Probalyatok azt tízszer gyorsan mondani!
(That was probably very incorrect)
Not that much. :) You just misspellt "próbáljátok", and a prefix is needed for both of the verbs. Also, to make it more natural, I would use "ez" instead of "az", and I would add "egymás után" ("one after another").
"Próbáljátok meg ezt tízszer egymás után gyorsan kimondani."
Just wait for the actual Hungarian tongue twisters ;) :D Rap fast this line: "Fekete bikapata kopog a pepita patika köveken" (Black bull's hooves are knocking on the chequered floor tiles of the chemist's shop – okay, the scene is strange, too :D but it is a well known one.)
I cannot say it out loud right now 'cos it's 1053PM now :D But I recorded it, first slow, then faster. Here you are:
Sorry for the quality, it is taken with my Note Edge with others sleeping in the next room. :D