When a Player's hero uses an attack which ignores the target's armor soak value will it ignore the innate soak value of the target creature,not his toughness but the number next to toughness,in parentheses ?

Yes, the number next to the creature's toughness in the rule books or the number in the middle on the right of the creature cards is the creature's soak value (which is added to toughness to calculate total damage reduction).

Action card results which allow the attacker to ignore soak mean that only the target's toughness is used for damage reduction. Action cards that do this are potential lifesavers for players!

So the soak value,the number in parentheses next to the toughness, is the creature's default ARMOR soak valueactions that ignore armor soak value will ignore this even if I as the GM haven't give the creature any special equipment,right ?

Yes. The number is parenthesis represents a "default" armor soak if you do not give the creature a specific armor. As such, abilities that ignore armor soak (or points of armor soak) will affect this value just like armor.

Thank you both !