The Yamaha PSR-E363 has 2.5 W amplifiers while the PSR-E463 has 6 W amplifiers. Therefore, the PSR-E463 can produce fuller and richer sounds.
When the keys are pressed, the Yamaha PSR-E363 gives off louder and harsher clicking sounds than PSR-E463. However, this should not affect recording as the clicking sounds will not be recorded.