Dieter Bohlen

In a user-uploaded photo, Dieter Bohlen is seen playing a Sequential Circuits Prophet-5 synthesizer. This suggests he may have used the Prophet-5 for bass and pad sounds in the song "You're My Heart, You're My Soul," similar to how others use VST versions of this synth for those elements.

In a user-uploaded photo, Dieter Bohlen is shown with the E-Mu Emulator II, identifiable as the prominent blue synthesizer at the bottom of his equipment rack.

It's the grey Roland synth at the top of the synth rack

In a user-uploaded photo, Dieter Bohlen is seen with the Sequential Circuits DrumTraks drum machine positioned behind him.

In a user-uploaded photo, Dieter Bohlen's FX rack appears to feature a Lexicon PCM-70 Reverb unit at the top.

In the right corner you could see Roland TR-808 drum machine. Dieter used it on such tracks as Modern Talking's "Stranded In The Middle of Nowhere" and "It's Christmas", and on C.C.Catch's "Tears".

In the bottom right corner you can see Dynacord Add-One.

In his book, Dieter Bohlen mentions owning two Prophet synthesizers. The Sequential Circuits Prophet VS is visible in the background of a user-uploaded photo, supporting this claim.

In a picture featured on Bremen Eins's article titled "7.2.1954: Geburtstag Dieter Bohlen," Dieter Bohlen can be seen using the Deltalab Effectron II ADM 1024.

In the video "Modern Talking - Geronimo's Cadillac (Peters Pop-Show 06.12.1986)" by ModernTalkingVEVO on YouTube, the Yamaha DX7 can be seen as a prop. The distinctive "BASS 1" sound from the DX7 is audible in Modern Talking's "Geronimo's Cadillac" and C.C. Catch's "Stop Dragging My Heart Around," along with other sounds from the DX7 featured in various songs produced by Dieter Bohlen.