Sziget (Budapest) is Europe’s biggest multi-genre festival. Italy doesn’t have an equivalent single mega-festival, but it has a constellation of smaller ones in better settings.
Plan this trip →7 days, 500+ acts, 60,000 daily capacity, Obuda Island on the Danube. €300–400/7-day pass. International, massive, camping-focused.
For the same budget and time, you could do: Firenze Rocks (4 days, €200) + Lucca Summer (2 nights, €140) + Pistoia Blues (1 night, €50) = 7 days, 3 Tuscan cities, no camping, real beds, Italian food between shows. Or: Kappa FuturFestival (2 days) + Torino Jazz (3 days) in Turin.
Sziget: if you want the mega-festival experience, camping, meeting 100 nationalities. Italian festivals: if you want world-class acts in medieval/Renaissance settings with real food and hotels instead of tents.