A collection of every UK number one single since the chart began has failed to sell at auction in London.
Elvis Presley holds the record for the most UK number one singles
Bidding reached £22,000 - falling short of the £25,000 reserve price at the sale at Abbey Road Studios.
But the auctioneers remain hopeful of negotiating a private sale outside the auction room.
The 2,139 items - including seven-inch and 12-inch vinyl singles, cassettes, CDs and MP3s - are owned by Stephen Hitchcock, 35, from Brighton.
Before Friday's auction, he said: "I would love whoever buys it to continue the collection, or even better I would love it to go into a museum."
He has been adding to his singles collection since inheriting it from his father and grandfather 23 years ago.
"I started buying first edition number ones every week and then, over the next 10 years, updated the collection," he said.
Mr Hitchcock's grandfather bought the first ever number one single, Al Martino's Here In My Heart, in November 1952.
The collection comes in professional DJ storage boxes.
The 78rpm records can be listened to on an original Pye Black Box from 1955, while the digital downloads come with an iPod Nano to play them on.
The first number one to be included as a download was Tony Christie's Amarillo from March 2005.
John Collins of auctioneers Cooper Owen said: "This is probably the biggest collection of British popular music ever discovered.
"I've never seen anything as extensive... with so many rare pieces."
The sale coincides with the 50th anniversary of the UK album chart on Friday.
UKALBUM CHART ANNIVERSARY
First number one - Frank Sinatra, Songs for Swingin' Lovers
Most weeks at number one - South Pacific soundtrack
Fastest-selling album - Oasis, Be Here Now
Artist with most number ones - the Beatles (15)
Best-selling album of all time - The Beatles, Sgt Pepper's Lonely Heart's Club Band
Source: Official UK Charts Company
The event is being celebrated with a national public vote to find the best album of the last five decades, with the results to be published at the end of August.
A chart fans' convention will also take place in London in August.
Frank Sinatra's Songs for Swingin' Lovers was the first UK number one album on 28 July 1956.
Since then, The Beatles' Sgt Pepper's Lonely Heart's Club Band, released in 1967, has sold more albums than any other in the UK.
And the record for the most weeks at number one is held by the South Pacific soundtrack, which has spent 115 non-consecutive weeks at the top.