"Their albums and ours [Bajofondo's eponymous debut] came out within the space of three months," says Santaolalla. "We were both working on these projects, without each knowing about the existence of the other. The idea was in the air. Now there's a lot of projects doing fusion, but the difference is in the results. After the experimentation, it's very different."
Superficially, the Gotan Project and Bajofondo Tango Club might be seen as covering similar territory, combining Buenos Aires tradition with electronica and DJ techniques. Bajofondo's Womad set revealed a more earthy approach, though, with the laptop beats and scratching input taking on a heightened level of aggression, even compared with their album incarnations. Even so, for such predominantly young players, there is still a remarkable sensitivity to the sepia traditions of the Twenties, and the swerving dynamism of the South American brothel dancefloor.
The name Bajofondo refers to a seedy underworld where the tango form remains intact, but the band's music has an electronic feel, and includes some complex beat-programming. The violin and bandoneon solos are as convoluted as they would be in the old days, but negotiating a new terrain of bumping basslines and buffeting samples. The live visuals add to the historical ambience, jump-cutting images of black-and-white days, updated by the quick-fire juddering of edits.
"We feel that the Gotan Project is a more European version." Santaolalla continues with his comparison. "There's only really one South American member. So we feel that our results are very different, that our music has a different vibe. We are really not comfortable with the concept of electronic tango - we feel that what we do is more contemporary music. Tango is there because it's part of the genetic musical map, but also in our history rock and hip-hop also play an important role. To make an analogy, it's also like soccer. We're playing South American soccer. There's a different feel..."
This is so, but it is puzzling why Santaolalla would seek to deny the "tango electronica" tag when a majority of listeners would surely agree that this is an apt description. The argument lies in the depth of the marriage.
Santaolalla is no fresh face. In the Seventies, he led an alternative rock band, Arco Iris. "When I was 16, I had the same kind of vision, and that was very criticised by the rock intelligensia, but I always wanted to do music that had identity, that was concerned with who we were and where we came from."
He developed a sideline of producing a large alternative-Latin-rock roster. "All those acts have something in common, that identity. Tango was always something that was waiting for me, and now it's my time to do this. We didn't want to just throw down a drum loop with some minor chords, and then put a bandoneon on top. We wanted to find a language. Everything is possible. We might sample some old vignette of something that will inspire, or maybe Juan [Campodonico] comes up with a groove. There's not one single way of doing it."
So this is where Santaolalla is discovering his new persona, taking a step back in time, to 50 years before rock'n'roll. I quiz him about the genesis of the Bajofondo collective, and when he started working with Campodonico, who comes from Uruguay.
He says he was producing an album for Campodonico. "I really liked what he was doing. So when I dreamed about this concept, he was the first person I thought of, and he knew the pianist Luciano Supervielle. Bajofondo is a collective project that started close to four years ago, with experimentation that translated into what became the first album, which was more of a 'lab' type of record.
"Juan and myself worked together to design this new language that we were looking for. We invited a whole bunch of friends, and even some other producers, to bring everything to be filtered by us, but when we came to the situation of presenting the record live, we had that challenge ourselves.
"After the first two members, Luciano Supervielle and the violinist Javier Casalla, we took a while to get the bass player. Now we've been with this outfit for two and a half years, playing all around the world. It's really more like a band, and we are now working on a record as a band."
Bajofondo appear to be forming an umbrella-identity in a similar fashion to that adopted by Buena Vista Social Club. Santaolalla's own label, Surco, has a deal with Universal in the States, and the concept is to present solo projects by individual members of the collective. The most recent Bajofondo disc is by Supervielle, who's just using his last name on the cover. Most of the live Bajofondo crew were involved in the sessions.
"His record has a more personal view," says Santaolalla. "We work together to reinforce a particular view of one of our members. The Bajofondo aesthetics are there. It's a different way of designing a working group. We have certain lines of procedure. We almost never rehearse, because we don't have that physical reality."
'Bajofondo Tango Club Presents Supervielle' is on Surco Records/Universal