As the late Ronnie Scott used to say, it's easy enough to make a million pounds running a jazz club. You just start with two million. It was one of his favourite jokes, and he must have told it a thousand times at the club in Frith Street, Soho, he founded 50 years ago this year. But it contained a kernel of bitter truth.

In its 46 years under Mr Scott's ownership and, after his death aged 69 in 1996, that of his friend Pete King, the club lurched from one financial crisis to another. Such was Mr Scott's standing in the jazz community worldwide that he was able to persuade first-class musicians to appear on Frith Street for rather less than they would charge elsewhere. But the club was tatty and run down, a great part of its charm but not ideal for a professional venue.

In 2005 the club was sold by Mr King to theatrical impresario Sally Greene. She undertook a complete refurbishment, and Ronnie Scott's reopened in June 2006.

For those who remember it in its scruffy heyday, it is a transformation. With banks of smart benches either side of the room - actually the original ones, taken out and remade - discreet lamps and plush red decor, it resembles an oversized Pullman luxury railway carriage. Upstairs is Ronnie's Bar, a smaller, cheaper venue designed to attract a younger crowd, where local musicians are encouraged to sit in on jam sessions.

One of the first things Ms Greene did was to bring in a music industry veteran as managing director charged with finding new outlets for the greatest brand in European jazz. Simon Cooke had done a similar job elsewhere at the radio station JazzFM, where he was enterprise director. He started the station's record label and then several others, including Hed Kandi, the dance label, later sold to the Ministry of Sound. He started putting on gigs, often for advertisers.

There are strong parallels between JazzFM and Ronnie Scott's. Both have had to walk a difficult line between more profitable populism and placating the tooth-grinding purists. The station had for a while even dropped the “J” word entirely, operating as Jfm and playing soft soul and rock, the likes of Simply Red and Chris Rea.

Mr Cooke was brought in by Richard Wheatley, the former ad man who arrived as chairman in 1995, restored the “J” word and “took all the Mick Hucknall off the playlist”, he says. But the station was always going to have difficulty surviving in the commercial arena. It had an extravagant head office in a mews off the Edgware Road, and all the expenses and disadvantages of a small quoted company - “the tyranny of the analysts”, as he describes it.

His division eventually provided three fifths of all revenues and “created enough profit that we were able to stabilise the cashflow. We made pots of money and the radio station didn't”. But in 2002 Guardian Media Group and two other big shareholders launched an unwanted bid. Mr Wheatley and the rest of the board managed to push the offer higher - “The Guardian didn't want too much of a public row” - but the bid finally succeeded and most of the board departed.

He stayed for a while. “It wasn't really my habitat, a big corporate culture. You got pushed around a bit.” In the end, JazzFM became SmoothFM, with all that implied for its output, “which was a bit of a black day for British jazz. They came down to London. They bought JazzFM and they shut it down.” Mr Cooke left and rejoined Mr Wheatley in a local radio venture which floated on the stock market, but his heart wasn't in it.

He spent around a year doing nothing much before taking a call from the marketing director of Comic Relief, an old friend, joining on a short-term contract to work on Sport Relief. It was a strikingly non-corporate culture. He was used to businesses talking in terms of corporate objectives “like 5 per cent growth, greater returns to shareholders, improving the product”.

Then came the call from Ronnie Scott's, two years after the reopening. I ask if it was staying true to the spirit of the place, spending so much to make it so comfortable - Ms Greene has never said what she paid Mr King, but it is likely to have cost her several millions, and the refurbishment the same again.

“It depends what kind of jazz club you want to run. You can run something really grotty. But it's an expensive building, a significant piece of real estate in the middle of Soho and we pay rent on it. Is that what Ronnie's had got to be, because it got into that state over 40 years?”

The main room at Ronnie Scott's seats 220 people, though the restaurant runs out of steam if more than 180 are eating. The Bar upstairs can accommodate 120 comfortably. There are three revenue streams, ticket sales - contrary to popular belief, it is not a members-only club and you can walk in off the street if there are seats spare - food and drink. In such a small venue, income from tickets can easily be swallowed up by the musicians' fees.

An offshoot of the club in Birmingham ran before Mr Cooke's time for eight years but never took off. He does not believe that there is scope to open in another British city but is prepared to contemplate an overseas club if the right partner can be found. Prospects are good for replicating the Bar, with its younger clientele and cheaper entry fee, elsewhere in the UK.

He has ambitious plans, about to be tested, to make performances at the club available on the internet. “What I want to do is create an online membership where you can go and see audio-visuals of the club. If you're in Japan, you will be able to see a concert two hours after the show.”

The club had operated a small record label, mainly of live performances. Mr Cooke is not keen to revive this. “Everybody expects me to start this whizz-bang record label. I'm taking my time,” he says. “The record business is on its knees.” Margins, especially for jazz musicians, are negligible. “Maybe you put out a live album selling 500 copies and make a grand. It's a lot of work to make a grand.”

Other prospects include raising the profile of the in-house Ronnie Scott's Allstars quintet and Ronnie Scott's Jazz Orchestra, and a radio show from the club, with interviews and performances, that could be sold in Europe.

Is the club profitable in its new form? “It's heading towards profitability.” The house was packed from mid-October to the end of the year, and membership, offering discounts and first call on popular tickets, is up 40percent over the past two months.

There is still that tension between authenticity and profitability, though. After the reopening, the booking policy veered towards the popular, he admits. Mr Cooke has been encouraging back some musicians who had been a staple under Mr Scott and Mr King, such as Airto Moreira, the Brazilian percussionist, and Roy Ayers, the vibraphone player, who played lengthy residences back then but had slipped away.

The club still hires straight jazz artists such as Abdullah Ibrahim, the South African-born pianist, and, separately later this year, Branford Marsalis, Joe Lovano and Joshua Redman, the American saxophonists. But late 2007 saw a rare appearance from Jeff Beck, the rock guitarist, Phil Manzanera, the former Roxy Music member, is appearing shortly, and Mr Cooke mourns a lost opportunity to sign Chuck Berry.

What would Ronnie himself make of all this unbridled commerciality, in the club's 50th year? “I think he would probably accept that the club being a bit smarter, a bit more expensive, was a necessity. Where Ronnie sits on your shoulder is musically. We keep what we do as jazz as possible.”

CV

Born September 15, 1958, Leeds
1974 Westminster Hotel School
1978 Night manager, The Venue, Victoria
1981 Working on the merchandise crew, Genesis, and other rock artists
1983 Founded Firstflame, to represent US merchandising company in Europe
1990 Started work freelance for JazzFM, running concerts, events
1996 Joined JazzFM
2002 JazzFM bought by Guardian Media Group
2003 Left JazzFM
2004 Founder director, The Local Radio Company
2007 Contract at Sport Relief
2008 to present Managing director, Ronnie Scott's Club
Family Married, two daughters

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