The only difference between these two are its size. HDD1630 has 6 GB of capacity while HDD6630 has 30 GB of capacity. Both these players have backlit touchpad and brand system SuperScroll for quicker navigation. Voice recorder and radio functions are present.
A single charge on HDD6330 provides up to 15 hours of non-stop playback while on HDD1630 provides upto 18 hours. These players will hit the market in October.