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chu raki g w ma he th ased t pu nea with u and v e of ap logy [1 nvenie Four-w parent bulk media [10–33]. In the case of solid-state bulk media, due to high material dispersion, phase-matching can be obtained only if the pump beams have a finite crossing angle in the media. By using picosecond pump pulses, highly efficient high-energy noncollinear four-wave optical parametric amplification was achieved in a transparent bulk Kerr medium [10,11]. Tunable isolated 25 fs and 13 fs pulses were obtained by combining these sidebands into a single beam in a LiNbO3 crystal and KTaO3 at room temperature, respectively [19,23]. In the present paper, the cascaded FWM was studied theoreti-cally and experimentally in several transparent bulk media. We demonstrated that the center wavelength of the generated multi-color sidebands can be tuned by simply changing the nonlinear medium. Self-compressed multicolor femtosecond pulses with durations close to the transform-limited pulse width were ob-tained using cascaded FWM when one of the two input beams was negatively chirped and the other was positively chirped. A the