{"id":3504,"date":"2023-10-12T03:04:28","date_gmt":"2023-10-12T03:04:28","guid":{"rendered":"https:\/\/revolutionsincommunication.com\/viscomm\/?page_id=3504"},"modified":"2026-03-24T12:25:32","modified_gmt":"2026-03-24T12:25:32","slug":"digital-audio","status":"publish","type":"page","link":"https:\/\/revolutionsincommunication.com\/viscomm\/digital-audio\/","title":{"rendered":"Digital audio"},"content":{"rendered":"<p style=\"padding-left: 40px;\"><em>By Nick Kovarik\u00a0<\/em><\/p>\n<p style=\"padding-left: 40px;\"><span style=\"font-weight: 400;\">An <\/span><b>analog<\/b><span style=\"font-weight: 400;\"> recording resembles the waveform of the original sound; they are analogous, in other words. Audiotape, vinyl, and wax cylinders have a contiguous representation of a recorded waveform represented in its surface.<\/span><\/p>\n<p style=\"padding-left: 40px;\"><span style=\"font-weight: 400;\">A <\/span><b>digital<\/b><span style=\"font-weight: 400;\"> recording however is captured using a numerical representation of the original signal\u2019s frequency and amplitude. To do this, the <\/span><i><span style=\"font-weight: 400;\">frequency<\/span><\/i><span style=\"font-weight: 400;\"> and <\/span><i><span style=\"font-weight: 400;\">amplitude<\/span><\/i><span style=\"font-weight: 400;\"> of the signal are captured by an analog-to-digital (ADC) converter, such as a modern computer or its audio interface. Then to reproduce that signal, a digital-to-analog (DAC) is employed. A modern computer or phone has both, but in a high end audio world, sometimes external devices are still used. <a href=\"https:\/\/revolutionsincommunication.com\/viscomm\/wp-content\/uploads\/2019\/11\/increasing.sample.rates_.jpeg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignright size-medium wp-image-1768\" src=\"https:\/\/revolutionsincommunication.com\/viscomm\/wp-content\/uploads\/2019\/11\/increasing.sample.rates_-300x300.jpeg\" alt=\"\" width=\"300\" height=\"300\" srcset=\"https:\/\/revolutionsincommunication.com\/viscomm\/wp-content\/uploads\/2019\/11\/increasing.sample.rates_-300x300.jpeg 300w, https:\/\/revolutionsincommunication.com\/viscomm\/wp-content\/uploads\/2019\/11\/increasing.sample.rates_-150x150.jpeg 150w, https:\/\/revolutionsincommunication.com\/viscomm\/wp-content\/uploads\/2019\/11\/increasing.sample.rates_.jpeg 576w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/span><\/p>\n<p style=\"padding-left: 40px;\"><span style=\"font-weight: 400;\">In digital, <\/span><b>sampling<\/b><span style=\"font-weight: 400;\"> is the process of capturing the waveform over time with regards to the frequency, and <\/span><b>quantization<\/b><span style=\"font-weight: 400;\"> is the process of capturing the <\/span><i><span style=\"font-weight: 400;\">amplitude<\/span><\/i><span style=\"font-weight: 400;\"> at a snapshot in the sample.<\/span><\/p>\n<ul>\n<li aria-level=\"1\"><b>Sampling<\/b><\/li>\n<\/ul>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">The process of taking periodic samples (voltages) of the original signal at fixed intervals, the rate of which is known as the <\/span><b>sampling rate<\/b><span style=\"font-weight: 400;\">.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">Think of sampling as a video cameras <\/span><i><span style=\"font-weight: 400;\">frame rate.<\/span><\/i><span style=\"font-weight: 400;\"> The higher the sample rate, the more frames of definition we have in the product.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">The most common sampling rates are 44.1khz (early .mp3 quality) and 48khz (early dvd quality.) However, rates that double those (such as 88.2khz and 96khz) are also quite common. There are also ultra-high definition sample rates, such as 192khz, which is about as close to an analog signal as is necessary in everyday use.<\/span>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"3\"><span style=\"font-weight: 400;\">Sample rates outside of the ones above are very rare, as they are not easily converted to other sample rates.<\/span><\/li>\n<\/ul>\n<\/li>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">The <\/span><i><span style=\"font-weight: 400;\">Nyquist Theorem<\/span><\/i><span style=\"font-weight: 400;\"> states that to be successfully encoded, a signal has to be sampled at a rate at least twice its highest frequency. Consider capturing a 10hz frequency. If you were to sample that wave at 10hz, there would be no variation (compression \/ rarefaction) to the capture and it would produce no sound. Therefore, a sample rate of 20hz should capture the peak and trough of your waveform.<\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<ul>\n<li aria-level=\"1\"><b>Quantization<\/b><\/li>\n<\/ul>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">The number of bits taken per sample, more commonly referred to as <\/span><b>Bit Depth.<\/b><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"3\"><span style=\"font-weight: 400;\">The <\/span><i><span style=\"font-weight: 400;\">Bit Depth<\/span><\/i><span style=\"font-weight: 400;\"> affects the dynamic range of a wave, the underlying noise, and the distortion present in the recording.<\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p style=\"padding-left: 80px;\"><span style=\"font-weight: 400;\">Note: a 16 bit system has <\/span><span style=\"font-weight: 400;\">65,536 quantizing levels, and a 24 bit system has 16.8 million quantizing levels.\u00a0\u00a0<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><i><span style=\"font-weight: 400;\">Bit Depth <\/span><\/i><span style=\"font-weight: 400;\">affects the <\/span><b>Dynamic Range<\/b><span style=\"font-weight: 400;\"> of a recording.<\/span><\/li>\n<\/ul>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">The <\/span><i><span style=\"font-weight: 400;\">dynamic range<\/span><\/i><span style=\"font-weight: 400;\"> is the relationship between the quietest and loudest sounds inside a recording.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"3\"><span style=\"font-weight: 400;\">The <\/span><b>Signal to Noise Ratio (S\/N)<\/b> <i><span style=\"font-weight: 400;\">(also called the Noise Floor)<\/span><\/i><span style=\"font-weight: 400;\"> is the relationship between the quietest sounds in a recording and the underlying noise present.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"4\"><span style=\"font-weight: 400;\">Even in a recording space with no noise whatsoever (not usually possible on a budget) the system, from mics to cables to audio interface, adds noise at every stage, usually in very low manageable levels.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"4\"><span style=\"font-weight: 400;\">Note: in audio, noise is a broad term that refers to any unwanted sounds, such as background sounds and some types of distortion.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"3\"><span style=\"font-weight: 400;\">The <\/span><b>Headroom<\/b><span style=\"font-weight: 400;\"> is the relationship between the loudest sounds in a recording and the maximum amplitude your system can handle.<\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<ul>\n<li aria-level=\"4\"><b>Clipping<\/b><span style=\"font-weight: 400;\"> occurs when the amplitude of your signal overloads the system it is recorded on, typically represented by a red light on the audio channel. For digital recordings, this is <\/span><i><span style=\"font-weight: 400;\">digital distortion, <\/span><\/i><span style=\"font-weight: 400;\">and should be avoided wherever possible.<\/span><\/li>\n<\/ul>\n<ul>\n<li style=\"list-style-type: none;\">\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"4\"><span style=\"font-weight: 400;\">Some types of distortion are wanted in recordings. For example: The sound we associate with electric guitars, sometimes called <\/span><i><span style=\"font-weight: 400;\">overdrive,<\/span><\/i><span style=\"font-weight: 400;\"> is created by increasing the amplitude of a guitars signal to a level that early tube amplifiers could not handle. This is called <\/span><b>harmonic distortion,<\/b><span style=\"font-weight: 400;\"> and sounds MUCH better than digital distortion.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">In brief, the <\/span><i><span style=\"font-weight: 400;\">Bit Depth<\/span><\/i><span style=\"font-weight: 400;\"> of a recording is the resolution affecting the amplitude of a signal. While it does not guarantee an optimal noise floor or useful headroom, a higher Bit Depth allows more resolution to alter or correct minimal headroom and high S\/N.<\/span><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p style=\"padding-left: 80px;\"><span style=\"font-weight: 400;\">It is important to remember that for the end product of any media, the quality of your product can only ever be as good as the initial recording (and the sources recorded.) While aspects of poor quality recordings can be fixed or <\/span><i><span style=\"font-weight: 400;\">Masked<\/span><\/i><span style=\"font-weight: 400;\"> in post production, there is no way to increase resolution after a recording has finished. It always possible in Digital to reduce the output resolution when your destination requires smaller file sizes, and a high quality recording that has been reduced will usually sound better than a low quality recording that has remained the same.<\/span><\/p>\n<p style=\"padding-left: 80px;\"><span style=\"font-weight: 400;\">Additionally do not forget that your source is the most important stage of any production. There are songs that were recorded in garages that we still listen to today because they were amazing songs.\u00a0\u00a0<\/span><\/p>\n<h3>Typical Sample rates and bit depths<\/h3>\n<p>To summarize, sample rates and bit depth run from very high to very low quality.<\/p>\n<ul>\n<li><strong>Very high quality<\/strong> &#8212; 96,000 Hz sampling rate, 32-bit depth, usually used in studio recording. There are tradeoffs using this high rate, for example, higher speed\u00a0 computer processors and more storage space is needed.\u00a0 \u00a0 (See articles below).<\/li>\n<li><strong>Default recording quality<\/strong> &#8212; 44,100 Hz sampling rate, 32-bit depth, stereo audio file\u00a0 takes up about 20 MB of space per minute of audio.<\/li>\n<li><strong>CD quality<\/strong> &#8212; 44,100 Hz sampling rate, 16-bit, stereo\u00a0 takes up about 10 MB per minute.<\/li>\n<li><strong>Voice recording, low quality<\/strong> &#8212; 22,050 Hz, 8-bit, mono = 1.25 MB per minute. This would be generally acceptable for speech recordings from lower quality sources.<\/li>\n<\/ul>\n<hr \/>\n<h3>More<\/h3>\n<p><a href=\"https:\/\/www.izotope.com\/en\/learn\/digital-audio-basics-sample-rate-and-bit-depth.html\">Digital Audio basics<\/a> &#8211; Izotope<\/p>\n<p><a href=\"https:\/\/www.sweetwater.com\/insync\/should-i-record-at-the-high-sample-rates\">Should I record at high sample rates?\u00a0<\/a> Sweetwater, 2022<\/p>\n","protected":false},"excerpt":{"rendered":"<p>By Nick Kovarik\u00a0 An analog recording resembles the waveform of the original sound; they are analogous, in other words. Audiotape, vinyl, and wax cylinders have a contiguous representation of a recorded waveform represented in its surface. A digital recording however &hellip; <a href=\"https:\/\/revolutionsincommunication.com\/viscomm\/digital-audio\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":1781,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"full-width-page.php","meta":{"nf_dc_page":"","footnotes":""},"class_list":["post-3504","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/pages\/3504","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/comments?post=3504"}],"version-history":[{"count":4,"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/pages\/3504\/revisions"}],"predecessor-version":[{"id":3603,"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/pages\/3504\/revisions\/3603"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/media\/1781"}],"wp:attachment":[{"href":"https:\/\/revolutionsincommunication.com\/viscomm\/wp-json\/wp\/v2\/media?parent=3504"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}