Daniel Fisher, Sweetwater’s synth savant, demonstrates some ideas for bringing external sounds into your synthesizer’s Audio In jack. In these examples he’s feeding the synths some background music from an MP3 player as well as an electric guitar (both dry and processed). Although Daniel is demonstrating on a Moog Sub 37 and a Korg Minilogue, there are many other synths with an Audio In jack including: the Moog Model D, Voyager XL, Sub Phatty, Mother-32, Minitaur, and all of Moog's modular synths, Korg's ARP Odyssey, Monologue, MS-20, and microKorg, Roland's SE-02, Novation's UltraNova, MiniNova, and Bass Station II, Arturia's MatrixBrute, MiniBrute, and MicroBrute, the Behringer Model D, the Access Virus synths, Casio’s XW-P1, as well as most of the Eurorack audio modules.
Moog Sub 37 Analog Synthesizer: https://www.sweetwater.com/store/detail/Sub37TE
Korg Minilogue Analog Synthesizer: https://www.sweetwater.com/store/detail/Minilogue
Pigtronix FAT Drive: https://www.sweetwater.com/store/detail/FatDrive
TC Electronic Flashback: https://www.sweetwater.com/store/detail/Flashback
Friedman Vintage T with Classic 90s: https://www.sweetwater.com/store/detail/VintT-MRTS90