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Music Terms and Terminology

KNOWLEDGE BASE                      

Analog to Digital converter (ADC) Chords Digital Audio Tape (DAT)
Jam Band Midi Music Notation 
Pitch Rhythm Slide guitar
Synthesizer Tuning guitar by ear  
     
     
     
     
     
     

 First time Last time RECORD/MIXING

If YOU MUST HAVE IT the outcome is S n S out

1 You like a lot of bass! 2 You like the middle! 3 You like rhythm 4 You like highs 5 You like lows 6 You like it soft

7 You like it funky

And the list goes on. be my guest and even teacher if you can add just one more to the list.

Now that we got that over heres the outcome and why.

Mixing to a large degree is use common sense. Here's one ex. of how little common sense is needed to mix music or just about anything else you can mix. Lets make it simple! #1get a bowl (music bowl) #2 get some bass some guitar some drums some vocals get some or a lot of other instruments and throw them all in the bowl. (HINT#1) No one in their musically right or wrong mind would even think that if you say soup at this point then the outcome is the remainder of S n S out! Some gonna be loud some gonna be bland some gonna be some or a lot of other things than musically or tastefully right. #3 Put everyone in their place first. #4 Make sure they are playing what when and where of the song #5 Make sure they are not over loud S n S out (HINT#2) You simply say to the musician or digitally relay to you're equipment first about INDIVIDUAL/SOURCE volume in reference to input. Positively correct all volume/EQ/volume/mixing/volume/tonality/volume control at the INDIVIDUAL/SOURCE and not after the fact.S n S out #6 Now that all participants are in place and can be heard SET the input vol on your device that has inputs. #7 This device must be zeroed (0dB) (HINT#3) This means (0) across the board if it says input and can be EQ ed and you just have to move it for what ever reason make that move to (0)dB NOW IS THE TIME. If no well S n S out! Simply place each input slider on (0)dB that means using your hands okay . You wont like it but I assure you that it want hurt and the outcome pure what you need to get started so lets record/mix (HINT#4) If you tend to use reuse overly aggressive instruments or musicians; you must correct all signal out problems at INDIVIDUAL/SOURCE If INDIVIDUAL/SOURCE needs to hear the original signal its called headphone to monitor. That's pre the mixed signal ok before the board. One more time at the you got it now say it INDIVIDUAL/SOURCE (HINT#5)90 percent of all S n accures at this moment in mixing history. Remember you have the power to make it right and not let the S n get by you okay!!!!! 	Just think we have not even talked about the hard stuff yet right. Thought you would think that of this writing. You thinking right now what's up with this person? Surely you know everything that the person is talking about. Right Then why are you still reading. I know I know you just cant seem to do all that fantastic and boring mixing stuff. You're a musician you want to play. BUT!! You fill the buts as for me here is step #8 Okay not that we have the right input signal from the INDIVIDUAL/SOURCE Very little if any S n and all equipment is (0)dB push the button dude. Now you thought you really thought that there was gonna be so much more to this writing. Well if you think so then you are still letting a bunch of S n! Go ahead be my guest and even teacher if you can add just one more to the list. One thing is for sure if you follow just this one step use common sense all your record/mixes will be tight and this is the root to getting the master or demo recording. S n S out

Next writing master /demo recording/mixing

 

Digital Audio Tape (DAT)  Digital Audio Tape (DAT), magnetic tape cassettes used for sound recording and reproduction. Developed for professional use in the 1970 s and for the consumer market by the late 1980 s, digital recorders convert audio signals into digital data on a magnetic tape by means of a microprocessor (an analog-to-digital converter) and convert the data back into analog audio signals (by means of a digital-to-analog converter) for playback with the amplifier of a conventional stereo sound system. In digital recording, sound waves are sampled several thousand times per second and transformed into a series of pulses that correspond to patterns of binary numbers that are recorded on tape (or optical disk).Digital recorders/players appeared in the early 1980 s in the form of pulse code modulation (PCM) adapters for home videocassette decks. By 1983 the compact disk (CD) developed by the Sony Corporation (Japan) and Philips (the Netherlands), which used a laser beam to read optically  prerecorded digital information on the disk, had brought digital sound into the home market. Digital recordings provide higher fidelity sound reproduction—greater dynamic range and frequency response and less distortion—than conventional analog methods. The last obstacle to marketing digital audio tape for home use—the potential to make copies that are indistinguishable from original, copyrighted recordings—was overcome in the late 1980s. Manufacturers adopted the Serial Copy Management System (SCMS), which limits the ability to make digital copies of copies while allowing direct, first-generation digital copying of CDs and other digital sources (analog copying remains unlimited). By mid-1990, home users were able to make CD-quality recordings up to two hours long on durable and reusable cassettes about half the size of standard audio cassettes. "Digital Audio Tape (DAT)," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation.

Chord  Chord, in music, three or more tones sounded simultaneously. Chords are classified according to the interval between their tones. The most common kind of chord is the triad, which is built of two consecutive thirds: If the bottom interval is a major third and the top one a minor third, the chord is a major triad (as, C-E-G). If the intervals are in the order minor third-major third, the chord is a minor triad (as, C-E$-G or A-C-E). Less common are diminished triads (minor third plus minor third, as, C-E$-G$) and augmented triads (major third plus major third, as, C-E-G#). Triads can also be described as having the intervals of a third (such as C-E) and a fifth (C-G) formed with the root of the triad (here, C). When additional thirds are piled on top of a triad, sevenths, ninths, elevenths, and other chords result; the interval between the bottom and top tones of a seventh chord is a seventh, hence the name of the chord. The most common seventh chord, called a dominant-seventh chord, consists of a major triad plus a minor third (as, G-B-D-F); it is so termed because it is the form of the seventh chord built on the fifth, or dominant, scale-note of a given key. Seventh chords can also be built of other major-minor combinations. One combination is the diminished-seventh chord (a diminished triad plus a minor third, that is, three minor thirds: G-B$-D$-F$$). Jazz musicians often use major seventh chords such as G-B-D-F# (major triad plus major third). Chords have a strong aural identity, which they retain even when their tones are arranged in “inverted” order. Thus E-G-C (first inversion) and G-C-E (second inversion) are recognizable to the ear as versions of the C chord, C-E-G (normal or “root” position). Other intervals such as fourths and seconds can also be used to construct chords. Composers such as the Russian Aleksandr Scriabin, the German Paul Hindemith, and the Hungarian Béla Bartók explored quartal harmony, or the use of chords built of fourths. Tone-clusters, or chords built of consecutive seconds, were used by the American composers Henry Cowell and Charles Ives ."Chord," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation.

 Guitar Tuning by Ear   An Alternate Method For Tuning A guitar By Ear  1. Tune the high E to a pitch source (tuning fork, piano ect.) The thinking here is that it is more accurate to begin with a midrange source rather than a low source. 2.To tune the B string , play an E on the 5th fret of the B string. This is a unison so any beats (or no wavering) can be easily heard. Adjust the E on the B string according, so there are no beats. 3.To tune the D string, play an E on the 9th fret of the G string. Tune it to the open E string. As before, adjust the G string so there are no beats. 4. To tune the D string, play a B on the 9th fret of the D string. Tune it to the open B string 5. To tune the A string, play a G on the 10th fret of the A string. Tune it to the pen G string. 6. To tune the E string, play a D on the 10th fret of the low E string. Tune it to the open D string. At first, this might sound a little complicated but once you have done it once or twice, you'll get the idea. As stated before, this method is very useful for compensating for string or bridge inconsistencies. The tuning method most guitar and bass players begin with, tuning to unisons at the 5th fret on adjacent strings, is not accurate as it tunes to PERFECT 4ths rather than TEMPERED 4ths. This slight variation becomes accumulative as you work across the strings. the other common tuning method, tuning by harmonics at the 5th and 7th positions on adjacent strings, is equally flawed for the same reasons. Of cource, if we could learn (as piano tuner do) to know just how many beats per second there should be to tune to the non-pure equal temperment (which is universally used), then these methods could be used. Author Unknown:

Synthesizer  Synthesizer (computer), a computer peripheral, chip, or stand-alone system that generates sound from digital instructions rather than through manipulation of physical equipment or recorded sound. Most synthesizers can be attached to computers and sequencers using MIDI (Musical Instrument Digital Interface). Through MIDI, a computer can control multiple synthesizers, using the digital equivalent of sheet music and simulating the performance of a single musician or an entire orchestra. "Synthesizer (computer)," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation.

 Analog-To-Digital Converter, or ADC  Analog-To-Digital Converter, or ADC, an electronic device for converting data from analog to digital form for use in electronic equipment such as digital computers (see COMPUTER), digital audio and video recorders, and communication equipment. Analog or continuously varying electrical waveforms are applied to the device and are sampled at a fixed rate. Sample values are then expressed as a digital number, using a binary numbering system consisting only of 0's and 1's. The resulting digital codes can be used in various types of communications systems. "Analog-To-Digital Converter," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation.

Musical Rhythm Musical Rhythm, all aspects of music concerned with its motion through time and, thus, with its time structure. In addition to this overall meaning, the term rhythm is occasionally used to refer to specific time events, such as the patterns of lengths in a certain group of notes. In this article, individual technical terms are used for these more restricted meanings. Pulse and Meter Like the rhythms in nature, such as the motion of the planets, the succession of seasons, and the beating of the heart, musical rhythm usually is organized in regularly recurring patterns. Such patterns regulate the motion of the music and aid the human ear in grasping its structure. The most basic rhythmic unit is the beat or pulse—a recurring time pattern that resembles the ticking of a clock. In most popular and dance music, the pulse is explicitly stated, often by drumbeats or by a regular accompaniment pattern. In more complex music, the beat is often only implicit—a kind of common denominator for the actual lengths of the notes, which may be longer or shorter than the pulse itself. (When the listener taps a foot to such music, however, the pulse again becomes explicit.) For the pulse to be heard as a common denominator, the lengths of the individual notes must be its exact multiples or subdivisions (such as two short notes, each half as long as the pulse, or a note twice the length of the pulse). The tempo of the music determines the speed of the beat. In a fast tempo, the beat has a relatively short time value; in a slow tempo, the value of the beat is longer. Just as the beats regulate the durations of such short musical events as a note or a pair of notes, the beats themselves are regulated by larger recurring units called measures. Measures are formed by stressing the first in a series of two or more beats, so that the beats group themselves into a pattern, for example; ONE two, ONE two, or ONE two three, ONE two three. (The first beat is called the downbeat of the measure; the last beat is called the upbeat.) The term meter can refer, first, to this general process of regular accentuation, and second, to the particular metrical grouping used in a given piece. In musical notation, meter is indicated by the time signature. In the time signature h, for example, the lower number, 4, indicates that the basic pulse is written as a quarter-note; the upper number, 2, indicates that each measure has two quarter notes. Similarly, in u meter (or u time) each measure has six eighth-notes. In meters such as u, which are considered more complex and are known as compound meters, each measure has, in addition to the principal accent on the first beat, one or more subsidiary accents. Thus a u measure has a primary accent on the first beat and a secondary accent on the fourth beat: ONE two three, Four five six. Metrically organized music is highly structured and tends to be regular. Once the meter is established, however, it need not be rigidly adhered to at all times; the listener's mind will retain the pattern even if the music temporarily contradicts it. Thus, a normally weak beat can be stressed, producing a syncopation (an accent that works against the prevailing meter). Conversely, a strong beat may occasionally be suppressed completely. Indeed, in complex metrical music a degree of tension always exists between, on the one hand, the meter as an abstract system of regulation and, on the other hand, the rhythmic flow of the actual note lengths—a flow that at times supports the meter and at times does not. Furthermore, the pulse need not necessarily be maintained with absolute rigidity; it may be played rubato, that is, with variations so slight that they do not destroy the basic value. Larger Time Units Just as beats are grouped into measures, measures are themselves grouped into larger units. Such groupings produce the more extended segments of time that determine the form of the music. A motive (the shortest melodic idea that forms a relatively complete musical unit) may consist of more than one measure. One or more motives may be repeated and varied to form a phrase (a yet larger unit with a still more definite sense of ending, corresponding roughly to a sentence in language). Phrases are combined to produce sections, and sections are combined to produce entire compositions. Musical form is shaped by the relationships among these various time units and also by the relationship of these units to the whole; form in music is thus basically rhythmic in nature.

Western Use of Rhythm  From the Middle Ages to the present, Western music has consisted primarily of multipart music, in which two or more melodies are performed simultaneously, or else a melody is combined with accompaniment. This means that more than one note sounds at once. Moreover, the relationship of the simultaneous notes must conform to the requirements of Western music's highly developed system of harmony. These facts made necessary the development of a system of rhythm that could precisely regulate the various parts, allowing them to move independently, yet in strictly controlled coordination. The previously described metrical system, with its common underlying time-length framework, provided an ideal means for such coordination. Western music also required a notational system in which large numbers of mutually related time values could be indicated exactly (see MUSICAL NOTATION). The Western system of rhythm has thus been to some extent a matter of rational control and measurement. It has also made possible the creation of extended multipart compositions of great technical and dramatic complexity.

20th-Century Trends In the 20th century various composers tried to break away from what they considered the overly regular quality of metered music. One way was to alter the lengths of measures, creating a kind of variable meter. Thus, a series of four measures might have time signatures of m, p, i, and q. The only common denominator is the eighth-note of the pulse itself, which is added to produce a series of irregular larger groupings: 3 + 4 + 2 + 5. Another technique is polymeter, the simultaneous use of different meters in different parts. A more extreme approach, found in some music after about 1950, avoids meter entirely. Performers are allowed to fit a certain number of notes within a given time span (such as 10 seconds) at will, without following rules for exact coordination or measurement of the durations.

Non-Western Systems  In a sense, recent Western music seems to be coming closer to non-Western music, much of which is to some degree nonmetric, and in which improvisation is often important. Some musical cultures limit music to a single line of melody, with a small number of note lengths (in some cases, only two, one twice as long as the other). The note lengths, however, can be combined in various ways to create flexible, irregular larger patterns that are somewhat reminiscent of those found in Gregorian chant in early Western music. In India and Japan, in different ways, rhythm is highly systematized yet still preserves a degree of flexibility that transcends that of most Western music. In Indian music, for example, the durations are organized within a recurring time cycle known as a tala. Although tala has something in common with the Western measure, its patterns are usually considerably longer. Moreover, its subdivisions consist of units of unequal length that combine to form a freely flowing musical continuum within the tala. Other cultures have developed highly complex multipart music. African music, for instance, is largely improvised, the various parts being held together by a constant basic unit beaten out on a drum or by handclaps. The other parts are structured with great freedom relative to this unit, producing their own metrical patterns that only occasionally coincide with one another and with the basic pulse (see AFRICAN MUSIC AND DANCE). Although this system makes it impossible to produce the elaborate harmonic effects characteristic of metrical multipart music, it results in a rhythmic structure that is considerably more complex and varied. Contributed by: Robert P. Morgan  "Musical Rhythm," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation

MIDI  MIDI, acronym for Musical Instrument Digital Interface. In computer science, a serial interface standard that allows for the connection of music synthesizers, musical instruments, and computers. The MIDI standard is based partly on hardware and partly on a description of the way in which music and sound are encoded and communicated between MIDI devices. The hardware portion of the standard defines these types of input/output channels, called MIDI ports, and specifies a particular type of cable, a MIDI cable, that plugs into the ports. The three types of ports defined by the MIDI specification are MIDI In, MIDI Out, and MIDI Thru. A synthesizer or other MIDI device receives MIDI messages via its MIDI In port. It also echoes the messages back out through the MIDI Thru port so that other devices can receive them. MIDI devices send their own messages to other devices via the MIDI Out port. The information transmitted between MIDI devices is in a form called a MIDI message, which encodes aspects of sound such as pitch and volume as 8-bit bytes of digital information. MIDI devices can be used for creating, recording, and playing back music. Using MIDI, computers, synthesizers, and sequencers can communicate with each other, either keeping time or actually controlling the music created by other connected equipment. The standardization on MIDI by the major synthesizer manufacturers is partially responsible for the huge success of computers in the music profession. See also COMPUTER; SYNTHESIZER."MIDI," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation.

Musical Notation    Musical Notation, system of written symbols that represent musical sounds. The primary requirement of any notation is that it be suited to the music it represents.  Topics  1) History  2) Other notational systems

Western Staff Notation  The standard notation of Western music is a staff notation. Its basis is a staff (or stave) of five lines. Each line and the space between lines represents a different pitch. A tone of a given pitch is represented by a sign called a note, placed on a line or in a space. A clef, positioned at the beginning of every staff, indicates the pitch assigned to one of the lines, from which the others are reckoned. Since the octave contains 12 pitches a semitone (that is, a half-step) apart, and since the staff, for historical reasons, has lines and spaces only for seven pitches A, B, C, D, E, F, and G (five of which are a whole step from the following tone), three additional symbols are used. Placed next to a note, they alter its meaning, permitting the notation of the remaining pitches. They are the flat ($), which lowers the pitch of a note by a semitone; the sharp (#), which raises it by a semitone; and the natural (8), which cancels a previous flat or sharp. If certain flats or sharps appear regularly throughout a piece, their signs are placed next to the clef, in a key signature.The durations of notes are indicated by their specific shapes; the durations of silences are set forth by signs called rests. The terminology of notes and rests indicates their durational relationships: whole, half, quarter, eighth, sixteenth, thirty-second, sixty-fourth, each being double or half the value of its neighbor in the series. Meter, the grouping of musical beats into basic recurrent units, is also indicated. A time signature, which shows how the beats are to be grouped, is placed on the initial staff next to the key signature; and vertical lines (bar lines) mark off the metrical units, or measures. The time signature also indicates a system of stresses: The first beat of a metrical grouping is usually the strongest. Additional symbols indicate other aspects of the music.

What are some tunings for slide guitar?  Some slide guitarists use the standard tuning - EADGBE. It provides a minor triad on strings 1,2, & 3, as well as a major triad on strings 2, 3, and 4. It's good for playing rock. Most blues players use open tunings, such as open G: DGDGBD, and open D: DADF#AD. Both tunings can be raised up a step, to open A: EAEAC#E, and open E: EBEG#BE. Many of the great acoustic blues players used open tunings, such as Charley Patton, Robert Johnson, Son House, Blind Willie Johnson, and so many others, as well as electric slide masters from Elmore James to Bonnie Raitt. For more modern styles, any tuning can be used, and there are many alternate tunings you can explore. Here are a couple of slide tunings used by experimental music guitarist Ted Killian: CGDGBD (Ted raises this a half-step on electric guitar), and C#GDGBbD. Explore, and enjoy.Many thanks to Marty Piter, resident Musicians Friend tech support blues guitar guru, for his help with both this week's and last week's tips on slide guitar. Musician's Friend carries a wide selection of electric guitars, slides, and instructional materials for slide styles.

 History  Today's system developed over many centuries. The note shapes are derived from neumes, handwritten signs that were placed over the words of medieval chant. At first neumes gave only a vague indication of melodic directions and patterns. Gradually the shapes became more precise and, about AD 1000, staff lines were added: first one, then two, then four and five. By about 1200, the notation was reasonably exact as to pitch, but quite vague regarding duration. About that time the earliest durational notation appeared. Called modal notation, it specified a constantly repeated rhythmic mode, or pattern. About 1250 four durational note and rest shapes were established, as well as a set of rules for determining whether a given note should subdivide into two or three shorter notes. Additional symbols for smaller durations were soon added. Although this system measured duration, somewhat variably, it did not include metrical stress. Time signatures that regulated duration first appeared in 14th-century France. Each signature represented three levels of subdivision. Eventually one level was discarded. Most modern time signatures represent a basic unit plus one level of subdivision. With the introduction in the mid-15th century of white note heads (that is, unfilled outlines) in addition to the solid-color note heads already in use, the system was very close to modern notation. During the 17th and 18th centuries the final changes to modern key and metrical time signatures occurred. By the mid-18th century, subsidiary instructions as to tempo, articulation, performing techniques, and expressiveness were commonly added. The use of such symbols greatly accelerated in the 19th century. In the mid-20th century, critics pointed out that contemporary music was not well served by a system that was based on the seven unevenly spaced pitches of medieval music. The same criticism applied to rhythm subdivisions that were mostly duple and that treated tempo, dynamics, and articulation only vaguely.

Other Notational Systems  Alphabetical notations were used in ancient Greece and elsewhere. Jazz charts may indicate only the harmonic structure, leaving all the rest to the performer. In addition to their western uses, neumes have also been employed in China, Japan, and the Near East as well as for Tibetan chant. Tablatures are compact notations that use signs, numbers, or letters, usually to notate fingerings rather than pitches. Modern popular guitar tablature is a small grid in which vertical lines represent the strings and horizontal lines represent the frets; black dots indicate where to put the fingers. Writers discussing music sometimes use the following system to specify pitches: CC-BB = third C through third B below middle C; C-B = second C through second B below middle C (that is, C = C below the bass staff); c-b = C through B below middle C; c1-b1 = middle C through the B above it; c2-b2 = C above middle C through the B above that; c3-b3 = second C above middle C through the B above that (that is, c3 = C above the treble staff). In the 20th century, composers of “indeterminant” compositions leave many elements deliberately vague and to chance; this is also true of their unconventional notation. Contributed by: Walter Gerboth "Musical Notation," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation.

Synthesizer Synthesizer (computer), a computer peripheral, chip, or stand-alone system that generates sound from digital instructions rather than through manipulation of physical equipment or recorded sound. Most synthesizers can be attached to computers and sequencers using MIDI (Musical Instrument Digital Interface). Through MIDI, a computer can control multiple synthesizers, using the digital equivalent of sheet music and simulating the performance of a single musician or an entire orchestra. "Synthesizer (computer)," Microsoft (R) Encarta. Copyright (c) 1994 Microsoft Corporation. Copyright (c) 1994 Funk & Wagnall's Corporation.

Jam Band / Song Band not the same! Remember your first shot at becoming a member of a newly formed or local band! Remember that after all the practice and learning finally, the chance to strut your musical accomplishments were now a reality. You had done the work and was ready to reap the benefits of being so musically inclined. Hopefully upon your induction into said band, rehearsals were more about learning to play the tunes and not learn your AXE jam sessions! I have taken part in jam sessions where good bands have started. I have also taken part in bands where rehearsals were sweat get wet burn me out jam sessions! Leave feeling whipped and noncommitted. People would come up to me and say " Hey , heard you were in a band! You know we are having a party and... and that's when I would start to back off. Yeah! I'd say but did you know I'm in a JAM BAND its the band that knows no songs just long sessions of JAMMING. You know when you play the longest ever played song. It is within these sessions musicians can loose there perspective on getting out there and playing. Strive to build that song list. Include well known tunes and by all means include a few cover tunes. I recently talked to a friend who had auditioned for a supposedly working group and found out at the first rehearsal that his song list was much greater than the working band. Rehearsal was no more than a well planned jam session. When ever I hold a jam session or attend one I make sure that they are learning sessions as well as jamming. Those who participate as well as myself leave with more than we came in with. The learning process continues. So learn the tunes and keep on Enjoying the music 

HOW DOES MIDI MAKE MUSIC?  If MIDI was just another way of sending information from one computer-based device to another, you wouldn't be reading about it in Keyboard. What makes MIDI special is that the information that travels along a MIDI cable relates specifically to music performance. To begin with, MIDI defines note-on and note-off messages. When you press a key on a MIDI keyboard, the keyboard transmits a note-on message. This tells any MIDI device that happens to be listening that a new note has begun. When you lift the key, the keyboard sends a note-off message. This tells any receiving device that it's time to stop playing that particular note. One of the most basic concepts in MIDI is this: The note-on message says nothing about the actual sound of the note. It only says, "Start a note now." The sound depends entirely on the receiving module. If it's set up to make a piano-type sound, the note-on message will cause a piano note to sound. If the receiving module is set to play saxophone, the exact same note-on message will generate a sax note. A single note-on message has three parts. The first part, called the status byte, defines what type of message it is - in this case, that it's a note-on message, and that it is on, let's say, MIDI channel 3. (For more on channels, see below.) The second part of the note-on message is the note number. In other words, which key is being played? In theory, a MIDI keyboard can be 128 notes wide, because 128 note numbers are available. A typical five-octave MIDI keyboard uses the notes between 36 and 96. (Middle C is note 60.) The third part of the note-on message is the velocity. This number, which can be anywhere from 1 to 127, tells how fast the key was travelling as it moved from its starting position down toward the keybed. Normally, a synthesizer will respond to a higher velocity by making the note louder or brighter. A note-off message has the same three parts - the status byte, the note number, and the velocity. The note-off velocity (which is more often called release velocity) can be different than the note-on velocity. But only a few MIDI keyboards can sense the velocity with which a key rises from the keybed, and only a few MIDI synths can alter their sound based on the release velocity value that they receive. Most MIDI keyboards transmit a fixed release velocity of 64, no matter how quickly or slowly you lift the key. By the way, a MIDI note-on message with a velocity of zero works the same as a note-off message. It turns the note off rather than turning it on. This message is used for technical reasons that we aren't going to try to explain here. For the most part, you shouldn't need to worry about it. All that matters in most musical situations is the obvious: When you press a key, a note starts. When you lift the key, the note stops. MIDI defines a number of other musically useful performance messages. Some are used quite a lot, and some more rarely. Here are the types you'll run into most often: Pitch-bend messages are usually transmitted by the pitch wheel, lever, or joystick. The message itself says nothing about the actual depth of the pitch-bend as a musical interval. The receiving synth might be set to bend up and down by a maximum of an octave, a major second, or by some other interval. The pitch-bend message contains information only about the position of the wheel or equivalent hardware. If the wheel is moved halfway from its center position to the top of its travel, the pitch will move halfway from the starting pitch of the note to the maximum bend interval. Program change messages are usually transmitted by pressing the program change buttons on the front panel of the synth. They tell the receiving module to switch to a new program (also called a patch, sound, voice, or preset) within its stored memory bank. But again, what exactly the program will sound like is not determined by the MIDI message. A MIDI program change message is in two parts. The status byte says, "Program change, channel XX" (that is, some channel number between 1 and 16), and the second byte, which is called a data byte, gives a program number between 1 and 128. The receiving module will switch to whatever program it happens to have stored in the memory location that corresponds to that number. The new General MIDI specification changes this picture a bit. Modules that are General MIDI compatible will have specific types of programs stored in specific numbered memory locations. This allows you to call up, say, program 17 and have some confidence that it will do the job musically, because program 17 will always be a drawbar organ sound on any General MIDI synth. But the basic principle is still true. The transmitting synth has no idea whether the receiving synth is a General MIDI instrument or not. There is no such thing as a "General MIDI program change" that exists as a separate type of MIDI message. The program change message is always the same, but if the receiving synth is one you haven't worked with before, sending program changes will give you more musically predictable results if it's General MIDI compatible than if it's not.As with most of the messages we're looking at, there are wrinkles in the area of program changes that we're not going to try to deal with this month - things like, what happens if a synth only stores 64 programs in its memory, and you send it program change 103? It might ignore the program change, it might switch to program 39 (because 103 - 64 = 39), or it might do something else. Pressure messages are used to alter the sound of notes while the notes are sustaining. Pressure comes in two flavors. Channel pressure messages have an identical effect on all of the notes that are sustaining, while the key pressure (also called polyphonic pressure) value can be different for each note in a chord. Pressure is also called aftertouch. Continuous controller messages make other kinds of changes in sustaining notes. MIDI has room for more than 100 continuous controllers to operate on each channel, but very few synths can respond to this many at any given time. The continuous controllers are numbered. Some of the numbers have well-defined meanings, while others are left undefined so that each instrument can use them in its own musical ways. The most commonly used continuous controllers are controller 1, which is the modulation wheel, controller 64, which is the sustain pedal, and controller 7, which controls the overall volume of an instrument. These messages are all called channel messages. If you read last month's column, you'll remember that MIDI defines 16 channels. All of the notes, pitch-bends, program changes, and other messages we've been talking about are tagged with a channel number between 1 and 16. If the tone module on the other end of the cable is set up to receive on the same channel that the message is on, then it will respond by doing whatever the message tells it to - assuming that it's also capable of responding to that type of message. Many modules ignore polyphonic aftertouch, for instance. If the message is on the wrong channel - a channel that the module is not set up to respond to - the message will also be ignored. One other big issue that we should at least mention is timing. In order to be musically usable, MIDI has to be able to transmit note-ons, note-offs, and other messages very quickly. (If you played a note and heard it half a second later, you wouldn't like it.) Without going into a lot of technical detail, we can say that as a rule of thumb, a MIDI note-on requires about 1 millisecond (that's one thousandth of a second) to be transmitted. And MIDI messages are sent down the cable one at a time. So if you want to transmit a 20-note chord over MIDI, it takes about 20 milliseconds (1/50 of a second). If you think of a chord as a group of notes that all start at exactly the same moment, then MIDI can't transmit chords at all. Those 20 notes are sent one after another, as a very, very fast arpeggio. We'll have much more to say about timing in another column. For now, what's most important to understand is this: It's possible to clog up the MIDI data stream with so many pressure and continuous controller messages that the timing of the notes gets pushed around, resulting in a loose, sloppy-sounding performance. But this doesn't happen as often as you might expect. Most of the timing problems that you'll hear with MIDI instruments are due to the receiving synth responding too slowly Ñ for example, taking 20 or 30 milliseconds after the MIDI message has arrived to switch on a single note. You won't hear nearly as much time slop with newer instruments as with older ones. If you've only got two hands, there's a limit to how much you can do with MIDI in a live performance. We'll cover that another time, when we ask, What is a sequencer?