Signal Processing Projects using Matlab for ECE Students. List of Best MATLAB Signal Processing Projects Titles and Ideas for Engineering students which includes Audio Signal Processing, Biomedical Signal Processing & Digital Signal Processing Matlab Mini Projects with Free Source Code Download. The aim of this master´s thesis is to. This project is meant to develop a device that can accurately detect breathing through sound and issue appropriate warnings upon its cessation. The device produced is meant to be a standalone device and thus was developed as an embedded systems project on a Xilinx Spartan 6 FPGA. Talk to Expert Submit Assignment. Project Glock - Simple Glockenspiel Price: $9.95: Project One - Box Resonated Xylophone Price: $27: Project Two - Two Octave Mini Marimba Price: $39.95: Project Three - Three Octave Concert Marimba Price: $49.95: Project 524 - Variable range Professional Concert Marimba (5 Octave model shown) Price: $73: Project V - Concert Vibraphone Price: $64.95.

A musical keyboard is the set of adjacent depressible levers or keys on a musical instrument. Keyboards typically contain keys for playing the twelve notes of the Western musical scale, with a combination of larger, longer keys and smaller, shorter keys that repeats at the interval of an octave. Depressing a key on the keyboard makes the instrument produce sounds—either by mechanically striking a string or tine (acoustic and electric piano, clavichord), plucking a string (harpsichord), causing air to flow through a pipe organ, striking a bell (carillon), or, on electric and electronic keyboards, completing a circuit (Hammond organ, digital piano, synthesizer). Since the most commonly encountered keyboard instrument is the piano, the keyboard layout is often referred to as the piano keyboard.

Description[edit]

The twelve notes of the Western musical scale are laid out with the lowest note on the left;^[1] The longer keys (for the seven 'natural' notes of the C majorscale: C, D, E, F, G, A, B) jut forward. Because these keys were traditionally covered in ivory they are often called the white notes or white keys. The keys for the remaining five notes—which are not part of the C major scale—(i.e., C♯/D♭, D♯/E♭, F♯/G♭, G♯/A♭, A♯/B♭) (see Sharp and Flat) are raised and shorter. Because these keys receive less wear, they are often made of black colored wood and called the black notes or black keys. The pattern repeats at the interval of an octave.

The arrangement of longer keys for C major with intervening, shorter keys for the intermediate semitones dates to the 15th century. Many keyboard instruments dating from before the nineteenth century, such as harpsichords and pipe organs, have a keyboard with the colours of the keys reversed: the white notes are made of ebony and the black notes are covered with softer white bone. A few electric and electronic instruments from the 1960s and subsequent decades have also done this; Vox's electronic organs of the 1960s, Farfisa's FAST portable organs, Hohner's Clavinet L, one version of Korg's Poly-800 synthesizer and Roland's digital harpsichords.

Some 1960s electronic organs used reverse colors or gray sharps or naturals to indicate the lower part (or parts) of a single keyboard divided into two parts, each controlling a different registration or sound. Such keyboards accommodate melody and contrasting accompaniment without the expense of a second manual, and were a regular feature in Spanish and some English organs of the renaissance and baroque eras. The break was between middle C and C-sharp, or outside of Iberia between B and C. Broken keyboards reappeared in 1842 with the harmonium, the split occurring at E4/F4.

The reverse-colored keys on Hammond organs such as the B3, C3 and A100 are latch-style radio buttons for selecting pre-set sounds.

Size and historical variation[edit]

The chromatic range (also called compass) of keyboard instruments has tended to increase. Harpsichords often extended over five octaves (>60 keys) in the 18th century, while most pianos manufactured since about 1870 have 88 keys. The lowest pitch (frequency: 27.5 Hz) of an 88-key piano is equivalent to a sub contrabass in the range name. Some modern pianos have even more notes (a Bösendorfer 290 'Imperial' has 97 keys, and a Stuart & Sons model has 108 keys^[2]). While modern synthesizer keyboards commonly have either 61, 76 or 88 keys, small MIDI controllers are available with 25 keys. (Digital systems allow shifting octaves, pitch, and 'splitting' ranges dynamically, which, in some cases, reduce the need for dedicated keys. However, smaller keyboards will typically limit which musical scores can be played.) Organs normally have 61 keys per manual, though some spinet models have 44 or 49. An organ pedalboard is a keyboard with long pedals played by the organist's feet. Pedalboards vary in size from 12 to 32 notes.

In a typical keyboard layout, black note keys have uniform width, and white note keys have uniform width and uniform spacing at the front of the keyboard. In the larger gaps between the black keys, the width of the natural notes C, D and E differ slightly from the width of keys F, G, A and B. This allows close to uniform spacing of 12 keys per octave while maintaining uniformity of seven 'natural' keys per octave.

Over the last three hundred years, the octave span distance found on historical keyboard instruments (organs, virginals, clavichords, harpsichords, and pianos) has ranged from as little as 125 mm (4.9 in) to as much as 170 mm (6.7 in). Modern piano keyboards ordinarily have an octave span of 164–165 mm (6.5–6.5 in), resulting in the width of black keys averaging 13.7 mm (0.54 in) and white keys about 23.5 mm (0.93 in) at the base, disregarding space between keys. Several reduced-size standards have been proposed and marketed. A 15/16 size (152 mm (6.0 in) octave span) and the 7/8 DS Standard (140 mm (5.5 in) octave span) keyboard developed by Christopher Donison in the 1970s and developed and marketed by Steinbuhler & Company. U.S. pianist Hannah Reimann has promoted piano keyboards with narrower octave spans and has a U.S. patent on the apparatus and methods for modifying existing pianos to provide interchangeable keyboards of different sizes.^[3]

There have been variations in the design of the keyboard to address technical and musical issues. The earliest designs of keyboards were based heavily on the notes used in Gregorian chant (the seven diatonic notes plus B-flat) and as such would often include B♭ and B♮ both as diatonic 'white notes', with the B♮ at the leftmost side of the keyboard and the B♭ at the rightmost. Thus, an octave would have eight 'white keys' and only four 'black keys'. The emphasis on these eight notes would continue for a few centuries after the 'seven and five' system was adopted, in the form of the short octave: the eight aforementioned notes were arranged at the leftmost side of the keyboard, compressed in the keys between E and C (at the time, accidentals that low were very uncommon and thus not needed). During the sixteenth century, when instruments were often tuned in meantone temperament, some harpsichords were constructed with the G♯ and E♭ keys split into two. One portion of the G♯ key operated a string tuned to G♯ and the other operated a string tuned to A♭, similarly one portion of the E♭ key operated a string tuned to E♭, the other portion operating a string tuned to D♯. This type of keyboard layout, known as the enharmonic keyboard, extended the flexibility of the harpsichord, enabling composers to write keyboard music calling for harmonies containing the so-called wolf fifth (G-sharp to E-flat), but without producing aural discomfort in the listeners (see Split sharp). The 'broken octave', a variation of the aforementioned short octave, similarly used split keys to add accidentals left out of the short octave. Other examples of variations in keyboard design include the Jankó keyboard and the chromatic keyboard systems on the chromatic button accordion and bandoneón.

Electronic keyboards[edit]

Simpler electronic keyboards have switches under each key. Depressing a key connects a circuit, which triggers tone generation. Most keyboards use a keyboard matrix circuit, in which 8 rows and 8 columns of wires cross — thus, 16 wires can provide 8 × 8 = 64 crossings, which the keyboard controller scans to determine which key was pressed.^[4] The problem with this system is that it provides only a crude binary on/off signal for each key. Better electronic keyboards employ two sets of slightly offset switches for each key. By determining the timing between the activation of the first and second switches, the velocity of a key press can be determined, greatly improving the performance dynamic of a keyboard. The best electronic keyboards have dedicated circuits for each key, providing polyphonic aftertouch.

Advanced electronic keyboards may provide hundreds of key touch levels^[5] and have 88 keys, as most pianos do.

Playing techniques[edit]

Despite their visual similarity, different keyboard instrument types require different techniques. The piano hammer mechanism produces a louder note the faster the key is pressed, while the harpsichord's plectrum mechanism does not perceptibly vary the volume of the note with different touch on the keyboard. The pipe organ's volume and timbre are controlled by the flow of air from the bellows and the stops preselected by the player. Players of these instruments therefore use different techniques to color the sound. An arranger keyboard may be preset to produce any of a range of voices as well as percussion and other accompaniments that respond to chords played by the left hand.

Even though the keyboard layout is simple and all notes are easily accessible, playing requires skill. A proficient player has undertaken much training to play accurately and in tempo. Beginners seldom produce a passable rendition of even a simple piece due to lack of technique. The sequences of movements of the player's hands can be very complicated. Problems include wide-spanned chords, which can be difficult for people with small hands, chords requiring unusual hand positions that can initially be uncomfortable, and fast scales, trills and arpeggios.

Playing instruments with velocity sensitive (or dynamic) keyboards (i.e., that respond to varying playing velocity) may require finger independence, so that some fingers play 'harder' while others play more softly. Pianists call this control of touch velocity voicing (not to be confused with a piano technician's 'voicing' of a piano by modifying the hardness of the hammers). Keyboardists speak of playing harder and softer, or with more or less force. This may accurately describe the player's experience—but in the mechanics of the keyboard, velocity controls musical dynamics. The faster the player depresses the key, the louder the note. Players must learn to coordinate two hands and use them independently. Most music is written for two hands; typically the right hand plays the melody in the treble range, while the left plays an accompaniment of bass notes and chords in the bass range. Examples of music written for the left hand alone include several of Leopold Godowsky's 53 Studies on Chopin's Etudes, Maurice Ravel's Piano Concerto for the Left Hand and Sergei Prokofiev's Piano Concerto No. 4 for the left hand. In music that uses counterpoint technique, both hands play different melodies at the same time.

Other uses[edit]

A number of percussion instruments—such as the xylophone, marimba, vibraphone, or glockenspiel— have pitched elements arranged in the keyboard layout. Rather than depress a key, the performer typically strikes each element (bell, metal or wood bar, etc.) with a mallet.

There are some examples of a musical keyboard layout used for non-musical devices. For example, some of the earliest printing telegraph machines used a layout similar to a piano keyboard.^[6][7]

Keyboards with alternative sets of keys[edit]

There are some rare variations of keyboards with more or fewer than 12 keys per octave, mostly used in microtonal music, after the discoveries and theoretical developments of musician and inventor Julián Carrillo (1875–1965).

Some free-reed instrument keyboards such as accordions and Indian harmoniums include microtones. Electronic music pioneer Pauline Oliveros played one of these. Egyptian belly-dance musicians like Hassam Ramzy use custom-tuned accordions so they can play traditional scales. The small Garmon accordion played in the Music of Azerbaijan sometimes has keys that can play microtones when a 'shift' key is pressed.

See also[edit]

• Archicembalo, instrument with alternate keyboard with 36 keys
• Fokker organ, 31TET tuned organ with alternate keyboard

References[edit]

1. ^An exception is the hurdy-gurdy, whose crank is turned with the left hand.
2. ^King, Rosie (September 14, 2018). 'World's first 108-key concert grand piano built by Australia's only piano maker'. ABC. Retrieved 2018-09-15.
3. ^Reimann, Hannah. Patent claim #6,020,549, August 10, 1998.
4. ^Dave Dribin. 'Keyboard Matrix Help', (June 24, 2000).
5. ^Digital piano specs (100 pressure levels specified).
6. ^George M. Phelps, U.S. Patent 0,026,003Improvement in Telegraphic Machines issued November 1, 1859
7. ^The House Printing Telegraph (image)

• Bond, Ann (1997). A Guide to the Harpsichord. Amadeus Press. ISBN1-57467-063-8.

External links[edit]

Wikimedia Commons has media related to Musical keyboards.

Wikisource has the text of the 1911 Encyclopædia Britannica article Keyboard .

• 3D/2D Virtual piano, Online piano with examples of chords, scales, progressions and songs, with recording features.
• KeyLess Online, Western notes & Carnatic swaras laid out on the keyboard
• Virtual Piano Keyboard Online, Free to use
• A Piano Keyboard Layout by Piano Play It, a full layout of the piano keyboard with a piano tutorial
• Keyboard Magazine, selections from magazine, along with multimedia examples
• Electronic Keyboard News, news and reviews of keyboards, synthesizers and synth modules
• Keyboard Chords, chords for keyboards
• MathPages, mathematical discussion of the distribution of the keys
• Balanced Keyboard, A modified symmetrical layout of the standard keyboard. The website shows how to build your own.

Got Questions? Want to speak to me LIVE? Contact me right now with Start Chat or Voice Call

Dear Parent, Music Educator or Percussion Enthusiast,

Have you ever wished that you could get something bigger than a small “table top” style xylophone, yet not a full size concert xylophone or marimba?

• Maybe your child is studying tuned percussion and needs a serious instrument at home that won't fill the whole room, and won't break the bank...

• Maybe you need instruments for the classroom that are not considered toys by the students, but are still small enough to have one for each student...

You have probably discovered that there just are not instruments that fill this gap - something bigger and more serious than the small “orff style” classroom xylophones but not as big as a concert instrument.

... of course there are a few “Bass Xylophones” with large box resonators - but the last time I checked they cost almost $1000! And they still sit on the floor and don’t have individually resonated notes.

Sit down on carpet = children’s instrument
Stand up to play = musician’s instrument

Don’t get me wrong - there is nothing wrong with the small “box resonated” xylophones - such as available in my project one building plans.

...because for primary and elementary school classrooms these are ideal - the music class sits on the carpet and plays simple tunes, usually with one mallet only.

But older students expect much more these days! Imagine getting senior students to sit on the carpet and play small box xylophones - they just don't take them seriously, and you could actually be turning them away from music!

However... tuned percussion is a great learning tool for music fundamentals at any age because:

• You don’t have to worry about sound production (unlike wind and string instruments which are difficult to even get a sound from at the beginning)

• They are so inexpensive you can even have a whole bunch of em'!

• It's Visual! - You can actually see the musical scales you are playing.

Play standing up OR Sitting down!
Packs away easily.

and the P2 Mini-Marimba has some cool design features...

ONE: It dismantles in just 2 easy steps.

You see how simple the construction of the leg parts are? They just slot in to the main frame part. That was done on purpose so you can....

TWO:Easily and cheaply make an additional pair of shorter legs for sit-down playing.

Choosing a practice instrument for beginner percussion students

Box resonated simple xylophones have never been suitable for the serious percussion student, and certainly not to practice at home. Most beginning percussion students if they want to learn tuned percussion have been forced to start on glockenspiel (orchestral bells), and then get a concert xylophone or marimba if and when they can afford one.

And if you've ever listened to a beginner percussionist practicing on the bells... you very quickly realise that bells can be extremely loud and piercing due to the small metal bars that they are made from. Don't get me wrong - these instruments do have their place. In fact I've even designed and built them myself and the plans are available here.

Finally though... there is another,.. way better option - A small wooden marimba that can be made at home from commonly available materials!

box resonated VS individually resonated notes

OK - What is a resonator… and why does it matter?

Mini Projects For Cse

The sound on a xylophone or marimba is made by the wooden bar that is hit.

...so when you hit the bar, the air immediately around it vibrates...

... and if you capture that air in a container of the right size - you’ll make the sound louder

You see, that is what a resonator essentially does - it captures the vibrations that come from the note that has just been hit and it makes them louder.

A Box Resonator

So the boxes used by small Orff style xylophones are carefully designed to get the correct amount of air vibrating. If you look inside the box of any small xylophone you’ll sometimes see what looks like complicated bits of wood making it smaller in places and larger in other places.

... and the reason is that each note needs a different amount of air in the box to amplify the sound correctly...

BUT... if you listen carefully to a box resonated xylophone you’ll find that no matter what brand it is, how expensive or carefully made it is, some notes will “sing” more clearly than others - this is just because a box resonator cannot possibly be exact in its attempt to be the correct size for each note.

Individual Tube Resonators

In CONCERT xylophones and marimbas you’ll find each note has a tube underneath, which is precisely tuned to the exact note. This gives your P2 mini-marimba a much more even and pure sound as well as maximizing the volume from each note and the accuracy of its pitch.

Octave Mini Projects -

So... for the elementary or primary school classroom box resonated instruments are fine, but I firmly believe that for older school students or if you are actually learning tuned percussion, an individually resonated instrument is the way to go.

Octave Mini Projects Download