Internet/networking companies reference your speed by kilobits or megabits or gigabits per second, instead of kilobytes or megabytes or gigabytes per second. There are 8 bits in a byte, therefore if you rate something in bits, it makes the amount seem like 8 times more to the untrained consumer.
500kbps is more like 62 KB/s. That's under ideal circumstances, without any bottlenecks on the other end, for wherever you are uploading to.
You know Tokyo Jihen is a supergroup, when you can't blame most of the members for wanting to pursue other projects.