# Digital Audio Fundamentals ## What is digital audio? Digital audio refers to the representation of sound in a digital format, wherein audio signals are converted into a series of binary numbers that can be stored, transmitted, and manipulated by electronic devices such as computers and audio processors. Unlike analog audio, represented by continuously varying electrical signals, digital audio breaks down sound into discrete samples at regular intervals, typically measured in thousands of samples per second (expressed as KHz[^1]). Each sample captures the amplitude of the audio waveform at a specific point in time, allowing for precise reproduction and manipulation of sound. Digital audio has revolutionized how we record, edit, transmit, and reproduce sound, enabling unprecedented levels of fidelity, flexibility, and convenience in a wide range of applications, from music production and broadcasting to telecommunications and multimedia entertainment. *** ## Conversion process Recording or converting sound into a digital format involves two primary steps: **sampling** and **quantization**. ### **Sampling** Sound is a continuous analog wave. To digitize this sound, it is sampled at discrete intervals. The sampling rate, measured in Hertz (Hz), defines how many times per second the sound is sampled. A common sampling rate for CD-quality audio is 44.1 kHz, meaning the audio is sampled 44,100 times per second. In broadcast video production, the sample rate is 48 kHz; for high-quality audio recording and mastering, the sample rate can be up to 768 kHz. ### **Quantization** Once sampled, each snapshot of the sound's amplitude is converted into a digital value. This process is known as quantization. The bit depth determines the resolution of this conversion, with higher bit depths allowing a more precise representation of the sound's amplitude. Common bit depths include 16-bit, 24-bit, and 32-bit. *** ## Audio formats In addition to the fundamental concepts of sampling and quantization, understanding digital audio involves familiarity with various audio file formats. These formats can be categorized into two main types: **uncompressed** and **compressed**. ### **Uncompressed Formats** These formats store digital audio data without any compression, preserving the original quality of the audio. Common uncompressed audio formats include: **WAV (Waveform Audio File Format)**: Developed by IBM and Microsoft, it's a standard format for storing audio on PCs. **AIFF (Audio Interchange File Format)**: Developed by Apple, similar in quality and structure to WAV, commonly used on Mac computers. ### **Compressed Formats** Compressed formats store audio data using algorithms that eliminate redundant or less audible information to reduce file size. Compressed formats can be lossless or lossy. **Lossless Formats**: These compress audio data without losing any information, allowing the original audio to be perfectly reconstructed from the compressed data. Examples include FLAC (Free Lossless Audio Codec) and ALAC (Apple Lossless Audio Codec). [^1]: In the context of sound, **kilohertz** represents the frequency of audio signals. It refers to the number of times a sound wave oscillates per second. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.ndi.video/all/using-ndi/ndi-for-audio/digital-audio-fundamentals.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.