Earlier this year, Spinal Tap’s three original members (Christopher Guest, Michael McKean and Harry Shearer) appeared at the Ohio Theatre just to prove they’re still funny after all these years. Calling the show “Unwigged and Unplugged,” they revisited many of the best-known Spinal Tap tunes, including “Stonehenge,” “Bitch School” and “Hell Hole.” But the unplugged format also let them perform “Corn Wine,” “Old Joe’s Place” and “Loco Man,” all of which are by the Folksmen, the fictitious group the actors portrayed in the 2003 movie A Mighty Wind. A much different beast than Spinal Tap, “Unwigged and Unplugged” allowed the guys to include music from their entire repertoire (including tunes by the Thamesmen, the fake classic-rock act that preceded Spinal Tap). Stripped-down versions of Tap tunes such as “Big Bottom” and “The Majesty of Rock” sounded fine without all the heavy-metal bombast. A DVD of a concert from that tour has just been released, and Harry Shearer phoned in to talk about it. Here’s what he had to say.

What is more difficult? Performing as Spinal Tap or performing as yourselves?
Well, probably when we started out, performing Spinal Tap was more difficult. But performing as ourselves was a new first. It was more challenging in terms of how to perform the songs and what choices to make musically.

How difficult was it to adapt the Spinal Tap songs to an “unplugged” format?
Well, it depended on the song. Some of them we threw out. Obviously, the Folksmen songs were easier to adapt. Some we ended up doing roughly the same way, like “Heavy Duty.” And some we did drastically differently, like “Big Bottom.” We spent six weeks rehearsing.

What made you want to do the tour? Was it the 25th anniversary of Spinal Tap?
It was the anniversary. It was the fact that we wanted to do something different. We had done this once or twice in isolated circumstances and always had a good time.

The DVD captures a show at the Riverside Theatre in Milwaukee. Was this the best show of the tour?
It was the very last show on the show. I think it was in fact one of the best. I think we had it down by that point.

I half-expected to see some bonus footage of you guys in your Spinal Tap outfits. Was that ever discussed?
The director said he wanted to shoot us backstage or on the bus. And we said, “No. We make fun of that stuff. We don’t do it for real.” My focus was just to get a really good document of the show itself. There’s plenty of other places where you can get us acting like Spinal Tap. This was a unique event and I wanted to present it as such.

Will that Wembley Spinal Tap show end up on DVD?
I don’t know. I don’t know if it was shot. I heard there was a camera crew there but I have yet to see any of their footage. I don’t really know.

During the show, you talk about that very first performance on The T.V. Show. Did you have any sense back then that Spinal Tap would become what it became?
Oh God, no. We were just having a good time and trying to do something that made us laugh. Nobody sane sets out to do something they know will be watched in 25 years. There’s no way to know if that will happen.

What’s made Tap endure?
We weren’t making stuff up. We were basing it on what we knew about the world of music and this kind of music on tour, either from our experience or from the experience of other people. It rings true. Bands take that DVD on the bus with them because it makes fun of the life they’re actually living. Because of our low budget, we couldn’t fill the screen with artifacts of the moment to prove how real it was. We couldn’t have TVs and phones and cars everywhere. Those are the things that look dated the most quickly. As a result, you don’t have all these things that scream 1984 at you.

You have a question and answer segment during the show. Do you ever get stumped?No. One way or another we always come up with something. That’s the advantage of having three people on stage.

There’s a guy from Ohio who performs in Air Guitar competitions as Derek Not-So-Smalls. Have you ever met him?
No. But of course, he should be playing air bass. That would be my advice to him.