| 词条 | A440 (pitch standard) |
| 释义 |
A440 or A4 (also known as the Stuttgart pitch), which has a frequency of 440 Hz, is the musical note of A above middle C and serves as a general tuning standard for musical pitch. The International Organization for Standardization classifies it as ISO 16. Before standardization on 440 Hz, other frequencies were standardized upon. Although not universally accepted, it serves as the audio frequency reference to calibrate acoustic equipment and to tune pianos, violins, and other musical instruments. History and useBefore standardization on 440 Hz, many countries and organizations followed the French standard since the 1860s of 435 Hz, which had also been the Austrian government's 1885 recommendation.[1] Johann Heinrich Scheibler recommended A440 as a standard in 1834 after inventing the "tonometer" to measure pitch,[2] and it was approved by the German Natural History Society the same year.[3] The American music industry reached an informal standard of 440 Hz in 1926, and some began using it in instrument manufacturing. In 1936 the American Standards Association recommended that the A above middle C be tuned to 440 Hz.[4] This standard was taken up by the International Organization for Standardization in 1955 (reaffirmed by them in 1975) as ISO 16.[5] It is designated A4 in scientific pitch notation because it occurs in the octave that starts with the fourth C key on a standard 88-key piano keyboard. On MIDI, it is note 69. A440 is widely used as concert pitch in the United Kingdom[6] and the United States.[7] In continental Europe the frequency of A4 commonly varies between 440 Hz and 444 Hz.[6] In the period instrument movement, a consensus has arisen around a modern baroque pitch of 415 Hz (with 440 Hz corresponding to A{{music|sharp}}), baroque for some special church music (Chorton pitch) at 466 Hz (with 440 Hz corresponding to A{{music|flat}}), and classical pitch at 430 Hz.[8] {{Listen|filename=Sine wave 440.ogg|title=A440|description=5 seconds of sine wave at 440 Hz|format=Ogg}}A440 is often used as a tuning reference in just intonation regardless of the fundamental note or key. The US time and frequency station WWV broadcasts a 440 Hz signal at two minutes past every hour, with WWVH broadcasting the same tone at the first minute past every hour. This was added in 1936 to aid orchestras in tuning their instruments.[9] See also
References1. ^{{cite book | title= Dictionary of Music | last= Karp | first= Theodore | publisher= Northwestern University Press | year= 1983 | isbn= 9780810106598 | url={{google books | id= G3bHp9WXRQAC | page= 406 | plainurl= yes}} | page= 406}} {{ISO standards}}{{Pitch (music)}}2. ^{{cite book | title = Sounds of our times: two hundred years of acoustics | author = Robert Thomas Beyer | publisher = Springer | year = 1999 | isbn = 978-0-387-98435-3 | page = 32 | url = https://books.google.com/books?id=kebDOljfX7oC&pg=PA32&dq=Johann+Scheibler&ei=kNDjStanBJi-lASUwoH3Cw#v=onepage&q=Johann%20Scheibler&f=false}} 3. ^Helmholtz, Hermann von (1863). [https://books.google.com/books?id=siRDAAAAcAAJ&pg=PR3#v=onepage&q=Scheibler&f=false Die Lehre von den Tonempfindungen als physiologische Grundlage für die Theorie der Musik], p.29. J. Vieweg. {{pre-ISBN}}. 4. ^{{cite book | title= The Opera Companion | first= George | last= Martin | publisher= Hal Leonard Corporation | year= 2008 | isbn= 978-1-57467-168-1 | url= {{google books | id= MjTLYqOoi3kC | page= 92 | keywords= 440-cps 1936 | plainurl= yes}}}} 5. ^{{cite book | title= ISO 16:1975 Acoustics – Standard tuning frequency (Standard musical pitch) | publisher= International Organization for Standardization | year= 1975 | url= http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=3601}} 6. ^1 {{cite web | first= Franz | last= Nistl | url= http://members.aon.at/fnistl/page3.html | title= Europa E - SK | work= Klavierstimmung}} 7. ^{{cite web | first= Franz | last= Nistl | url= http://members.aon.at/fnistl/page4.html | title= Afrika Amerika Asien Ozeanien | work= Klavierstimmung}} 8. ^Oxford Composer Companion JS Bach, page 369–372. Oxford University Press, 1999 9. ^{{cite web | title= History of WWV | publisher= Physical Measurement Laboratory, NIST | date= September 16, 2015 | url= https://www.nist.gov/pml/div688/grp40/wwv-history.cfm}} 2 : ISO standards|Musical tuning |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。