What up to all,
This is a dope website that has helped me out a fuck ton.
I stoked to be a member. Anyways....

Im a new owner of 505 and have a few questions:

Is there any way to apply any external effects to samples that are already in the 505 through the input and resample with those effects?

The 303 has a "remain" button which allows you to switch from one pad to another. For example, if three pads are playing and you want to change the levels while they are playing, you could press remain and pick witch one to modify. does the 505 have that option?

The 303 also has the option to reverse an unreverse at at the touch of a button. Can the 505?

hi
what mixer do you have?
i think that for adding fx from an external machine is not possible, except if you CD,MP3,PC,VINYLS etc>Mixer>SP505; if you try to do as you said i think this will cause a sort of feedback...

for the "remain"and "reverse" questions:
sp505 is more a studio machine than the 303. so it lack a little bit the "on the fly" feel the sp303 got. anyway, you can try the button "fx assign" to add fx to different pads (not the same as "remain" button, but...); you cannot reverse "live": you have to edit samples (try the "wave edit" button)...