| Nowaday,almost all fields need computer technology support,music also has a lot of achievements in the use of computers technology.In recent years,computers have been widely used in instrument sound tuning.However,all research results and softwares are all supporting pitch tuning.Some piano producers exist checking whether the sound of the instrument is standard,sweet,loud enough,clear enough,whether sound duration is long enough and so on,because of that,we need some method of adjusting piano structure and making piano’s material selection to have the best and the most standard sound of the piano.However,current softwares can not meet these requirements,therefore research on tuning piano sound characteristic(such as timbre,sound intensity,sound length,etc.)not only has great meaning for piano manufacturer,but also help ordinary users to check piano sound whether standard.First of all,this thesis introduces development history of computer music.This partpresentChina and international piano tuning research and software current development condition,as well as the specific working principle of instrumental tuning and piano tuning.In main content,firstly,we mention pitch tuning,this section introduces sound wave’s basic knowledge,followed by frequency,spacing,human perception,the relationship of pitch and frequency also the fundamental frequency.As well as some impact of physiological and physical characteristics on sound pitch.In view of the current research on the extraction of pitch is quite perfect,and there are so many good piano tuning software now,so this thesis only discusses some existing algorithms to extract pitch of sound,and choose the most suitable for the implementation of piano pitch tuning algorithm through the experiment.The second is research on assistant piano sound timbre tuning.This section describes the definition of sound timbre,timbre characteristic and relationship between timbre characteristics and frequency.Through relevant research,let reader understands deeply about spectrum and spectrogram.In this thesis,two pianos sound timbre tuning assistant methods are proposed.They are timbre recognition and timbre comparison method,and also,the advantages and disadvantages of these two methods are discussed.The timbre recognition method uses timbre characteristic patterns to identify timbre of tuning sound.This thesis also describes some algorithms for timber recognition.On timbre comparison method,this thesis presents a new method,that is,the use of fuzzy mathematics close degree to compare the two sound spectrum,we can compare a frequency band of two sound in the same period of time.With this method we can get correct and detailed results,also is not limited by the number of timbre characteristic pattern.Finally is Piano sound intensity,sound length tuning.This section firstly introduce sound intensity,sound length and theirs related theory,and the next is methods of calculating sound intensity.To compare two pianos sound’s loudness,we can not compare directly two sound intensity values while should compare two sounds intensity change process,because the sound intensity is affected by space distance and the environment so much.In this thesis,I propose fuzzy mathematics close degree to compare the two sound intensity changes process.According to five fuzzy close degree algorithm,six cases of sound intensity changes process are experimented to find out the most suitable for sound intensity comparison.It is the maximum and minimum close degree method.With sound length tuning supporting,this thesis just simply compares the two sounds broadcast time. |
