Pros:  improved depth, blacker background, crisper highs, more refined overall sound, small, flexible voltage/amperage/wattage (works with most DC wall wart type sources), great set of adaptors, inexpensive Cons: improvements are small (can’t rule out placebo effect), effect will depend on system quality (more noticeable with better headphone), will be more cost-effective improvements for many, attracts ridicule like... Continue Reading →