Would replacing the PSP's headphone jack improve the sound quality? Or would I have to a prosound-like mod to the PSP? The sound on the PSP-1000 is a tad scratchy and sharp. The iPod Touch's headphone jack sounds better then the PSP-1000's
Sound quality has almost nothing whatsoever to do with the headphone jack. The sound quality is dictated by the (gasp) audio chip, and speakers/phones.