He enlisted the support of his former songwriting partner, Sir Tim Rice, to claim that the UK Top 40 is now little more than a guide to the most successful record company marketing departments, and that most companies treat the public with "near contempt".
Lord Lloyd-Webber's mission does not derive purely from public spiritedness. He was furious that the record company multinational Polygram cut by one penny the price of the Boyzone single "No Matter What", taken from his musical Whistle Down The Wind. The cut, to pounds 1.78, after a long run at number one, put the single below the threshold for further inclusion in the charts.
Polygram cut the price to make way for another Boyzone single. If it had remained in the charts, the record would probably have become the biggest-selling single of the year.
Lord Lloyd-Webber's assault on pop chart and record company integrity would have been of significance by itself. But yesterday he produced an equally significant co-complainant - his erstwhile lyricist,Sir Tim Rice. Study of the pop charts may be far from an academic discipline; but few students command more respect than Sir Tim, an author and expert on the charts for two decades.
Their other accusations, not of illegality or chart rigging, but chart manipulation, will alert the public to the way the charts have changed.
The most common manipulation of the charts is by companies selling "two for one" to the retailer - selling a single at full price and giving the shop another copy of the same title free. Discounting some singles is also increasingly common.
John McKie, editor of Smash Hits, points out that another common method is to "release" a song to radio stations some six weeks before the official release date, so record buyers snap it up in the first week, as they already feel they know it well. Sales then fall rapidly.
However, he adds that Cher's seven-week run at the top of the charts disproves the Lloyd Webber/Rice assertion about singles being purely quickfire album trailers. And singles have created recent stars such as Billie and Steps.
But Eugene Beer, a former record plugger to national radio, says: "Andrew Lloyd Webber is absolutely right. The charts have never been more ridiculous. You only have to sell 20,000 copies to get in. No one makes money out of singles; they are almost entirely for promoting albums."
The retailers disagree. A spokesman for HMV said: "People get very sentimental about the charts. But in fact they have never been more accurate. Yes, marketing techniques are taken to the ultimate level, but we now have a price ruling which stops singles being released for absurdly low prices and distorting the charts."
Lord Lloyd-Webber and Sir Tim Rice wrote in their letter to The Times yesterday: "For nearly half a century the British pop music charts have provided an accurate, informative and enjoyable guide to the most popular recordings of the day.
"Whether a song remained in vogue for six months or one week, its standing with the affections of the public was faithfully and honestly recorded.
"Over the past few years this tradition has been destroyed by the majority of this country's record companies.
"[Polygram], clearly believing that neither they nor Boyzone can maintain success without such devices, have made a highly popular record almost invisible in the hope that frustrated record buyers will unthinkingly hand over their cash for the next recording.
"This and many other cynical decisions have made the UK Top Forty little more than a guide to the most successful record company marketing departments, most of whom record singles as nothing more than trailers for albums."
Manipulation - or Just Good Marketing?
Spice Girls: `Goodbye'
The likely Christmas number one. `Goodbye' hasn't been released yet, but was `released' to Radio One some weeks ago, so listeners, and record buyers, will know it well
Boyzone: `Love The Way You Love Me'
Number two. Record company assured it a clear run, Lord Lloyd-Webber says, by cutting the previous single's price to make it ineligible for the chart.
Blur: `Country House'
The single that gave them a number one in their battle with Oasiswas an example of a `two for one' offer. So, in this case, the the true price was half price
Barefoot Man: `Hot Panty Woman'
A fan of Radio 2 DJ Sarah Kennedy heard the US single in the Cayman Islands and sent it to her as a tribute. She played it - and it went to No 21.