In melee combat, Barricade is slightly larger and more violent and savage, he has a flail thatís very deadly, but Jazz is faster and more agile, and heís probably more skilled in melee combat.
In firepower, weíve only seen Barricade use his gun once in DOTM, and that was when he killed a badly injured Que with one shot. But that was the same fun that was being used by Decepticon Protoforms which displayed rapid firepower, but it didnít seem to be that impressive. Jazz however, has displayed firepower that has burned a hole in Brawlís chest and staggered him, and it has ripped off tiny shards of Megatronís shoulder. Jazz probably has superior firepower, but I donít think itís fair to say that with confidence because weíve not seen Barricade get a proper chance to demonstrate his firepowerís capabilities.
This is close to going either way to be honest, Iíll say that Jazz would probably win the majority of times by an extremely slight advantage.