One of many bad ideas perpetrated by the subjects of the classic mockumentary “This Is Spinal Tap” comes when every member of the hapless faux metal band picks up an electric bass to perform the low end-centric ode to posteriors, “Big Bottom.” That memorably ugly-sounding precedent didn’t deter the four tuba and euphonium players who make up Tubular from deciding to tackle pop song covers
with an exclusively low brass lineup. The idea was first floated when all four were students at the University of Michigan more than a decade ago, and has now come to fruition as a side project for the
musicians, who all have day jobs with orchestras up and down the East Coast. As part of this year’s Fringe Festival, they’ll make their debut in Philly, where Carol Jantsch has been principal tuba of the
Philadelphia Orchestra since 2006. Jantsch discussed the project over the phone from Houston, where she was busy working on a Michael Jackson medley to add to the band’s repertoire, which already includes songs by Lady Gaga, Outkast and Queen, among others.

Where did the idea for Tubular come from?
I would bet that many, if not most, classical musicians have some pipe dream in the back of their minds somewhere of being a rock star. Playing euphoniums and tubas, you don’t often get to be the star of the show, so we thought if we make our own thing than we can be the stars of our own show. But we wanted to make sure that it didn’t suck, so it took a while to get going. I don’t know how many tuba quartets you’ve heard before, but it’s a thing that is really easy to make it sound bad.

How do you find songs that work in all-tuba versions?
Part of it is a question of willpower — how bad do you want something to work? Then you just find a way. We do break it up a bit. Sometimes our faces or people’s ears need a break from the same
texture over and over, so there’s some singing, some sound effects and alternate instruments — you shouldn't be surprised to hear a recorder or a kazoo. It does sound like rumbly elephant noises after a while, so we get creative with our solutions to make stuff sound as vibrant as the originals even though it’s down two octaves.

How do Tubular shows complement your work with the orchestra?
It’s low-pressure and high-fun. But it’s similar to the movie soundtracks that we’re playing with the orchestra. We played [a livescore to] “Lord of the Rings” back in July and we get a different kind
of audience than we see at a subscription concert. I call those gateway concerts — it’s exposure for people to see that classical music can be something approachable, that it doesn’t always have to be
a heady experience.

What originally drew you to the tuba?
I knew I didn't want a “normal kid” instrument. All the other kids were playing flute and saxophone and trumpet, and I said, “What’s that big weird one? I want to do that.” When I’m walking down the street
carrying the tuba, people constantly ask, “Don’t you wish you played the piccolo?" and they think they’re very original and clever even though I’ve heard that thousands of times. Yeah, it would be a lot
less cumbersome, but there’s a uniqueness to the tuba and the tuba community. The stereotype for a tuba player is to be friendly and outgoing and generally good-natured, and I find that to be true for the bulk of us. We have a really fun community, and I like to think that our group is a good representation of that.