We present the design of a novel single-cycle infrared source tunable from 2 to 10 μm. We simulate the optical parametric amplification (OPA) in BBO and the difference frequency generation (DFG) in AGS based on coupled second-order three-wave nonlinear propagation equations. We combine this with the unidirectional pulse propagation equation, which models the generation of the initial supercontinuum seed in sapphire and the final self-compression in YAG, ZnS, and GaAs, respectively. The obtained results indicate that single-cycle pulses can be produced in a tunable range of 2 to 10 μm.