《永無休止》

無聲之歌，無言之語，此刻醉臥靜穆中。

等待………

甦醒。

號角已響起，急而又急。

人間世，

一事尚且聽未清，一事早待看分明！

………

復黎明，

萬象交織光與影。

─── 《PD‧箱子世界‧休止♪》

 

理論與實務如何分殊？後浪和前浪可有界線？？講談原理所用的言語 ，是否就是寫作程式之語言？為什麼方便於此，卻老是為難於彼？？故耳雖知純數據擴張或成昨日，香草依舊還是芬芳！實難掩心情惆悵哩！！

就像過去樹莓派 2B 時，曾以 pd-extended  玩過變聲器︰

Pitch shift

Pitch shifting is a sound recording technique in which the original pitch of a sound is raised or lowered. Effects units that raise or lower pitch by a pre-designated musical interval (transposition) are called “pitch shifters” or “pitch benders”.

POG octave effect

Pitch/time shifting

The simplest methods are used to increase pitch and reduce durations, or vice versa, reduce pitch and increase duration. This can be done by replaying a sound waveform at a different speed than it was recorded. It could be accomplished on an early reel-to-reel tape recorder by changing the diameter of the capstan drive shaft, or using a different motor. As technologies improved later designs of motor speeds could be controlled by electronic servo system circuits. This arrangement using “vari-speed” capstan motors allowed the speed change to be achieved more simply.^[1] As for vinyl records, the same thing can be done; placing a finger on the turnable to give friction will retard it, while giving it a ‘spin’ can advance it.

Pitch shifter and harmonizer

A pitch shifter is a sound effects unit that raises or lowers the pitch of an audio signal by a preset interval. For example, a pitch shifter set to increase the pitch by a fourth will raise each note three diatonic intervals above the notes actually played. Simple pitch shifters raise or lower the pitch by one or two octaves, while more sophisticated devices offer a range of interval alterations. Pitch shifters are included in most audio processors today.

A harmonizer is a type of pitch shifter that combines the “shifted” pitch with the original pitch to create a two or more note harmony.

In digital recording, pitch shifting is accomplished through digital signal processing. Older digital processors could often only shift pitch in post-production, whereas many modern devices using computer processing technology can change pitch values virtually in real time.^[2]

Pitch correction is a form of pitch shifting and is found in software such as Auto-Tune to correct intonation inaccuracies in a recording or performance. Pitch shifting may raise or lower all sounds in a recording by the same amount, whereas in practice, pitch correction may make different changes from note to note.^[3]

 

如今恐不可復矣！★

近日偶讀

……

之

Pitch Shifting

I have just started learning about pitch shifting, and built my first pitch shifters in Pure Data object classes. This page will be dedicated to illustrations which pinpoint at typical bottlenecks of the topic.

Expanding or compressing a signal on the time-axis is a sure way to alter pitch. All frequency components are slowed down or sped up with the same ratio, and this will preserve their harmonic relations. This happens for example when playing a tape at slower or faster speed. Here is a visual impression of slowing down a waveform:

original wave

the same wave played at 3/4 of the speed

………

 

文章，恍惚之際倒陷反思勒？☆