240 likes | 376 Views
MUSIC 318 PLUCKED STRING INSTRUMENTS. HARPS. HISTORY. THE EARLIEST HARPS APPEARED IN MESOPOTAMIA IN THE THIRD MILLENIUM BCE. THEY WERE OF THE ARCHED VARIETY, HAVING AN OPEN L-SHAPE FRAME WITH THE STRINGS JOINING THE TWO PARTS. IN EGYPT, SOME OF THE EARLIEST IMAGES OF BOW
E N D
MUSIC 318 PLUCKED STRING INSTRUMENTS HARPS
HISTORY THE EARLIEST HARPS APPEARED IN MESOPOTAMIA IN THE THIRD MILLENIUM BCE. THEY WERE OF THE ARCHED VARIETY, HAVING AN OPEN L-SHAPE FRAME WITH THE STRINGS JOINING THE TWO PARTS. IN EGYPT, SOME OF THE EARLIEST IMAGES OF BOW HARPS ARE FROM THE PHARAOH’S TOMBS DATING SOME 5000 YEARS AGO. THESE HIEROGLYPHS SHOW THAT THERE WERE MANY HARPS IN ANCIENT EGYPT. THE EGYPTIAN PARAOH RAMSES III (1198-1166 BC) HAD MANY BOW HARPS PAINTED IN HIS TOMB. IN THE NEW KINGDOM, HARPS MEASURED UP TO 2 m IN HEIGHT WITH 19 STRINGS AND WERE PLAYED SEATED OR STANDING UP
EARLY HARPS The word "harpa" or "harp" comes from Anglo-Saxon, Old German, and Old Norse words meaning "to pluck". By the 13th century the term was being applied specifically to the triangular harp as opposed to the lyre harp. The earliest Gaelic term for a wire-strung instrument was "cruit" was applied specifically to the harp by 1200. A later word used in Scotland and Ireland for the "Celtic" harp was clarsach or cláirseach. Scottish records of the 15th and 16th centuries show that both the terms "harp" and "clarsach" were in use at the same time, and seem to indicate that there was a distinction between the gut-strung European-style harps and wire-strung Gaelic clarsachs.
MODERN CONCERT HARP THE MODERN CONCERT HARP HAS 46 or 47 STRINGS RUNNING from C1 or D1 to G7. THE STRINGS RUN FROM THE CENTER OF THE SOUNDBOARD TO THE LEFT SIDE OF THE NECK. AT THE TOP THEY ARE WRAPPED AROUND A TUNING PEG, USED FOR TUNING, AND A BRIDGE PIN. BENEATH THE BRIDGE PIN ARE THE TUNING DISCS WHICH RAISE THE PITCH ONE OR TWO SEMITONES. THE STRINGS ARE TUNED A SEMITONE FLAT; THE FIRST DISC RAISES THE STRING TO NATURAL; THE SECOND TO SHARP. THE SHARPING MECHANISMS ARE CONTROLLED FROM 7 PEDALS. THE MECHANISM IS QUITE COMPLEX AND RUNS UP THE FOREPILLAR OR POST INTO THE NECK.
DIATONIC vs CHROMATIC STRINGING CHROMATIC MUSIC HAS ALWAYS BEEN A CHALLENGE FOR HARP MAKERS AND PLAYERS. THE STRINGS HAVE TO BE A FINGER-WIDTH APART AND REACHABLE WITHIN AN ARM LENGTH. MODERN CONCERT HARPS HAVE STRINGS ARRANGED DIATONICALLY WITH PROVISION FOR SHARPING OR FLATTING NOTES WHEN NECESSARY.
BUILDING A HARP DESIGNING AND BUILDING A HARP PRESENTS SEVERAL TECHNICAL CHALLENGES. A LARGE NUMBER OF STRINGS ARE NEEDED TO OBTAIN A USEABLE PITCH RANGE, AND THIS INEVITABLY PUTS THE SOUNDBOARD UNDER GREAT STRESS. SECONDLY THE HARP TENDS TO BE A QUIET INSTRUMENT AND NEEDS A VERY THIN SOUNDBOARD , WHICH PRESENTS PROBLEMS IN ANCHORING THE STRINGS. A MODERN CONCERT HARP IS MADE STRONG ENOUGH TO WITHSTAND A TOTAL STRING TENSION OF ABOUT 12-20 kN. THE SOUNDBOARD IS APPROXIMATELY TRAPEZOIDAL IN SHAPE, AROUND 1.4 m IN LENGTH, 0.5 m AT THE BASE END TO 2 mm AT THE TREBLE END. IT IS MADE OF STRIPS OF SPRUCE 7 OR 8 cm WIDE BONDED TOGETHER, GRAIN RUNNING TRANSVERSELY AND COVERED IN A THIN VENEER WITH LONGITUDINAL GRAIN. THE STRINGS ARE CONNECTED THROUGH TWO STRONG RIBS OR BARS OF HARDWOOD, ONE ON EACH SIDE OF THE SOUNDBOARD, MOUNTED CENTRALLY, THE COVER BAR VISIBLE ON THE FRONT AND THE HEAVIER REINFORCING BAR INSIDE. IN ADDITION, HARMONIC BARS ARE MOUNTED APPROXIMATELY LONGITUDINALLY ON THE BACK OF THE SOUNDBOARD.
VIBRATIONAL MODES OF SOUNDBOARD TUNING MECHANISM
STRING TENSION SALVI AURORA 47-STRING CONCERT HARP
SOUNDBOX THE EARLIEST HARPS WERE CARVED FROM SOLID WOOD. IN THE 17TH CENTURY, HARPS WERE CONSTRUCTED OF THINNER WOOD PARTS GLUED TOGETHER AND BRACED. THE MODERN SOUNBOARD CONSISTS OF A DOZEN OR MORE PIECES, GLUED EDGE TO EDGE WITH A THIN VENEER OF SPRUCE BONDED ON TOP OF THE SOUNDBOARD. THE HELMHOLTZ RESONANCE OF A TYPICAL SOUNDBOX IS FOUND TO BE ABOUT 190 Hz.
MODE FREQUENCIES, DAMPING COEFFICIENTS, AND MODE SHAPES FOR A CAMAC ATLANTIDE HARP
SOUND SPECTRA SOUND SPECTRA FOR THE F3 AND F4 STRINGS OF A SALVI AURORA HARP PLUCKED AT THE CENTER
SOUND RADIATION ENVELOPE OF SOUND RADIATION FOR THE F4 STRING OF A SALVI AURORA HARP PLUCKED AT THE CENTER. 14 Hz BEATING BETWEEN THE STRING (349 Hz) AND A NEARBY SOUNDBOARD RESONANCE AT 335 Hz CAN BE SEEN
ACOUSTIC INTENSITY • Sound intensity is the flow of acoustic power through a surface • A sound intensity probe has two accurately-spaced microphones to measure pressure and pressure gradient • Active intensity denotes energy flow to the far field • Reactive intensity denotes energy stored in the near field
SOUND RADIATION FIELD FROM A HARP AT LOW FREQUENCY RADIATION FROM A CAMACS CONCERT HARP WAS FOUND TO BE MOSTLY FROM THE BOTTOM PART OF THE SOUNDBOARD AND THE FIRST TWO SOUND HOLES. IN THE FREQUENCY RANGE 100-220 Hz THE SOUND INTENSITY FIELD CAN BE APPROXIMATED BY A SUPERPOSTION OF TWO POINT SOURCES . FROM 220-400 Hz RADIATION FROM THE TOP SURFACE OF THE SOUNDBOARD EXCEEDS THE RADIATION FROM THE SOUND HOLES, BUT FROM 400-470 Hz THE SOUNDHOLE RADIATION AGAIN PREDOMINATES. THE SAME IS TRUE FROM 490-550 Hz. RADIATION FROM THE SOUNDBOARD PREDOMINATES ABOVE 550 Hz. (Gautier and Dauchez, 2004).
SOUND RADIATION FROM A HARP SOUND POWER RADIATED BY THE SOUNDBOARD SURFACE (THIN LINE) AND BY THE SOUNDBOX HOLES (THICK LINE). IN THE REGIONS A,C, and E MORE POWER IS RADIATED THROUGH THE SOUND HOLES. IN B,D, and F, THE OPPOSITE IS TRUE (from Gautier and Dauchez, 2004).
SOUND RADIATION FROM SOUNDBOARD SURFACE SOUND RADIATION AT LOW FREQUENCY FROM THE SOUNDBOARD SURFACE (THIN LINE) AND THE SOUND HOLES (THICK LINE) (Gautier and Dauchez, 2004).
THOMAS ROYSTON AND HIS COLLEAGUES (CHICAGO) HAVE DEVELOPED COMPOSITE MATERIALS FOR HARPS. HARP BUILDER THOM (AUSTRALIA) BUILDS HARPS WITH ALUMINUM FRAMES AND ROSEWOOD SOUNDBOARDS ADARYN METATRON
BURMESE HARP THE BURMESE ARCHED HARP MAY HAVE COME FROM INDIA. THIRTEEN TO SIXTEEN SILK OR NYLON STRINGS RUN FROM A LONGITUDINAL CENTER RIB TO THE GRACEFULLY CURVED NECK. THE STRINGS ARE ATTACHED TO THE NECK BY CORDS THAT END IN DECORATIVE TASSELS. THE WRAPPED CORDS ARE TIGHTENED OR LOOSENED TO TUNE THE HARP. THEY ARE GENERALLY TUNED TO SCALES THAT RESEMBLE THE WESTERN DIATONIC SCALE BUT WITH THE THIRD AND SEVENTH NOTES LOWERED ABOUT A AQUARTER TONE. PRIOR TO THE NINETEENTH CENTURY, BURMESE HARPS WERE USED ONLY FOR CHAMBER MUSIC IN THE ROYAL COURT, WHERE IT WAS THE MOST PRIZED OF THE COURT INSTRUMENTS. IT WAS PLAYED AS A SOLO INSTRUMENT OR TO ACCOMPANY SINGERS
MAGNITUDES (UPPER) AND PHASE (LOWER) OF ACOUSTIC VELICITIES IN THE SOUND HOLES (LEFTHAND SCALE) AND SOUNDBOARD VELODITY (RIGHTHAND SCALE) FOR A CAMAC ATLANTIDE CONCERT HARP.