{"id":41843,"date":"2024-02-14T15:52:28","date_gmt":"2024-02-14T20:52:28","guid":{"rendered":"https:\/\/www.tedpublications.com\/fr\/?p=41843"},"modified":"2024-02-14T15:52:28","modified_gmt":"2024-02-14T20:52:28","slug":"most-audio-rooms-are-lousy","status":"publish","type":"post","link":"https:\/\/www.tedpublications.com\/fr\/en\/most-audio-rooms-are-lousy\/","title":{"rendered":"Most Audio Rooms are Lousy"},"content":{"rendered":"<p><span style=\"font-family: helvetica;\">It seems that most high-end audio people focus more on the electronic equipment than on what has the most influence on the end result\u00a0\u2014 room acoustics. When I say room acoustics, it also includes the physical and electrical calibration of the equipment. Together it is a system, and when optimized, allows the equipment to perform at its full potential, and deliver a much greater experience.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">Remember, the equipment cannot control the acoustics, and the acoustics does not care what kind of equipment you have. Remember also that DSP \u201croom correction\u201d is very limited, as it only alters the electrical signal feeding the loudspeakers. Once that signal leaves the speaker, it is a sound wave, whose energy is now at the mercy of the room\u2019s acoustics.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">How bad is the typical home theater or two channel listening room? Typically, bad enough that getting new equipment will have little to no bearing on improved performance. That is not to say that new equipment may make your system sound different, for better or worse, it is to say that the \u201cfidelity\u201d characteristics of the room will not be changed. The room has the same distortions interfering with fidelity.<\/span><\/p>\n<p><strong><span style=\"font-family: helvetica;\"><em>Consider the following:<\/em><\/span><\/strong><\/p>\n<ul>\n<li><span style=\"font-family: helvetica;\">Most audio listening rooms vary in <strong>frequency response<\/strong> by more than 20\u00a0dB SPL across the audible spectrum.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Most audio listening rooms vary in <strong>reverberation times<\/strong> by more than 1\u00a0second across the audible spectrum.<\/span><\/li>\n<\/ul>\n<p><strong><em><span style=\"font-family: helvetica;\">Do you think a better amplifier or pre-amplifier would have any impact?<\/span><\/em><\/strong><\/p>\n<ul>\n<li><span style=\"font-family: helvetica;\">Most audio listening rooms have an <strong>ambient noise floor<\/strong> of around 40\u00a0dB SPL.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Most audio listening rooms have only about 60\u00a0dB of <strong>usable<\/strong> <strong>dynamic range<\/strong>.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Most audio listening rooms have very <strong>audible early decay times<\/strong>.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Most audio rooms have <strong>room modes <\/strong>that swing more than 20\u00a0dB SPL.<\/span><\/li>\n<\/ul>\n<p><em><strong><span style=\"font-family: helvetica;\">Maybe some new speakers will help?<\/span><\/strong><\/em><\/p>\n<ul>\n<li><span style=\"font-family: helvetica;\">Most audio listening rooms have <strong>1<sup>st<\/sup>order reflections <\/strong>within 10\u00a0dB of the direct signal.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Most multi-channel audio systems are currently performing with <strong>calibration errors<\/strong> as bad as; channel ID incorrect, polarity on one channel reversed, a dead driver, polarity reversed on a driver, not to mention poor speaker\u00a0\/\u00a0listening locations, positioning, alignment, etc.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-family: helvetica;\">Would investing in, say, an expensive power cable really be the smartest next move toward audio nirvana? It is silly to think that micro changes in electronics can be beneficial prior to addressing macro problems in the system.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">The sound quality hierarchy is: set-up, calibration, acoustics, electronics. State-of-the-art equipment will not sound good in a poor environment- heck, mid-fi equipment in a good environment will beat it every time.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\"><strong><img loading=\"lazy\" decoding=\"async\" class=\"size-large wp-image-41847 aligncenter\" src=\"https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/Dynamic-Range-451x550.jpg\" alt=\"\" width=\"451\" height=\"550\" srcset=\"https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/Dynamic-Range-451x550.jpg 451w, https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/Dynamic-Range.jpg 481w\" sizes=\"auto, (max-width: 451px) 100vw, 451px\" \/><\/strong><\/span><br \/>\n<span style=\"font-family: helvetica;\"><em>This graphic depicts the typical audio room noise floor and available dynamic range. Imagine all the low-level details that cannot be heard by the noisy environment.<\/em><\/span><\/p>\n<p><span style=\"font-family: helvetica;\">The ambient noise floor consists of HVAC, appliance\u00a0\/\u00a0equipment noise, plumbing, outside noise, etc. There are a number of things that can be done to prevent or mitigate these noises and distractions from covering up the low-level information. Often with music, and especially with movies, low-level information is critical to the story telling, offering clues and cues, and triggering emotions, offering suspense and relief, etc.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"size-large wp-image-41849 aligncenter\" src=\"https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/5-Avg-RT60-890x509.jpg\" alt=\"\" width=\"890\" height=\"509\" srcset=\"https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/5-Avg-RT60-890x509.jpg 890w, https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/5-Avg-RT60-647x370.jpg 647w, https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/5-Avg-RT60-768x439.jpg 768w, https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/5-Avg-RT60.jpg 927w\" sizes=\"auto, (max-width: 890px) 100vw, 890px\" \/><br \/>\n<span style=\"font-family: helvetica;\"><em>This graphic represents the average reverberation times of fifty audio rooms I worked on before acoustically treating. Do you think there might be speech intelligibility issues, poor imaging and spatial cues, buried low-level information, timbre errors, and inarticulations?<\/em><\/span><\/p>\n<p><span style=\"font-family: helvetica;\">Reverberation times are pretty easy to address, even with existing rooms. It is common these days for rooms to consist of large, hard surfaces, which allow sound to bounce around and linger. Besides acoustic absorption panels, there are furnishings that can absorb sound energy, like curtains, carpet or area rugs, fabric covered chairs and sofas, etc. For rooms that are too dead, diffusers can be introduced to bring some life back, and\u00a0\/\u00a0or make the room sound bigger.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">In both cases, it is important to try to attenuate the first reflections of each speaker on each surface. Placing absorbers or diffusers in these locations will improve soundstage, timbre and spatial cues. Once this is controlled, address the remaining reverberation curve (time over frequency) until it is controlled for a linear response within a time window of about 0.25 second from 125 Hz. and up, with a slightly ascending decay rate below 125 Hz. This will offer the most neutral and pleasing sound<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"size-large wp-image-41851 aligncenter\" src=\"https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/RT60-AB-copy-544x550.jpg\" alt=\"\" width=\"544\" height=\"550\" srcset=\"https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/RT60-AB-copy-544x550.jpg 544w, https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/RT60-AB-copy-640x647.jpg 640w, https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/RT60-AB-copy-45x45.jpg 45w, https:\/\/www.tedpublications.com\/fr\/wp-content\/uploads\/2024\/02\/RT60-AB-copy.jpg 763w\" sizes=\"auto, (max-width: 544px) 100vw, 544px\" \/><\/p>\n<p><span style=\"font-family: helvetica;\"><em>This graphic shows actual before and after acoustic treatment results of a media room. Notice that when the reverberation times are controlled that the sound does not vary as much seat to seat. This room was unusable, and now sounds outstanding.<\/em><em><br \/>\n<\/em><\/span><br \/>\n<span style=\"font-family: helvetica;\"><strong>What are we trying to achieve?<br \/>\n<\/strong>There are specific room acoustic goals to attain and in doing so mean peak equipment performance and enjoyment. The primary ones are:<\/span><\/p>\n<p><span style=\"font-family: helvetica;\"><strong><u>Characteristic <\/u><\/strong><strong>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <u>Avg. Audio Room <\/u>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 <u>Desired<\/u><\/strong><\/span><\/p>\n<p><span style=\"font-family: helvetica;\">Ambient Noise Foor\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 40\u00a0dBA\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 18 dBA<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">Dynamic Range\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 60\u00a0dB\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 82 dB<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">Reverberation Times \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Freq. varies &gt;\u00a01\u00a0sec \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0varies &lt;\u00a00.4\u00a0sec.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">Room Modes \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0+\/-\u00a012\u00a0dB or &gt; \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 +\/-\u00a05\u00a0dB<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">Vibration isolation\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 None \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0&gt;\u00a090\u00a0% mitigated<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">In addition to elevating the performance to a much higher level than any new piece of equipment could do, acoustic control means neutrality and accuracy of the sound. Now you can judge equipment and recordings more faithfully. An accurate room is always a more enjoyable listening experience. Every room sounds unique, unless it is controlled.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\"><strong>How is this done?<\/strong><\/span><br \/>\n<span style=\"font-family: helvetica;\">We wil go into details in further articles, but the quick answer is the following steps:<\/span><\/p>\n<ol>\n<li><span style=\"font-family: helvetica;\">Understand the existing conditions. If existing construction, this is done with acoustic tests performed onsite. If new construction, the anticipated conditions must be estimated with computer modeling.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Understand the desired conditions or goals.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Computer model solutions (acoustical products) to get from the existing to the desired.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Make and apply the recommendations.<\/span><\/li>\n<li><span style=\"font-family: helvetica;\">Test onsite to confirm or adjust the treatments.<\/span><\/li>\n<\/ol>\n<p><span style=\"font-family: helvetica;\">Note that acoustic recommendations cannot be done without acoustic data. Room dimensions and layout alone does not include any of the fundamental acoustic characteristics we are trying to control. Without knowing the existing or estimated conditions, it is impossible to make recommendations. It is a specific prescription for specific and unique problems. Your room is different from everyone else\u2019s, <strong><em>and<\/em><\/strong> it has different constraints. Only onsite tests or sophisticated computer modeling to estimate the conditions will give you workable data to formulate solutions. There is recent technology that allows customers to take an impulse response of the room and email me the WAV file. I can then look at the data from any combination of frequency, time, and energy domain I need. It will also capture the noise floor and many other attributes. This is about 75\u00a0% as good as me being there conducting tests myself, but for about half the cost.<\/span><\/p>\n<p><span style=\"font-family: helvetica;\">I hope that reading this article has impressed upon you the importance of room acoustics over electronic equipment upgrades, and that there are means of organizing chaotic sound in a scientific manner. The course adjustments must be made before the fine. My last point to make is that typically, the cost of acoustic improvements is a fraction of equipment upgrades, and yet they will have many times greater sonic impact.<\/span><\/p>\n<p><span style=\"font-family: helvetica; color: #800000;\"><a style=\"color: #800000;\" href=\"https:\/\/avroomservice.com\/evp-2\/\" target=\"_blank\" rel=\"noopener\"><strong>https:\/\/avroomservice.com\/evp-2\/<\/strong><\/a><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>It seems that most high-end audio people focus more on the electronic equipment than on what has the most influence on the end result\u00a0\u2014 room acoustics. When I say room acoustics, it also includes the physical and electrical calibration of the equipment. Together it is a system, and when optimized, allows the equipment to perform [&hellip;]<\/p>\n","protected":false},"author":154722,"featured_media":41846,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2723,2707,2725],"tags":[],"class_list":["post-41843","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hifi","category-home-theater","category-whats-new","entry","has-media"],"_links":{"self":[{"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/posts\/41843","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/users\/154722"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/comments?post=41843"}],"version-history":[{"count":6,"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/posts\/41843\/revisions"}],"predecessor-version":[{"id":41854,"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/posts\/41843\/revisions\/41854"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/media\/41846"}],"wp:attachment":[{"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/media?parent=41843"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/categories?post=41843"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tedpublications.com\/fr\/wp-json\/wp\/v2\/tags?post=41843"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}