Instead what plays in the house is an audio clip from the HBO television Western series Deadwood. As Grant makes his way to open the door, the sound booming throughout his house is "Welcome to f*****g Deadwood," complete with old-timey, yee-ha cowboy music.
"It's taken from a scene in which [actors] Ian McShane and Timothy Olyphant are having a fight in the main street and the stagecoach comes into town with all the new ladies of the night," Grant tells me. "They're rolling about in the mud and McShane gets up and he's bleeding and he's just about to knife Olyphant and he utters those wonderful words..."
If you didn't know Grant, you might think this strange. No doubt the priest who came to visit Grant and his family to discuss his daughter's nuptials, along with members of the church parish, might have blushed had they not known about Grant's passion. Instead, when the doorbell went mid-tea-and-biscuits, the priest simply smiled, turned to Grant's wife and said: "I think someone's at your door."
To say that Grant, 63, has an interest in the Wild West is something of a gross understatement. It is, perhaps, also a cliche to say that Grant eats, sleeps and breathes all things Western, but then there are few people who take their passion to such a level that it almost consumes their identity.
Iain Grant dresses as lawman Wyatt Earp, best known as a marshal in Tombstone, Arizona, who took part in the Gunfight at the O.K. Corral. When I say "dresses", I don't mean for entertainment, special nights out or for simply re-enactment purposes (although he does do that too, competing in "fast draw" competitions with his Brocock revolver). No, I mean, Grant dresses like Wyatt Earp - day in, day out. Other than when he is dressed in full kilt regalia for his day job as a pipe major at funerals, weddings and as resident piper at the Balmoral Hotel, Grant will be dressed head-to-toe in authentic, dapper Western wear inspired by the man who has become his obsession. He might not refer to it is as such, although his wife Catherine, the "long-suffering" Mrs Grant, as he calls her, certainly does.
"She's lived with it all the years, this strange thing that I do," he says. "People say, 'Do you just get dressed up on occasion?' But I've been doing this a long, long time. I do this 24/7. And people say, 'I don't believe that,' but it's true.
"Wyatt Earp was never a cowboy. He was a lawman, gambler, entrepreneur; just a guy who struggled to get through life - but a dandy dresser. He got all the London and Paris Victorian fashions. He was one of the gentlemen."
So dressed as Earp, Grant lives his life. "People just accept it," says Grant, with a smile. This includes his grown-up daughter, who has not really known him any other way. "There are people out there who only know me as Wyatt Earp. They don't know my proper name.
"Even when I go out shopping, I'm like this, I'll wear a Stetson."
When he goes to the local health club, he signs his name 'WS Earp' and when travelling abroad, the attire remains the same.
"We're just back from Rome and I wore my Stetson and suits," he tells me. "My daughter says, 'Do you ever get bored wearing all black?' But no, I never get bored."
Today is, of course, no different to every other day. From his cultivated trademark handlebar moustache and waistcoat down to his black boots, Grant is resplendent in his sartorial Wild West glory, fully living up to his sobriquet, sitting commandingly in his armchair like he is two steps away from laying down the law like his hero. He's got a badge and everything. At points during our chat, he twirls his gun and taps his boots.
"Even the neighbours shake their heads," he says. "When the couple moved in next door the father said to his daughter - and I don't know how he used the line - but he said to her one night, 'In this house, I'm the sheriff, I make the laws.' And his wife said, 'No, no ... the sheriff lives next door," he laughs.
Grant has a sense of humour about his unconventional pastime. He regales me with tales of his time visiting Deadwood, South Dakota, and Tombstone on holiday. One time, he made a trip to the No 10 Saloon in Deadwood to see where another of his favourite Western legends, Wild Bill Hickok, was assassinated.
"So I walked in, took a seat at the bar and, out of the corner of my eye, I saw him - Wild Bill Hickok." Rather, it was a man dressed as Hickok who was later doing a re-enactment show.
"He was his double," continues Grant. "I'm looking in the mirror and he comes up behind me and says in his wonderful drawl, 'You should be in my show'. And I was in his show the next night."
Another time back in Tombstone, which is also rife with "re-enactors", one such fellow approached Grant in the famous O.K Cafe. While Grant was munching on a breakfast of hash browns, grits and streaky bacon, the dressed-up re-enactor walked over to Grant's table, recognised he was "one of the Earps" and mumbled in his twang, "I thought we got rid of you."
"I said, 'No. I'm back,'" recalls Grant with a smile. "You're actually living the lines."
Grant's entire house, in Corstorphine, was once dominated by all things Earp and Wild West-themed. Eventually, Grant's wife, a retired schoolteacher, said: "That's it, enough is enough."
His most cherished possessions, collected over many years, have now been relegated to a single glass cabinet in the hall, though he still has his "man cave" upstairs, the climb to which is decorated with the Union and Confederate flags. However, if his wife had her way, everything would be in the garage. "I've done it slowly," she smiles. "This was a museum. It's taken me years. The next thing is that," she says, pointing to the cabinet. "I'm working my way round."
Grant's "pride and joy" is a little plaque that says: "City of Tombstone, honorary citizen," presented to him by the city's mayor, Dustin Escapule, during the final night of one of his trips to the States.
"I said to him, 'You must get thousands of tourists coming through here. Why did you pick me?
"He laughed and said, 'They come in here with their T-shirts and flip-flops but you are 100%."
Grant's first trip to Tombstone was in 2001, when he and a friend - who dresses as Bat Masterson, another Wild West figure - went out for the 120th anniversary of the Gunfight at the O.K. Corral, which saw Earp and his brothers face off against the Clanton-McLaury gang in what is generally regarded as the most famous gunfight in the history of the American West.
It was a good experience, he says, but nothing much was happening to mark the anniversary. "After we left, we kept in touch with the mayor and they decided to do bigger celebrations [next time]. But on that day, we actually stood at the O.K. Corral to the minute, to the day, and we did the walk down..."
Grant talks about his passion with all the enthusiasm of a little boy. Indeed, it is in childhood that his interest has its roots.
"I was brought up in the 1950s, when Westerns and the cinema were big. I lived in a little place down in Leith which was inundated with cinemas so, on a Saturday, you went in the morning and you went in the afternoon and it was wall-to-wall Westerns. So I always had this thing for them."
Six is an impressionable age. One Saturday, his father took him to a big toy shop. "Right, son, what do you want?" his father asked.
"I said, 'Dad, I'd like that gun there,'" remembers Grant. "And we got outside and my dad picked it up and said, 'This gun is called a buntline special and this was used by the famous lawman Wyatt Earp.'
"That was the first time I'd ever heard the name Wyatt Earp."
When Grant was older, he read Earp's life story, did a bit of research,"and something clicked," he remembers.
At times, he even borders on emotional when speaking about Earp.
But he hasn't always dressed like this. Mrs Grant - who has only dressed up in Western wear occasionally - recalls that when she first met him more than four decades ago, he wore nothing but kilts. However, as he grew into his 30s, the handlebar moustache got longer and the clothes became more Western. Now, his passion infiltrates every aspect of their life. Even his personalised licence plate is E4RPW.
"We don't have the news on in our house during breakfast," she tells me "I come downstairs and Gunsmoke [the Western TV series] is on every morning."
People often suggest to Grant that he is Wyatt Earp reincarnated - but he dismisses this idea. "'You should go for regression therapy,' they say. But I say, no. I don't want to delve too deep into the thing. Something happened in my life and I don't know... people ask these questions: 'Was it a voice? A bolt of lightning?' No. I don't want to investigate. I just relate to the whole thing. I can't understand it, and maybe I don't want to understand it. It's just a weird, weird thing."
Once, during a visit to Tombstone, he found himself at the Birdcage Theatre, a veritable time capsule of the era where not much has changed since 1880. He admits the place was atmospheric, and the sight and smell of its interior left him feeling a bit strange. After all, it was a place that typified everything that "pulses through my veins," he says.
Another time, at a dance in Leith, Grant met an amateur medium who was picking up on a vibe from him. "All of a sudden the guy was speaking with another voice. A lot of the things he was saying where quite relevant to the West, to Doc Holliday..." - Wyatt Earp's real life best friend and fellow shooter at the O.K Corral - "He was saying things that just an ordinary guy wouldn't know..."
When Grant decided to get dogs he ended up with 11 Siberian huskies in his back garden. It was only later he realised that Wyatt Earp once lived in Alaska and also owned Siberian huskies. Incidents like this puzzle Grant but he writes them off as coincidence.
Has he always been so passionate about what he does? "I never get bored with it, never tire reading about it and watching it. But, no, it's something that has never disappeared. It's always been there and this is the way I will go about every day."
Nor is he put off by people asking for their picture with him - which happens.
There's one place, though, he's never been to see - the grave of Wyatt Earp.
"I'm amazed you've never wanted to see it," remarks his wife.
"That's the next trip," smiles Grant. n