question: Why can people hum certain high/low notes but can’t sing them?
comment: Certain vowel sounds stress or tighten the vocal cords more than others. For example, singing a high pitched “ee” sound is harder than a high pitched “oh” sound. When you hum, your vocal cords don’t need to differentiate vowel sounds and instead produce sound in a more relaxed state.
passages: This phenomenon is apparently unrelated to musical training. The skill may be associated more closely with vocal production. Violin students learning the Suzuki method are required to memorize each composition in a fixed key and play it from memory on their instrument, but they are not required to sing. When tested, these students did not succeed in singing the memorized Suzuki songs in the original, fixed key.
  
  Section::::Scientific studies.:Possible problems.
   If the fundamental frequency of the underlying vibration is higher than a resonance frequency of the system, then the formant usually imparted by that resonance will be mostly lost. This is most apparent in the example of soprano opera singers, who sing high enough that their vowels become very hard to distinguish.
  
  Control of resonances is an essential component of the vocal technique known as overtone singing, in which the performer sings a low fundamental tone, and creates sharp resonances to select upper harmonics, giving the impression of several tones being sung at once.
   There may be a genetic locus for absolute pitch ability, which locus would suggest a genetic basis for its presence or absence. A genetic basis, should it exist, might represent either a predisposition for learning the ability or signal the likelihood of its spontaneous occurrence.
   Other factors, physical and psychoacoustic, affect the tuner's ability to achieve a temperament. Among physical factors are inharmonic effects due to soundboard resonance in the bass strings, poorly manufactured strings, or peculiarities that can cause "false beats" (false because they are unrelated to the manipulation of beats during tuning). The principal psychoacoustic factor is that the human ear tends to perceive the higher notes as being flat when compared to those in the midrange. Stretching the tuning to account for string inharmonicity is often not sufficient to overcome this phenomenon, so piano tuners may stretch the top octave or so of the piano even more.
   However, musical experience does not assist the ability to consistently match colors to tones. Against natural expectation, studies have found that possession of absolute pitch increased local variance in matching ability. One possible explanation for this is that because absolute pitch is subject to chance error, occasionally incorrectly inferred note names could compete with the pitch-induced color on particular trials. Another possibility is that people with absolute pitch can label tighter pitch recognition categories than normal, introducing a greater number of category boundaries to cross between distinct tones.
   Section::::Image properties.:Pitch.
  
  Humans retain a relatively strong auditory image for details in pitch, which can be improved with musical training. The development of cultivating an auditory image with absolute pitch, which is being able to determine a note upon hearing a sound, however, is dependent on childhood musical training and genetic factors. People are able to improve their discrimination of pitch; however, they cannot improve their detection. Auditory image pitch detection studies have shown that response time decreases when judging two high pitches as opposed to judging two low pitches.
  
  Section::::Image properties.:Loudness.
   A low pitch (also known as the pitch of the missing fundamental or virtual pitch) can sometimes be heard when there is no apparent source or component of that frequency. This perception is due to the brain interpreting repetition patterns that are present.
   In order to determine if Monica's disorder is amusia, she was subjected to the MBEA series of tests. One of the tests dealt with Monica's difficulties in discriminating pitch variations in sequential notes. In this test, a pair of melodies was played, and Monica was asked if the second melody in the pair contained a wrong note. Monica's score on this test was well below the average score generated by the control group. Further tests showed that Monica struggles with recognizing highly familiar melodies, but that she has no problems in recognizing the voices of well-known speakers. Thus, it appears that Monica's deficit seems limited to music. A later study showed that not only do amusics experience difficulty in discriminating variations in pitch, but they also exhibit deficits in perceiving patterns in pitch.
   She bought a cheap guitar, for 100 dollars, and learned 3 chords only before she stopped, frustrated, because of the annoying sound the cheap guitar made.
   To check guitar tuning, a guitar tech must be able to play major, minor, and other chords in a variety of keys. Even if the guitar has been tuned with an electronic tuner, the tuning still must be checked by ear, because the equal tempered tuning of a guitar can involve compromise. Guitar tuning can be affected by fret placement and wear, the angle of bridge angle, string age, and other factors. Thus, even if an electronic tuner indicates that a guitar is 100% "in tune," it may still need minor adjustments which are made by ear. 
   I was getting so heavy that even my vocalizing was getting heavy. I was tiring myself, I was perspiring too much, and I was really working too hard. And I wasn't really well, as in health; I couldn't move freely. And then I was tired of playing a game, for instance playing this beautiful young woman, and I was heavy and uncomfortable to move around. In any case, it was uncomfortable and I didn't like it. So I felt now if I'm going to do things right—I've studied all my life to put things right musically, so why don't I diet and put myself into a certain condition where I'm presentable.
   Missing fundamental
  
  A harmonic sound is said to have a missing fundamental, suppressed fundamental, or phantom fundamental when its overtones suggest a fundamental frequency but the sound lacks a component at the fundamental frequency itself.
  
  The brain perceives the pitch of a tone not only by its fundamental frequency, but also by the periodicity implied by the relationship between the higher harmonics; we may perceive the same pitch (perhaps with a different timbre) even if the fundamental frequency is missing from a tone.
   Each type of musical instrument has a characteristic sound quality that is largely independent of pitch or loudness. Some instruments have more than one timbre, e.g. the sound of a plucked violin is different from the sound of a bowed violin. Some instruments employ multiple manual or embouchure techniques to achieve the same pitch through a variety of timbres. If these timbres are essential to the melody or function, as in shakuhachi music, then pitch training alone will not be enough to fully recognize the music. Learning to identify and differentiate various timbres is an important musical skill that can be acquired and improved by training.
   If a performer has been trained using fixed do, particularly in those rare cases in which the performer has absolute pitch or well-developed long-term relative pitch, the performer may have difficulty playing music scored for transposing instruments: Because the "concert pitch" note to be performed differs from the note written in the sheet music, the performer may experience cognitive dissonance when having to read one note and play another. Especially in the early stages of learning a piece, when the performer has yet to gain familiarity with the melodic line of the piece as expressed in relative terms, he or she may have to mentally re-transpose the sheet music in order to restore the notes to concert pitch.
   Section::::Neurobiology.:Critical period.
  
  The development of the sensory modalities necessary for song learning occurs within a “critical period” of development that varies among avian vocal learners. Closed-ended learners such as the zebra finch and aphantochroa hummingbird can only learn during a limited time period and subsequently produce highly stereotyped or non-variable vocalizations consisting of a single, fixed song which they repeat their entire lives. In contrast, open-ended learners, including canaries and various parrot species, display significant plasticity and continue to learn new songs throughout the course of their lives.
   Section::::Gameplay.:Clef Climber.
  
  "Clef Climber" is a pitch-based video game where the player is given a reference note and then a tone corresponding to a different musical note that must be matched shortly after being played. As the game progresses, the reference note ceases to be played and the player must rely on his intuitive sense of pitch. The player can choose whether or not to view the notes on the musical staff, however even if musical notes are selected for display, they disappear at higher levels of the game.
  
  Section::::Reception.
   This finding led to another test that was designed to assess the presence of a deficiency in pitch perception. In this test, Monica heard a sequence of five piano tones of constant pitch followed by a comparison sequence of five piano tones in which the fourth tone could be the same pitch as the other notes in the sequence or a completely different pitch altogether. Monica was asked to respond "yes" if she detected a pitch change on the fourth tone or respond "no" if she could not detect a pitch change. Results show that Monica could barely detect a pitch change as large as two semitones (whole tone), or half steps. While this pitch-processing deficit is extremely severe, it does not seem to include speech intonation. This is because pitch variations in speech are very coarse compared with those used in music. In conclusion, Monica's learning disability arises from a basic problem in pitch discrimination, which is viewed as the origin of congenital amusia.
   Section::::Scientific studies.:Nature vs. nurture.
  
  Absolute pitch might be achievable by any human being during a critical period of auditory development, after which period cognitive strategies favor global and relational processing. Proponents of the critical-period theory agree that the presence of absolute pitch ability is dependent on learning, but there is disagreement about whether training causes absolute skills to occur or lack of training causes absolute perception to be overwhelmed and obliterated by relative perception of musical intervals.
   Trilby is tone-deaf: "Svengali would test her ear, as he called it, and strike the C in the middle and then the F just above, and ask which was higher; and she would declare they were both exactly the same."
   . Singers must also read and sing the correct lyrics, which adds another layer beyond pitch and dynamics. However, difficulty is related both to the instrument and the difficulty of the piece itself. For instance, sight-reading on a polyphonic instrument, such as the classical guitar, can be more challenging due to the fact that the guitarist has to read polyrhythms and polyphonic passages that can often be played in different positions using different frets.
  
  Section::::Terminology.
  
  Section::::Terminology.:Sight-reading.
   Studies on those with amusia suggest different processes are involved in speech tonality and musical tonality. Congenital amusics lack the ability to distinguish between pitches and so are for example unmoved by dissonance and playing the wrong key on a piano. They also cannot be taught to remember a melody or to recite a song; however, they are still capable of hearing the intonation of speech, for example, distinguishing between "You speak French" and "You speak French?" when spoken.
  
  Section::::Impairment.:Amygdala damage.
   The pitch of the missing fundamental, usually at the greatest common divisor of the frequencies present, is not, however, always perceived. Research conducted at Heidelberg University shows that, under narrow stimulus conditions with a small number of harmonics, the general population can be divided into those who perceive missing fundamentals, and those who primarily hear the overtones instead. This was done by asking subjects to judge the direction of motion (up or down) of two complexes in succession. The authors used structural MRI and MEG to show that the preference for missing fundamental hearing correlated with left-hemisphere lateralization of pitch perception, where the preference for spectral hearing correlated with right-hemisphere lateralization, and those who exhibited the latter preference tended to be musicians.
   Adults who possess relative pitch but do not already have absolute pitch can learn "pseudo-absolute pitch" and become able to identify notes in a way that superficially resembles absolute pitch. Certain people who train to name notes may indeed become able to identify all 12 notes of the scale with 90% accuracy or above, and Valproate, a medication used to treat epilepsy and severe depression, may re-open the "critical period" of learning, making the acquisition of absolute pitch, as well as languages, potentially as efficient for adults as for children.. Even so, pitch training can require considerable motivation, time, and effort, and learning is not retained without constant practice and reinforcement.
   Section::::Well temperament and equal temperament.
  
  Just intonation has the problem that it cannot modulate to a different key (a very common means of expression throughout the common practice period of music) without discarding many of the tones used in the previous key, thus for every key to which the musician wishes to modulate, the instrument must provide a few more strings, frets, or holes for him or her to use. When building an instrument, this can be very impractical.
   Unfretted string ensembles, which can adjust the tuning of all notes except for open strings, and vocal groups, who have no mechanical tuning limitations, sometimes use a tuning much closer to just intonation for acoustic reasons. Other instruments, such as some wind, keyboard, and fretted instruments, often only approximate equal temperament, where technical limitations prevent exact tunings. Some wind instruments that can easily and spontaneously bend their tone, most notably trombones, use tuning similar to string ensembles and vocal groups.
  
  Section::::History.
  