Take the story of his first day on The Scotsman. It's said that he burst into the offices declaring: "Where are the girls? I'll lay them like tables." An awe-inspiring thought, albeit apocryphal. "I wish I'd said that," he lamented to one recent interviewer.
While he will probably be remembered for coining one of British TV's most memorable catch-phrases, dour quiz master is but one of many roles Magnusson has played. The print journalist turned broadcaster is a literary, historical and archaeological scholar, a self-confessed linguistic pedant, the author of numerous books and an ardent bird-watcher.
He's even found time to chair the Scottish National Heritage Agency, securing himself an honorary knighthood - although as an Icelander, he can't be called "Sir".
A hard act to follow, then. Unless you're a Magnusson. Undaunted by their father's achievements, each of his four children has pursued a career in broadcasting.
It all began in 1929 when Magnus was born to Icelandic parents. When he was nine months old they moved to Scotland, following the appointment of Magnusson Senior as European manager of the Icelandic Co-op.
By all accounts, they were an academic, upwardly mobile family; his father was later to become a consul-general. Young Magnus won a scholarship in English to Jesus College, Oxford. (His son Jon - pronounced "Yone" - would later do the same.)
Magnus began in print journalism, working as assistant editor on The Scotsman and the Scottish Daily Express, where he met his wife, the star columnist Mamie Baird. When opportunity knocked he moved into TV, notching up credits from programmes such as Tonight, Pebble Mill at One and Chronicle.
The Magnussons are frequently described as a close-knit clan; Magnus's children speak of warm encouragement from their dad.
Eldest daughter Sally, 41, joined Thomson Regional Newspapers after a first-class honours degree in English at Edinburgh University. She worked as a reporter on The Scotsman, then joined the ill-fated Sunday Standard in Glasgow. She then moved into TV, presenting Sixty Minutes, London Plus and Breakfast Time, working alongside Jeremy Paxman and Nicholas Witchell. She married the director Norman Stone, whose latest credit is the ITV drama Ain't Misbehavin', and is now working on Breakfast News.
Margaret, 38, joined TV-am after Oxford University. She worked as a producer on Newsnight, and is now chief assistant to Paul Hamann, BBC TV's head of documentaries. Her husband is the producer/director John Paul Davidson.
Meanwhile, Anna, 37, entered broadcasting after writing books and working as a free-lance journalist. Today she produces documentaries for BBC Radio Scotland, based in Glasgow.
The one non-journalist is Jon, 32. After Oxford he worked as a jazz pianist. In 1989 he joined Radio 4 and ended up in light entertainment, nurturing talent such as Harry Hill, Nick Revell and Struck Off and Die. He went bi-media, producing Alas Smith & Jones for BBC TV, then left the corporation in 1995 to free-lance. He has since produced a number of projects through Mel and Griff's production company, Talkback.
Growing up in a media family undoubtedly helped, he says. "Not because of nepotism, but because, like most children of a family in business, you grow up having no fear of the trade." Which augurs well for the careers of a growing number of mini-Magnussons