Complex sentence: Greenwald ended up with around 40 hours of iPhone recordings to work with at his home, where some snippets were played through a 4-track tape recorder or old pedals and some were looped or used as synthesizer patches.
Split into simpler sentences: Greenwald ended up with around 40 hours of iPhone recordings to work at his home. Some snippets were played through a 4-track tape recorder, others were old pedals and some were looped or used as synthesizer patches.