For his first few records, Prince used typical keyboard instruments of the late 1970s, including a Oberheim 4 Voice, a Moog Polymoog 203a, a Moog Minimoog, an Arp Pro Soloist, an Arp String Ensemble a Hohner Clavinet and a Fender Rhodes.
From Dirty Mind onward, Prince pared back his set up and focused on synthesizers and pianos. His primary synthesizers around this time were the Oberheim OB series (OB-X, OB-Xa, OB-SX, OB-8) and the Arp Omni-2. He also used acoustic pianos and the Yamaha CP-70 and 80.
Prince first used the Yamaha DX7 on Purple Rain, and he then switched almost exclusively to digital synthesizers on subsequent albums. On Parade he used a Fairlight CMI and, on Sign O The Times, an Ensoniq Mirage. For Lovesexy, Prince used a Roland D-50, an E-mu Emax and an Ensoniq ESQ-1. He also used a Hammond B3 organ on these albums.
Prince then used a series of "rompler" synthesizers - digital, sample based keyboards. This included a Korg M1 and Korg T3 around Diamonds and Pearls and a Roland JV-80 and Roland JD-800 from Lovesymbol to Rave Un2 The Joy Fantastic.
For Emancipation, Prince introduced the Clavia Nord Lead synthesizer, a "virtual analog" keyboard that emulated his older analog synthesizers. He also used his Oberheim OB-8 on Newpower Soul and Rave Un2 The Joy Fantastic.