Talk:ITU-R 468 noise weighting

Spelling corrections appreciated thanks - most were due to the fact that I have not yet worked out how to disable the touch-pad on my new laptop and my double-jointed thumb hits it as I touch type!

Removal of capitalisation in title also appreciated - I realised my error (new to this) and was trying to work out how to alter it.

I was in two minds about using ITU in the title. One argument says that this is still a CCIR standard in the sense that it was originated by them, though it is true the ITU took over its maintenance. Many references will still be to CCIR-468, but I guess this is best coped with by linking.

I do not like the external reference added, as much of it is not true, such as the reasons why CCIR-468 came into existence, and the reference to 'intrusiveness of noise' which my article makes clear is not what it is about - it's just loudness. Any comments on this?
 * It is not just loudness, it is trying to associate a signal with a perceived disturbance, as described in the cited Belger paper. Loudness is appropriate where one wishes to determine the audibility of a weak signal, i. e. the loudness of programme content. Measuring noise in the presence of programme is a different question.

INFORMATION FROM ANYONE WITH DIRECT KNOWLEDGE OF THE ORIGINS OF CCIR-468 would be valuable. I have gone to some lengths to research this, but information about how and why it was devised is hard to come by. Lindosland
 * The references to BBC and the Belger paper are appropriate. Belger was working for Siemens at the time developing a noise level meter and the paper describes how it can be applied to measure how annoying the noise is.

I've added an image with three graphs (Lindos1.svg) which was created 10cm wide in Openoffice Draw, but cannot work out how to make it come bigger. tried thumb|400px but it doesn't work! Help please? Lindosland 18:32, 30 November 2005 (UTC)

Image Problems
The SVG image now works using thumb|400px but I don't understand why it has a blue background (normally white - not transparent as far as I know).

Ah, done it, Draw has problems with narrow linewidths, when export to SVG. Lindosland 19:46, 30 November 2005 (UTC) 468 is a good weighting scheme for loudness judgements in listening tasks, such as music, but it isn't superior for some other tasks, such as measuring the damaging effect to hearing exposure. You clearly are very proud of the BBC (rightly so), but this article would be better if the factual content were retained while removing the editorializing about how people must be stupid if they don't use 468.


 * Why would anyone use a noise weighting curve to assess hearing damage? That would indeed be stupid, as there is no reason at all to suppose that there is any correlation between apparent loudness and damage. I stick to my argument that 468 is the only curve actually designed for noise assessment, for reasons given, and that A-weighting is very wrong for the job (it doesn't even have a proper HF rolloff anything like that of the equal-loudness contours). Assessing music is something yet again, and since it is sometimes noise-like and sometimes pure tones it really needs something more complex than a weighting curve, based on proper combination of the outputs of a bank of narrow band filter. --Lindosland 20:21, 25 November 2006 (UTC)


 * Agree with Lindosland, I don't think the suitability of 468 measurements for noise in the presence of signal is disputed. For instance, it has always been specified as the required standard for the evaluation of inherent noise in microphones (IEC 60268-4). My understanding is that this approach, as described in the history section of the article, was initially developed by the DBP to assess feedthrough of switching transients from one circuit to another of a telephone multiplex circuit. It was called out as the preferred noise floor measurement standard for microphones in standards as early as the DIN 45 500 series in the early 1970s. But it is intended only for the quantification of the annoyance caused by undesired noise under a desired signal, not to estimate total loudness or potential for hearing damage. DLJosephson (talk) 19:23, 26 August 2009 (UTC)

The SVG files on this article as well as [A-weighting] are not displaying correctly. I would recommend the author converts them to a more standardized format that a wide variety of browsers can correctly display, such as JPG, bitmap, or PNG. I've tried loading the pages on IE, Firefox, and Chrome and I get the same results with all browsers. 74.92.147.125 (talk) 21:15, 2 March 2009 (UTC)

Advocacy stance
This article expresses a definite preference for the use of 468 rather than "A" weighting in noise measurements. I happen to agree, but such editorial opinion is out of place in a Wikipedia article. We can present the advantages of something without being conclusory ("Nevertheless, 468-weighting is still demanded by the BBC and many other broadcasters, and knowledge of its existence and validity needs to spread. It is superior in allowing fair comparison of specifications for all types of equipment ..."). DSatz 02:42, 19 May 2007 (UTC)


 * I agree, my Wikipedia editing skills with regard to NPOV and OR etc having come on enormously as a result of hundreds of hours editing many other (non-engineering) topics since the early days when I created this and associated articles! I did create those early articles by first copying articles I had written for other purposes. It was an effective way of adding greatly to a Wikipedia which was then much less refined, quickly. I would not do that now. Regards --Lindosland (talk) 16:55, 9 April 2008 (UTC)


 * IEC standards, for instance 60268-4 on microphones, require 468/quasi-peak measurements while allowing A-weighted in addition. It is not an editorial opinion to refer to the preference stated in an international standard, is it? Altaphon (talk) 01:44, 9 March 2011 (UTC)

I have removed the piece about 468 measurements being easier, etc. Both of these comments are simply mistaken. Microphone performance measurements are typically done in accordance with the applicable international standard, IEC 60268-4. DLJosephson (talk) 19:59, 29 February 2012 (UTC)

WikiProject class rating
This article was automatically assessed because at least one WikiProject had rated the article as start, and the rating on other projects was brought up to start class. BetacommandBot 09:54, 10 November 2007 (UTC)


 * I have upgraded to C-class for well-written content. Major work on citations required to go higher. Areas requiring references are well marked inline. I've assigned a Low importance because not much showed up when I searched in books or on the web. --Kvng (talk) 23:11, 12 July 2011 (UTC)