Peter Infeld Upright Bass Strings

Thomastik worked on these strings feverishly for well over a year, and now they have finally brought them to you! Officially launched at the ISB conference in Tallahassee in 2025, these new strings promise to bring a whole different vibe to the Thomastik lineup of strings. They were reportedly a big hit at the convention, and we are looking forward to getting acquainted with them very soon.

In the meantime, here's what Thomastik is saying about them:

The strings’ tonal core is centered and well-balanced and their sound is powerful in the mid frequencies. They offer a substantial amount of sound colors, but leave you as a player in control at all times.

But here’s what makes our PETER INFELD ® strings particularly popular with so many players and their audiences: We developed them to produce a special bow noise that contributes to a remarkable projection, which makes your sound shine all the way to the farthest corner of the room.

From what I've read, they use a similar core to the one in the venerable Spirocores - but provide a bit more damping to get a warmer, less mid-rangey response for both arco and pizz. Some players who tried the prototypes are saying that they're more suited for arco, others find them to be great for jazz. Many are saying that they fall, tonally, between the Spiros and Belcantos.

We'll have more information when we've had a chance to put them through their paces.

Tension and Gauge:

Usable on basses from 103cm (40.6") to 110 cm (43.3")