Many over-ear / full-size headphones are easy to power and can reach satisfactory volume levels and excellent acoustic performance with tablets, smartphones or other portable players.
However, some high-end models require a headphone amp to reach their full sound quality potential. Just like some big speakers require more powerful amps to sound really great, the same applies to this category of headphone. Many high-end over ear headphones will benefit to some extent from a headphone amp.
Over-ear / full-size headphones may be open back, closed/sealed back, noise-cancelling or wireless designs.
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