Since Rob Brydon gave up voiceovers for comedy, he's used his distinctive Welsh baritone to build a range of comic characters. Now, he tells Michael Rosser, he's speaking up for new talent with the launch of indie Arbie.

A conversation with Rob Brydon is an inadvertent masterclass in comedy. Belting out his rendition of Islands in the Stream - a seminal moment in hit BBC comedy Gavin & Stacey - he explains the importance of singing every word in a heavy Welsh accent. Rolling out his uncanny impressions of Ronnie Corbett or Michael Caine, he is quick to point out how their voices have changed over the years. Recreating entire scenes from award-winning series Human Remains, Brydon gleefully breaks down the scene line by line to highlight the nuances of the script.

The 43-year-old Swansea-born actor, writer and producer is a far cry from the naive, old-fashioned Uncle Bryn that he plays in Gavin & Stacey, the nasty version of himself in panel-show parody Annually Retentive or Keith Barret, the tragi-comic creation that -provided his breakthrough in the acclaimed one-man comedy series Marion and Geoff.

Brydon is serious about comedy and is using his clout in the industry to usher in a new wave of talent. He is doing this with Arbie, an indie he has launched with executive producer Miles Ross - brother of Jonathan Ross - and which is backed by Talkback Thames.

Talkback has taken a stake of less than 25% in the company to ensure it retains indie status. Talkback chief executive Lorraine Heggessey, with whom Brydon has always had “an above-average rapport”, will sit on Arbie's board alongside chief operating officer Sara Geater.

Smartly dressed and exuding -confidence, Brydon leans forward and lays out answers in his distinctive Welsh baritone. His message is simple: he wants to help develop talented people who deserve the success he now enjoys.

“There are friends of mine who are writers and performers who I feel ought to be doing more and I'm trying to find the right thing for them,” he says.

“For me, the right thing didn't come along until Marion & Geoff. I'm trying to find their Marion & Geoff that will have their voice as well as integrity.”

Brydon's “right thing” was Keith Barret, the show's wildly optimistic minicab driver and estranged father who delivers monologues while waiting to see his two sons - “My little smashers”. He is keen to correct those who believe the character is autobiographical, since Brydon is himself divorced with three children from his first marriage (he is now married to a former South Bank Show researcher).

“When creating characters, you're expressing parts of yourself, sometimes more than you'd like to admit and sometimes far less than people think. The obvious example is Marion & Geoff because [weary sigh] I'm divorced and he's divorced, but that's not the case. There are far more of my traits in the six characters I played in Human Remains.”

A teaser tape of the lonely, comedic Barret - created with old drama school friend Hugo Blick - brought him to the attention of Steve Coogan, who was enjoying success with his own comic creation Alan Partridge back in 2000.

“I had a great start in that [Coogan's indie] Baby Cow was my first experience of an independent production company,” recalls Brydon. “I was very impressed by the way they nurtured talent. Even now, they find talented people and let them do their thing. I was lucky to fall in with them.”

At the age of 35, Brydon left behind a£200,000-a-year career recording voiceovers for the likes of Toilet Duck and Sudafed - with a sideline in presenting for the Shopping Channel - to pursue his long-held acting ambitions.

“What Steve did for me is say ‘I'm right behind this guy' and the BBC listened to him because of who he is. Hopefully, the same will apply for us.”

Now it's Brydon's turn to use his contacts and reputation to get Arbie's first trio of shows off the ground. The first is Lifespam, a half-hour spoof shock doc that is being made for BBC3.

“That's being written by Alice Lowe, who I met on Annually Retentive,” says Brydon. “Alice played one of the writers and always stood out with a very offbeat sense of humour. She has her own kind of vision.”

The second is Freddi, created by newcomer Sasha Alexander, which broaches the topical subject of Russian oligarchs in London. “It's a lovely combination of comedy and drama,” says Brydon, who will feature in a small role.

“It's something I could go to the BBC with full of enthusiasm because I believed in it 110% and banged the drum.” Brydon was script editor on the project and has secured a commission from BBC4 for a pilot.

Then there's Candy Chops, the story of fictional aspiring rap artist Ethx. It has been written by Kelly Marcel and Tom Hardy, recognisable from his roles in Stuart: A Life Backwards and Guy Ritchie movie RocknRolla. “Tom is an extraordinary talent and an impressive individual,” Brydon enthuses.

He is keen to shine a light on the challenges faced by talent at a time when audience figures are dwindling. “It's never been easier to get on television and it's never been harder to get viewers,” he observes. “Even on YouTube, you're kind of on telly. But the lines between TV and online content are getting more blurred so it's never been harder to get a substantial amount of people to watch your work.”

In many ways the world of comedy has changed because the way that it is consumed has transformed, he contends. “In the past you would give something a certain feel, based on the knowledge that it would be watched at 10pm on BBC2. Now, there's every chance a large percentage won't watch at that time and will instead view it on their iPod the next morning on the way to work.”

While having to shoulder the responsibility of a new company, Brydon is arguably enjoying more success than ever as a performer, most notably as the excitable Uncle Bryn in Gavin & Stacey. The accessible but edgy sitcom, produced by Baby Cow, has experienced a meteoric rise from its beginnings on BBC3 to multiple Bafta wins, a commission for a Christmas special on BBC1 and an open invitation for a third series. “I've read it and it's very funny,” says Brydon of the festive episode, which will be filmed in October.

The role surrounds Brydon with old friends and collaborators, including Julia Davis, whom he met at an improv group in Bath in the early 1990s and starred alongside in Human Remains 10 years later. It also includes the show's co-writer James Corden, who played his son in comedy drama Cruise of the Gods in 2002.

But his most long-standing friendship is with Ruth Jones, who plays worldly-wise Nessa and co-wrote the series with Corden. “We were at Porthcawl Comprehensive School together and starred in musicals such as Carousel and Guys and Dolls,” recalls Brydon with a smile. “We attended the same improv group in Bath and would drive from Wales singing the harmonies to Barbara Streisand songs. So when we ended up singing together in Gavin and Stacey, it felt great.”

Their rendition of Islands in the Stream looks set to be recorded for release at Christmas, but Brydon remains tight-lipped on the subject along with the prospect of a third series. “I know the BBC wants it but it's up to James and Ruth. It's very much their baby.”

He is also preparing to revisit the documentary genre, following a popular outing with BBC4's Rob Brydon's Identity Crisis in which the actor regained his love of his Welsh identity or “hiraeth” - having lampooned national stereotypes in his stand-up routines for years. “BBC4 has asked me to make more so it's a question of finding the right subject matter.”

Brydon is also keen to stretch his dramatic muscles again, having made forays into more serious roles in Oliver Twist and Napoleon for BBC1 as well as in the title role of Kenneth Tynan: In Praise of Hardcore for BBC4. But attractive roles are rare.

“I don't do as much stuff on the telly as I might because I have high standards,” he says. “I look back on most of the work I've done and it's of good quality, particularly of late. I want to keep that level up and turn a lot down.”

He often knocks back small parts in big films because he “just can't be arsed”. The last film he appeared in was the critically lauded A Cock and Bull Story, directed by Michael Winterbottom and co-starring Coogan. “I don't want to make movies just to say I'm in films,” he says. “It's boring. I prefer being in something like Gavin & Stacey where I know everyone.”

Coming up, there will be projects with Arbie in which he makes a star turn and Brydon is quietly building a compendium of characters that may populate a new sketch series. “I sometimes toy with the idea of a sketch show because I have some characters, like an American who works in a British police station but who acts like Al Pacino.” He bangs the table, transforming himself into the grizzled Hollywood actor with a shout of “What have you got?”.

The immediate future will see Brydon return to stand-up, and a tour of Wales begins in November. “Comedy is perhaps the most subjective of all forms of creativity because of the response it elicits,” he declares. “It has an almost drug-like response in that it elicits laughter - and laughter is something we value so very highly.”

Rob Brydon will be speaking at the TV Comedy Forum on 18 September