Slovakian ‘national paywall’ startup Piano Media has raised €2m ($2.6m USD) in a Series B investment from 3TS Capital Partners, as it aims to expand its service around the world.

Piano Media offers a paywall service that multiple online publishers can sign up to, meaning that consumers only need to pay one subscription fee to access all the publishers’ sites.

After a successful launch in Slovakia, Piano Media expanded to Slovenia earlier this year with 9 publishers and 12 websites on board. In its native Slovakia, the service is proving popular with publishers. In February it was announced that 12 publishers and 50 websites were using its paywall. The current monthly price for access to all those sites is €3.90 ($5.11 USD). Early indications seem promising from Slovenia too, where the startup is claiming 37% more revenue per capita  than in Slovakia.

Piano Media CEO Tomáš Bella says that the new funds will be used to “Speed our expansion, recruit top talent, ramp up our marketing, broaden our sales channels and keep improving our software.”

Piano Media certainly offers an interesting alternative to traditional paywalls, which tend to be publisher-specific. ’Bundling’ multiple online publishers together into a common subscription was an idea Rupert Murdoch’s News International flirted with in the UK in 2010, but nothing came of it. The obvious problem is that users may not be keen to pay for access to sites they’re not interested in along with ones that they are. We’ll be watching closely to see whether consumers outside of Piano’s native part of the world take to the idea.