clickable choices or comment).
The data I receive will be rendered anonymous, so your name will never occur in a statistic. Your email address will never be used except to check back in case of ambiguities.
Thank you for your support


Dienstag, 13. November 2018

Relative Pitch Indicator

Building a relative pitch meter

After developing an absolute pitch indicator, I asked myself "Shouldn’t there be a more general way to measure the sense of relative pitch?" After all, the expressions “I have good relative pitch,”  “I have excellent relative pitch,” and “I have bad relative pitch” are not quantitative statements.

Because relative pitch is the essential thing in musicality, I should have developed such an indicator in the first place. The idea that you cannot acquire absolute pitch after a certain age, is in my opinion not helpful in improving one's musicality. Therefore, the idea of taking away the mystique of perfect pitch arose. But only after developing a continuous absolute pitch indicator did I realized that the advantages of having a similar indicator for relative pitch, is too.

There are numerous interval test programs that can tell you how many out of a certain number of  intervals you've guessed correctly. Isn’t that good enough? After all, you get enough feedback to continue your training and improve your percentage ratio.

In most cases, the feedback is very helpful, because you know that the percentage was for a particular interval or intervals. For example, you may have tested major thirds, perfect fifths, or a combination of both. Or, in the best case, you do a test of all intervals. While such a percentage provides an overall view of relative pitch, it is not useful for beginners. Beginners are better off receiving feedback on specific intervals. This allows them to train specifically on those intervals where they need improvement. More importantly, they can better track their progress.

Why, then, should we have a relative pitch indicator?
There are two main reasons for developing a relative pitch indicator: precision and answering speed. Additionally, the indicator provides the advantage of music system independence.

Interval Precision
What exactly is relative pitch? To identify an interval, you must recognize pitch distances. That is, you must recognize that the tonal distance between a minor third and a major third is smaller. However, if you think that smaller distances are more difficult to recognize than larger distances, then you are wrong. This lies in the relationship between tones and overtone creation. Normal tones will always create overtones, and these overtones follow a simple pattern: the path of least resistance. If you pluck a string, the string will start to vibrate with its fundamental frequency. The first overtone that gets generated is always the octave and its wavelength corresponds to half the length of the string. In other words, the wavelength fits twice within the original length. The next overtone is the perfect fifth and its wavelength fits three times within the original length. Now, since the first overtone is an octave, we also hear a perfect fourth, since the perfect fourth is the inverse interval of the perfect fifth. For more information on this topic, see my video: Absolute and relative pitch – inside our methods.

In this way, pitch distance discrimination has two components: the tonal distance and the overtone relationship. While for the octave, the distance is usually the main identifier, for the perfect fifth and the perfect fourth, the overtone relationship makes the distinguishing process difficult. In fact, for most people distinguishing perfect fourths and perfect fifths is an extremely difficult task. Therefore, for learning purposes, it makes sense to follow an interval training pattern.

However, as a general measure we should still use pitch distance alone as the relative pitch indicator. How do we describe the difference between someone who has “a good sense” and someone that has “an excellence sense” of relative pitch? To answer this question, we have to go deeper – beyond the precision of half-steps. That is, we must measure pitch distance deviations. In this way, measuring pitch distance is the only way to determine relative pitch discrimination ability.  

Answering Speed
Unlike absolute pitch, it is generally accepted that relative pitch can be acquired. So, assuming that you have acquired relative pitch, then the recognition speed is still a criterion to differentiate or grade your ability. For relative pitch, speed is everything: You should continually improve relative pitch recognition speed until it is innate. Therefore, answering speed should be part of a relative pitch indicator.

Music system independence
When we speak of relative pitch, we usually mean intervals in the equal-tempered system. Thus, one must know the interval names of this system. However, there exist other music systems around the world. Furthermore, people without a musical education can also discriminate pitch distances; they just cannot name the intervals because they lack basic music theory.

Since all music systems recognize the octave, dividing the octave into equal small steps makes it possible to measure pitch distances. In the equal-tempered system, the octave is divided into 1,200 small steps. A half-step, then, consists of 100 such small steps. In the equal-tempered system, deviations from standard frequencies is given in cents. Therefore, one small step equals 1 cent. For the remainder of this post I will use the term "cents" for pitch distance statements.

This music system independence allows for the measurement of general pitch distance and is thus suited for a general relative pitch indicator.

Idea and development
If we want to measure and quantify relative pitch, we must first identify the main quality of relative pitch. When I developed the absolute pitch indicator, I started with the assumption that everybody has absolute pitch, but some are just better than others. So, all we have to do is find a continuous measure to describe that ability. Since most people do not have absolute pitch, I have to bring them into a framework where I can say, "You have this degree of absolute pitch." Therefore, I did loosen the definition of absolute pitch. For example, if someone is never more than a half-step off from the correct answer, then this person – in my system – has absolute pitch. This assumes the absolute pitch test would be done only with whole-steps instead of half-steps. If we go even further in loosening the required recognition precision – to an octave, for example – then we can grade all possessors of non-absolute pitch. But I can also go in the other direction by defining perfect pitch as the ability to discriminate pitches by a third of a half-step. That is, there are now 36 tones to identify in an octave. A sample answer for a tested tone, then, would be "This is an 'A' plus a third of a half-step.” Now some people who have absolute pitch according to the current perceived meaning of absolute pitch would start to fail the test for the narrower definition. If we were to go even further by accepting deviations of only fractions of a cent, then at some point everybody would fail the test (e.g., if you must be able to express tones to a precision of 0.1 cent – such as: this is an “'A' plus 34.7 cents.“). For absolute pitch, measuring accuracy is, in my opinion, not the most relevant criterion, so, I decided to keep accuracy at a fixed level, and use the retention-time as the unit for the indicator. Nevertheless, the loosening of the accuracy was the first step toward the absolute pitch indicator.

Using a similar approach for a relative pitch indicator, I will start by testing to see if one can successfully identify large pitch distances. In this way, I can already start to grade people with a poor sense of relative pitch. In addition, I will take the tested range and measure the answering speed. This allows me to grade even more precisely. Going beyond the precision of half-steps in the grading lets you see your “cushion” and gives you confidence. Therefore, the main criterion will be the pitch distance, and the unit of the relative pitch meter will be cents. For example, if you are able to identify pitch distances to a third of a half step, then your relative pitch indicator is 33 cents. In other words, you can differentiate an interval from another interval that deviates by a third of a half step.

When I introduced the program listening-ear-trainer (March 2013), I also added – as a by-product – a learning box for intervals. Instead of absolute pitches, intervals are used as the “words” to memorize. A learning box is usually used for vocabulary training. Since, listening-ear-trainer is a training program, it is not suited for an evaluation test. Moreover, it is limited to pitch distances of a half-step.

So, after introducing the absolute pitch indicator, the idea for a general indicator for relative pitch was born. It is important to note that both indicators are independent of any particular music system and that the programs can also be used by non-musicians to grade them-self. This feature makes it easy to evaluate the success rate of any training program. Before releasing the program Pitch Grid Test (October 2018), I introduced the program PitchBlitz (June 2018), which is based on the same grid layout as the test but has additional training options. The test returns a continuous indicator for the relative pitch ability expressed in cents.

Defining the test and metrics
Pitch Grid Test measures the ability to distinguish pitch distances within a predefined precision. Thus, the distance itself is not part of the evaluation, only the ability to discriminate that distance within the given precision. That is, you must be able to differentiate a pitch distance from a pitch distance that is larger or smaller by the amount of the given precision.

Relative pitch tests can be done in two ways: harmonically or melodically. In a harmonically played interval, both notes are played simultaneously. In a melodically played interval, the notes are played one after the other. Harmonic intervals are simpler to test, since no melodic time delay has to be defined. Furthermore, in the melodic interval test, an additional component comes into play: The participant must keep the reference tone in mind until the second note is played. However, since relative pitch recognition also implies melodic intervals, and the main distinction between absolute and relative pitch is the presence of a reference tone, I prefer to use a separate distinguished reference tone for the test.

In addition to the pitch discrimination precision, the maximum time used to answer is also measured.

The result of the relative pitch test is expressed in cents as the amount of deviation you are still able to recognize.

The test procedure
To avoid side effects, the test should use (pure) sinus waves. In addition, pitch distance deviations should be created by calculating the appropriate frequencies. Human interactions would not be precise enough. Therefore the test can only be performed using a computer.

The test procedure is as follows: 
  1. The person who wants to test her or his ability choses a frequency range (three or four octaves ) and a starting pitch deviation (from 1,200 downto 7 cents) to be tested.
  2. The computer plays a random reference tone.
  3. After a short pause the computer plays a tone that must be identified, whereby the tone to identify is multiple times the chosen pitch deviation away from the reference tone.
  4. The candidate has to select the correct tone in a grid.
  5. If the candidate selects the correct tone, then the test continues with another tone to identify. No new reference tone is played. The last heard tone is the new reference tone.
  6. If the candidate selects a wrong answer, then the selected tone is played followed by the correct tone, and the candidate is given one more chance to pass the test. If he/she fails a second time the test is finished and the relative pitch indicator is calculated.
  7. If the candidate does not answer within six seconds, then this is recorded as a wrong answer.
  8. After ten tones have been tested, the test continues with a smaller pitch distance deviation.
  9. The test ends when you make your second error, or when you have passed the test with a pitch deviation of 7 cents.

Since a general pitch distance test has to go beyond half-steps and must be independent of any music system, building such a system based on the Western equal-tempered system does not seem like the ideal solution. However, we can still use equal-tempered frequencies as base reference points and conduct arbitrary-distance tests from these points. Using equal-tempered frequencies as starting points does not really limit our measuring quality, as we can still measure pitch distances outside of the equal-tempered interval system.
Thus, my proposal is to use a pitch grid based on the equal-tempered system. We can measure pitch distances beyond the precision of half-steps by making the grid resolution finer. If we also use reference tones that deviate from the equal-tempered frequencies by the amount of a grid resolution, the test will be generalized enough to confirm pitch distance recognition independent of the equal-tempered system

Next steps
Please let me know what you think about my proposed relative pitch indicator/relative pitch meter. Do you know of any other approaches for measuring relative pitch that also allow for measuring the sense of relative pitch in non-musicians? Also, do you have ideas for improvements?

Sonntag, 4. November 2018

Absolute Pitch Indicator

Building an absolute pitch meter

Wikipedia shows the following definition for the term absolute pitch:

"Generally, absolute pitch implies some or all of the following abilities, achieved without a reference tone:
   Identify by name individual pitches (e.g. F, A, G, C) played on various instruments.
   Name the key of a given piece of tonal music.
   Reproduce a piece of tonal music in the correct key days after hearing it.
   Identify and name all the tones of a given chord or other tonal mass.
   Accurately sing a named pitch.
   Name the pitches of common everyday sounds such as car horns and alarms.
   Name the frequency of a pitch (e.g. that G4 is 415Hz) after hearing it."

Unfortunately, the definition “some or all” is confusing and leaves room for interpretation. A simpler definition given at the beginning of the Wikipedia article says "Absolute pitch (AP), widely referred to as perfect pitch, is a rare auditory phenomenon characterized by the ability of a person to identify or recreate a given musical note without the benefit of a reference tone." This sentence is also ambiguous since it also contains an "or."

This ambiguity makes it very difficult – if not impossible – to answer this question with a "Yes, you have it" or "No, you don’t have it."  

This situation is aggravated by the fact that the Wikipedia’s definition is not precise and no other official definition exists. For example, an individual might be able to recognize notes in a very limited range or is capable of naming simple chords, yet may fail to identify very complex chord names because of the lack of knowledge in music theory. Or, how much time is allowed for recognizing a note or a chord name? Must the answer be given within a second, or is figuring it out in a minute still accepted to count as an absolute pitch possessor?

On the other hand, how important is it to know if you have absolute pitch or not?

Of course, having the ability to identify absolute pitches is fascinating. However, music lives from change. That is, pitch changes relative to other notes. Absolute pitch associates a name to a particular frequency, thus is isolated. Creating harmony in music involves relations to other notes.

Being able to recognize notes, intervals, chords, and keys requires knowledge of the underlying musical system. Detecting keys or chords requires several notes; detecting intervals requires two notes. These notes are then set in relation to each other. The underlying music system assigns these constellations interval names, chord names, or a key name. Therefore, these abilities have more to do with music theory and relative pitch skills than with absolute pitch abilities.

This is also the main reason why it is generally accepted that relative pitch is more important than absolute pitch. Many well-known musicians did not have absolute pitch. Or maybe they just did not care about it because harmony in music is always relative, and absolute pitch frequencies are irrelevant for that matter.

Why, then, should we have an Absolute Pitch indicator?
The only reason I can think of is to have a musical goal. Ear training is an important aspect for any music student. There are our ears with which we can judge if we are in tune with others or not. If we are playing a solo, the ability to keep a fundamental note over a longer period in our mind is a useful skill: it prevents us from drifting off the key.

Not having a single, continuous indicator for absolute pitch makes it difficult to bring absolute pitch in line with a training program. The road to absolute pitch may be long, and only a "Yes, you have it" or "No, you don’t have it" answer does not leave room for a step-by-step progress.

To make gradual progress, we need better feedback. We can break up the Wikipedia criteria for absolute pitch in separate tasks and measure progress in each category. However, we still have to guess our progress toward absolute pitch. More importantly, how do we measure the criterion: "identify a pitch without a reference tone"?

The main problem here is "without a reference tone." If we are given a reference pitch and then listen to a piece of music, chances are that we still can remember the reference tone after the piece has finished. This is because we stay in a musical context. Therefore, we would solve absolute pitch questions after the piece has finished still through relative pitch skills.

To overcome this problem, we need to define a musical absence time, before we can answer absolute pitch questions. Tests have shown that after a quarter of an hour of musical absence, in most cases, the reference tone has vanished – is no longer accessible through our short-term memory.

Now, this restriction of a mandatory musical absence makes it nearly impossible to develop a test for testing the absolute pitch skill “recognizing a pitch without a reference tone”

Even so, we have good possibilities for measuring the other criteria for absolute pitch; we are still missing a method for measuring pitch retention abilities. Since “without a reference tone” is where people have most difficulties, the task of an absolute pitch indicator will be providing a pitch retention metric.

Directly measuring retention abilities is difficult since any test taken will interrupt the retention process. Thus, you would have to start measuring with a very large time, and if you fail then you would have to restart the test with a decreased time period until a successful feedback is generated. Such a test would be very long and therefore unpractical.

However, we can speed up this measurement if we can measure how pitch retention deteriorated during a specified time. To develop a continuous indicator, we must depart from the idea that we can only measure absolute pitch ability without a reference tone, if that "without" means a musical absence of fifteen minutes or more. By testing at lower time periods, we can get a picture of pitch retention deterioration.

Measuring how long you can retain a pitch with precision will complete a musical test. Being able to retain a pitch for a longer time has many positive implications on musicality. Therefore, an absolute pitch indicator still has its justification in a musical evaluation process. Trying to improve this indicator is a valid musical goal, even if we do not achieve absolute pitch as defined by Wikipedia.

Idea and development
In Wikipedia, the term perfect pitch is redirected to absolute pitch. This bringing together of the two terms is unfortunate. Perfect suggests that no errors are allowed. Perfect pitch implies many other abilities that are related to pitch. This implication has led to the definition of absolute pitch that there is no simple way of testing this ability. As a consequence, numerous rumors about absolute pitch have emerged. The biggest rumor is that you cannot acquire it: you must be born with absolute pitch. Since the requirements are not clearly defined, some people will not accept progress towards absolute pitch and will speak of pseudo absolute pitch, if for example; someone learns to identify pitches after singing a reference tone. They argue: It takes too long: it must be immediate. It must be magic. Unfortunately, this "Yes" or "No”"view is not helping people to see absolute pitch as a goal worth pursuing. Accepting imperfection and using a continuous indicator could make absolute pitch training a challenge and lead to a better ear.

The assumption that absolute pitch can be learned like foreign languages has led to the development of the program Listening Ear Trainer. Both absolute pitch and foreign languages use voice to express an idea. Both rely on retaining sound patterns in memory for references and analyses. Therefore, it stands to reason that absolute pitch can be learned the same way foreign languages can. The product Listening-Ear-Trainer (March 2013) introduced the learning box—used for vocabulary training—for learning absolute pitches. Keeping an eye on the precise pitch (singing) reproduction improves the retention skills and confidence in your musical discrimination ability.

Since no silence period between exercises in Listening-Ear-Trainer is mandatory, the training is not really for absolute but relative pitch. Therefore, in August 2015, I released the program TuneCrack. A direct application of keeping a pitch in mind is during the tuning process of an instrument. Therefore the idea was: Cracking the tuning problem by giving people a training program to increase their pitch retention skills.

The program TuneCrack recommends internalizing a pitch by taking it over to your voice. However, singing is not mandatory since only the precision-identifying ability is tested.

Since I believe that singing is the closest way you can get to music, I searched for a method to get a reliable way of measuring what I think is the most important criterion of absolute pitch: accurately sing a named pitch without a reference tone. This criterion includes singing and accurate pitch retention. The result was the introduction of the program SamePitchPlease (May 2016).

To improve the pitch retention training, the programs TuneCrack and SamePitchPlease introduced a silence period. However, these two programs are training programs that guide you through incremental exercises to better performance. If we want a tool that measures an individual’s absolute pitch ability in a more general way, then we have to build an absolute pitch meter that can be evaluated through a single test.

Restricting the program SamePitchPlease to four notes and a 25-cent deviation led to the Pitch Ability Test (November 2016), which returns an indicator on the pitch retention and reproduction ability. Both abilities are required for absolute pitch; therefore, the indicator can be used as a continuous measure for absolute pitch instead of only a "Yes, you have it" or "No, you don’t have it" answer.

Defining the test and metrics
The Pitch Ability Test defines the ability to reproduce a given pitch after a specified time period within a frequency precision of 25 cents as the measure. Thus, the Pitch Ability Test fixes the note accuracy for the reproduction and uses only the time as an indicator.

As with any test, the more precise a result should be, the more time is needed to determine the result. Therefore, a careful selection between time and accuracy should be considered. In the Pitch Ability Test, a decision to keep a single evaluation below 20 minutes was made. This limits the number of tones that can be tested during that time frame. Since the test should also prove that you can locate non-tested tones over a larger range, the test requires four different notes. Having four notes as fixed points ensures that you can orientate yourself by building distances between the tested notes and the directions: up or down.

The restriction of keeping a single test below 20 minutes leads to a maximum of 4 minutes for each note. That is, the best result you can get for the Pitch Ability Test is 4 minutes. While longer times can be easily measured, increasing the time does not make sense. Most people will have difficulty reaching this 4-minute limit—without training anyway. However, to make it clear that you have reached this 4-minute limit, and probably can reproduce pitches way beyond this point, the 4-minute point has a special name: Felix’s Pitch Point.

The result of the Pitch Ability Test is the silence time between the sounding of the reference sound and the accurate reproduction of the pitch with your voice. Pitch ability is expressed in seconds.

The test procedure
The requirements for administering the test are a stopwatch and a person with a good ear. This person  does not need to have absolute pitch. Playing the correct note on an instrument and comparing the pitch with the sung note can evaluate accuracy.

The test procedure is as follows:
  1. The person who wants to test his or her ability tells the tester four different notes that he or she thinks he or she can sing well and announces the period of silence for which he or she wants to take the test.
  2. The tester plays the first note for about two seconds.
  3. The tester starts the stopwatch.
  4. The person taking the test is allowed to sing back the note immediately for about two seconds. No feedback is given.
  5. The tester monitors whether no pitched sounds can be heard during the following period of silence.
  6. About five seconds before the announced test time is due, the tester signals to the candidate (with a visual sign or non-pitched sound) that he or she should prepare for the singing back of the note.
  7. When the time is due, the candidate should sing the note steadily for about a second. The tester listens carefully, compares the sung pitch with the original pitch, and decides whether the pitch did not deviate more than 25 cents from the original pitch.
  8. The tester repeats steps 2 to 7 for the remaining three notes.
  9. If the candidate succeeds with all four notes, then he or she has fulfilled the Pitch Ability Test for the chosen period of silence.

To determine pitch ability, the test uses an unconventional approach: the retention time gets measured in a similar way as the height in high-jump sports gets measured. This approach allows you to measure the retention time of the pitch with enough precision. If you select a low-enough time, you will always pass. If you come to your limits, the results will start to vary. Reaching Felix’s Pitch Point is not easy, but to acquire absolute pitch (or perfect pitch), you must pass this point. Therefore, the Pitch Ability Test is a useful tool for giving you feedback on where you stand on the road to absolute pitch. Most people who want to acquire absolute pitch are far away from Felix’s Pitch Point; thus, they can improve their ability.

A computer-based implementation
Since the wait—until you are allowed to reproduce the pitch—is very boring for the tester and the determination of the pitch accuracy is often non-neutral, a computer-based implementation of the procedure was made. The program Pitch Ability Test executes the above-described procedure and automatically suggests that you take a test for a higher time limit if you passed all four notes. This procedure is similar to that in high-jump sports, where you set your targeted goal and continue until you fail. Therefore, you should select your silence period with care. Starting with a very short period may fatigue and hinder you from reaching your best performance. Starting with a very long period poses the risk of getting no result at all.

Next steps
Please let me know what you think about my proposed absolute pitch indicator/absolute pitch meter. Do you know other approaches for measuring absolute pitch? Or do you have ideas for improvements?