Concepts and sound quality (foun.dig.med) Flashcards
What is the harmonic series?
Music comes from nature. The notes we use can be traced to an acoustical phenomenon known as the harmonic series. Whenever a musical pitch vibrates, we name that pitch for its fundamental (the most prominent pitch). However, the source of the sound will add acoustical impurities to it. Acoustic instruments create their sound by vibration, and in vibrating to one frequency, they pass through others. These other frequencies, or impurities, are actually other notes that can be heard faintly above the fundamental, and they are called overtones. The total sound of any note that you hear is a combination of all of these. We identify the note with a clear label, such as “C”, but this is actually the note’s average pitch.
The overtones follow a pattern called the harmonic series. Each of these notes have a different sound because each instrument has a different timbre. The acoustic guitar and piano have different timbres because each instrument will strengthen different parts of the harmonic series.
What are audio codecs?
Audio codecs are programs that compress data for transmission and decompress that data on the receiving end. Their speed is measured in thousands of bits processed per second, known as “bitrate” or “KBPS”, and this number varies even within a single format. Generally, a lower bitrate means a smaller file, but that also means more data (sound) is lost in compression.
What is sample rate?
The sample rate= the number of samples (signal amplitude or “sound”) per second. Sample rates are usually measured per second, using kilohertz (kHz) or cycles per second.
What is bit depth?
Bit depth = refers to the number of bits per sample . The higher the number, the fuller (and potentially louder) the sound. It describes the resolution of the sound data that is captured and stored in an audio file.
