After decades of dodgy American accents on our pop airwaves, at long last comes a genuine Yankee DJ. Perhaps the flat tones of Karl Tsigdinos on Shakin' Street (Radio Ireland, Monday to Friday) lack something in the way of charisma, but the man has other qualities. Some listeners might even say that a love and knowledge of music, plus an ability to weave songs together into an engaging tapestry, would be useful attributes for other Irish presenters.

Tsigdinos is, of course, a mere "summer" substitute in the midmorning slot recently abandoned by Cliona Ni Bhuachalla. Come September, we can expect something entirely new and different - like maybe an opinionated writer with right wing views - bad hair might be an asset, too - from the Sunday Independent. It's worked in the evening, hasn't it?

Praise for Tsigdinos in this column is nothing new. His River of Soul has long locked me into Radio Ireland on a Sunday morning, and he was previously a highlight on Anna Livia FM. The tunes on Shakin' Street are, well, whiter than most of what we've heard him play before, but he mixes some soul and R&B with the pop chestnuts that fill the programme.

Let's get hyperbolic: this is, arguably, the best pop-music show ever to occupy a regular daytime slot on a national station (no, the competition is not fierce, sure it's not?). Much of what Tsigdinos plays is "oldies", but without the imposition of a corporate notion of musical "memories" that makes the Classic Hits format sofascist. In the idiosyncratic real world of Shakin' Street, your memories of, say, the late 1970s can be of Dave Edmunds and the Undertones rather than of Phil Collins and Fleetwood Mac.

Other individual touches, like a pricelessly touching old tape of Otis Redding singing an anti-drugs public-service message, make Shakin' Street more than aural wallpaper. This was the musical promise of Radio Ireland when it was launched; let's hope some semblance of it survives the autumn shakin'-up.

Indeed, it's a bit late to advise it now, but yesterday - with Tsigdinos in the morning and John Kelly and Donal Dineen teaming up for eight hours from 5 p.m., plus the perfectly acceptable Philip Cawley in between - was a Bank Holiday to move the barbeque inside near the stereo and crank up Radio Ireland.

You would have got special dispensation in the early afternoon to switch to RTE Radio 1 for The Supremes: Divas of Motown, the latest in Colm Keane's amazing series of pop interviews and biographies. Strangely, however, this episode didn't display the relish for the long descent down the "rock 'n' roll rollercoaster" - as Keane likes to call it - that usually characterises his programmes.

Partly that's because of the interview options. Of the original Supremes, Florence Ballard is 20 years dead, and the active ego of Diana Ross would hardly slow down to speak to Irish radio. So the programme was based on a chat with Mary Wilson, whose comments were occasionally sharp - about her Motown contract, certainly - but didn't dish much dirt.

Referring to Ross as "Diane" was about as nasty as she got about her unequal ex-partner. And Keane seems to have elicited no comment from Wilson about how the talented drink-and-diet-pill-swilling Ballard was ejected from the postDiana Supremes shortly before her death.

Her best yarn was about the time in 1965 when the publicists arranged for the Supremes to meet "the other supergroup" in a New York hotel: the appearance-conscious women were too prim 'n proper, it seems, for the Beatles. "They were rock 'n' rollers, and all the people around them were rock 'n' roll people."

She later learned from George Harrison that the Liverpool lads had expected a groovin' party with three black girls from Detroit, not tea and biscuits with the heavily made-up and well-mannered young ladies they met. The Supremes, meanwhile, thought the Beatles smelled funny, and both PR teams were asked to bring the get-together to a rapid conclusion.

Wilson is rightly proud of the Supremes' role in bringing the world an image of black women as something other than "whores, housewives or domestic servants", but she didn't seem to wonder why that image had to be the particularly prettified, slightly insipid one her group offered - after all, the Chirelles, she admitted, were better singers, and Martha and the Vandellas more soulful.

Colm Keane's production didn't probe any further, with snippets from the group's hits, rather than - for example - bits of their prestardom background singing with Mary Wells or Marvin Gaye. We'll just have to rely on Karl Tsigdinos for that.

Changes are afoot in BBC Radio 4, and apparently in the beloved Radio 3 as well, with rumours of the latter moving toward more familiar "classics". Both stations have many loyal listeners in Ireland; I, however, am in the "occasional" category the Beeb are trying to lure in for longer.

I'd be delighted to hear from readers whose listening habits will be more profoundly affected by the changes, with a view to publishing some of your views in this space.