There was a band playing in the family's back garden most nights. These weren't parties, but a rare example of Johns' father, Glyn, bringing his work home with him.
"My bedroom window looked out onto the garden and I can remember staying up, watching what was going on," he says. "Dad was running cables to a mobile recording truck and I was fascinated. I'd have been seven and it was the first time I was able to work out what he did for a living. Yeah, Dad makes records."
Dad has indeed made records: Bob Dylan, the Beatles, the Who, the Rolling Stones, the Eagles and a list as long as Goliath's arm have all called on Glyn Johns's engineering and/or production skills. And these skills have been passed on as Ethan became first his father's apprentice and then the go-to guy for record production that captures the natural sound of the musicians in the room they're recording in.
You can call Johns old-school he won't mind. It's the reason Sir Tom Jones chose him to produce his career-resuscitating Praise & Blame album and its follow-up Spirit In The Room. To Jones's name you can also add a studio list that's in danger of catching up with his father's and includes Paul McCartney, Paolo Nutini, Rufus Wainwright, Laura Marling and Ray Lamontagne. He's also played on records by John Hiatt, Emmylou Harris and Crosby Stills & Nash.
"Music has always been a big thing in my life," he says. "My earliest memories are all related to music, like that recording session in the garden. Buckacre, the band was called. Glyn also recorded the Ozark Mountain Daredevils, a great band with great songs and great harmonies, in a garden, but it was their garden in the Ozarks, not ours. It was probably around that time, maybe before, when I picked up an Appalachian dulcimer that was lying around the house and was mesmerised. There were always instruments around so I'd pick them up and off I'd go."
By the age of 10, he was hanging around the studio his father had subsequently built in the garden and he remembers sessions by the Who and the Clash. Their house, he says, was not a rock 'n' roll house or party central but his father's musician friends would call round and Kenney Jones of the Who, Bernie Leadon of the Eagles and Andy Fairweather Low became friends and mentors to the young Ethan.
"I never had a career plan, I just played in bands - at school I played with the staff jazz band for a while and if ever there were musicals on the go, I'd be in the band," he says. "But I did become my Dad's apprentice. You might as well learn from the best and it was a great grounding in the art of recording. I kept playing in bands and doing engineering work and I kind of became a producer by accident. I'd be hanging with musicians and I'd work on their demos then someone would get a deal because the record company liked the sound of the demo and I'd get asked to do the record. It sounds haphazard, and it was. I've just gone with the flow."
While working on other people's music, whether in the studio or as a touring guitarist, drummer and keyboards player, Johns was also working on songs of his own. His father played one of his demos to John Hiatt and Hiatt's response was that the songs weren't up to much but they should get the drummer into the studio to work on the album they were recording at the time. Ethan had played all the instruments on the demo, so the drum stool was his for Hiatt's album.
"Music's a non-stop learning process," says Johns. "You learn from everyone. I've produced people who have been making records for 40 or 50 years and you can't help but learn from them. At the same time, they may be icons but as far as recording's concerned, for me, everyone's the same. We're all there to achieve the same result: make the best record we can make."
One of Johns's first production assignments was alt-country singer-songwriter Ryan Adams, and having eventually released his own debut album at the age of 41, If Not Now Then When in 2012, when he was ready to make the follow-up, The Reckoning, he turned the tables on Adams and asked him to produce.
"I learned a long time ago that you can't produce yourself," he says. "You can't judge your own performance because you don't have the perspective - the distance - that you need. Ryan's a great producer. He's a real force to be reckoned with. He doesn't compromise and the way he responds in the studio has been invaluable to me."
The Reckoning is due for release early next month, but Johns already has the songs written for its successor. After years of helping other people's careers he's now concentrating on his own. His studio assignments aren't likely to dry up yet though.
"The music's flowing and I'm really enjoying it," he says. "Of course, I'll never be the guitarist I want to be because Ry Cooder, Bert Jansch, Richard Thompson and loads of others got there first. But I have a simple goal: do what you love and do it better this time."
Ethan Johns plays Deeside Inn, Ballater, tonight; Ironworks, Inverness, tomorrow; Woodlands Centre, Stornoway, on Friday; Ceilidh Place, Ullapool, on Saturday; An Tobar, Tobermory, Tuesday 20; Voodoo Rooms, Edinburgh, Thursday 22