{{Short description|Opening in the body of a stringed instrument}} {{For|parts of wind instruments|Tone hole}} [[Image:Cello study.jpg|thumb|right|The sound holes of [[cello]]s and other instruments of the [[violin family]] are known as F-holes and are located on opposing sides of the [[Bridge (instrument)|bridge]].]] A '''sound hole''' is an opening in the body of a [[string instrument|stringed]] [[musical instrument]], usually the upper [[Sound board (music)|sound board]]. Sound holes have different shapes: * '''Round''' in flat-top [[guitar]]s and traditional bowl-back [[mandolin]]s; * '''F-holes''' in instruments from the [[violin family]], archtop mandolins and in [[archtop guitar]]s; * '''C-holes''' in [[viola da gamba]]s and occasionally [[double-basses]] and [[guitars]] * '''[[rosette (music)|Rosette]]s''' in [[lute]]s and sometimes [[harpsichord]]s; * '''D-holes''' in [[Byzantine lyra|bowed lyras]]. Some instruments come in more than one style ([[mandolin]]s may have F-holes, round or oval holes). A round or oval hole or a rosette is usually a single one, under the strings. C-holes, D-holes and F-holes are usually made in pairs placed symmetrically on both sides of the strings. Most [[Hollowbody electric|hollowbody and semi-hollow]] [[electric guitars]] also have F-holes.
Though sound holes help [[acoustic instrument]]s project sound more efficiently, sound does not emanate solely from the sound hole. Sound emanates from the [[surface area]] of the sounding boards, with sound holes providing an opening into the [[acoustic resonance|resonant chamber]] formed by the body, letting the sounding boards [[oscillation|vibrate]] more freely, and letting vibrating air inside the instrument travel outside the instrument. The F-holes in the violin family instruments also serve the purpose of enabling a [[luthier]] to use specialized tools to adjust the [[sound post]] inside the instrument.
In 2015, researchers at [[Massachusetts Institute of Technology|MIT]], in collaboration with [[Luthier|violin makers]] at [[North Bennet Street School]], published an analysis that charted the evolution and improvements in effectiveness of violin F-hole design over time.<ref>{{Cite web|url=https://news.mit.edu/2015/violin-acoustic-power-0210|title=Power efficiency in the violin|website=MIT News | Massachusetts Institute of Technology|date=10 February 2015 }}</ref><ref>{{Cite journal|title=The evolution of air resonance power efficiency in the violin and its ancestors|first1=Hadi T.|last1=Nia|first2=Ankita D.|last2=Jain|first3=Yuming|last3=Liu|first4=Mohammad-Reza|last4=Alam|first5=Roman|last5=Barnas|first6=Nicholas C.|last6=Makris|date=March 8, 2015|journal=Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume=471|issue=2175|article-number=20140905|doi=10.1098/rspa.2014.0905|pmid=25792964|pmc=4353046|bibcode=2015RSPSA.47140905N}}</ref> One of the conclusions of this paper was that acoustic conductance (air flow) is proportional to the length of the perimeter of the sound hole and not the area. They proved this mathematically, and showed how it drove the evolution of shape of the F-holes in the violin family. The highest air flow in a violin's F-hole are the places at the top and bottom where the points nearly touch the other side. The effect is analogous to putting one's thumb over the end of a hose to accelerate the water coming out. By this measure, the open round hole of a flat-top acoustic guitar is not very effective.
==Alternative sound hole designs== Some [[Ovation Guitar Company|Ovation]] stringed instruments feature a particularly unique sound hole architecture with multiple smaller sound holes that, being combined with a [[composite material|composite]] bowl back body, are said to produce a clear and bright sound.
[[Tacoma Guitars]] has developed a unique "paisley" sound hole placed on the left side of the upper bout of their "Wing Series" guitars. This is a relatively low-stress area that requires less bracing to support the hole.<ref>{{Cite web |last=Salter |first=Trent |date=2004-04-13 |title=interview with Leith Anderson |url=http://www.musicianshotline.com/archive/interviews/tacoma_guitars.htm |archive-url=https://web.archive.org/web/20040413010556/http://www.musicianshotline.com/archive/interviews/tacoma_guitars.htm |archive-date=2004-04-13}}</ref>
A few hollowbody or semi-hollow [[electric guitar]]s, such as the [[Fender Telecaster Thinline]] and the [[Gibson ES-120T]], have one f-hole instead of two, usually on the bass side.
B&G Guitars, a private build guitar company from Tel Aviv, Israel, uses their signature "backwards" sound holes on their guitars.<ref>{{Cite web|url=https://www.bngguitars.com/|title=B&G Guitars|website=B&G Guitars}}</ref>
Holes not positioned on the top of an [[acoustic guitar]] are called '''soundports'''. They are usually supplementary to a main sound hole, and are located on an instrument's side facing upward in playing position, allowing players to monitor their own sound.<ref>{{Cite web |url=http://www.parkguitars.com/q-soundport-effect/ |title=Q. What is the effect of the soundport? | Shelley D. Park Guitars :: Gypsy Jazz Guitar Luthier in the Style of Selmer Maccaferri |date=May 15, 2008 |website= |archive-url=https://web.archive.org/web/20080515125503/http://www.parkguitars.com/q-soundport-effect/ |archive-date=15 May 2008 }}</ref>
===Gallery=== <gallery> File:Gibson L-5 CES.jpg|F-holes on a [[Gibson L-5]] [[archtop guitar]] File:Fender 72 Telecaster Thinline.png|Single F-Hole on a [[Fender Telecaster Thinline]] guitar File:Ovation.jpg|Leaf sound hole in an [[Ovation Guitar Company|Ovation Adamas]] guitar File:Pattern on Acoustic Guitar.JPG|Many acoustic guitars incorporate [[rosette (design)|rosette patterns]] around the sound hole. File:Guitares type Selmer Maccaferri.jpg|[[Maccaferri guitar]]s have D or oval shaped sound holes. File:Cc guitar acoustic electric calligraphy series dragon.jpg|Unique Sound Hole with [[Chinese character]] [[wikt:龙|龙]] by Cc Guitar [http://commons.wikimedia.org/wiki/File:Cc_guitar_acoustic_electric_calligraphy_series_dragon.jpg] File:GambeUilderks.png|C-holes on a [[viol]] File:Mongolian_horsehair-horsehead_fiddles_WOMADelaide_festival_Adelaide_AUSTRALIA_March_2012.jpg|Two [[Morin Khuur]]s with two F-holes </gallery>
==References== {{Reflist}}
==External links== *[https://web.archive.org/web/20051013054747/http://www.stringworks.com/instrument_construction.htm Stringworks U] - brief explanation of the effects of sound holes, with a closeup diagram of an F-shaped soundhole
{{Violin family}} {{Authority control}}
[[Category:String instrument construction]] [[Category:Guitar parts and accessories]] [[Category:Holes]]