chevydan04

So today I finally finished my project of replacing my timing belt as it was cracked in a ton of places. I replaced the idler tensioner and the #2 timing pulley. Also I resealed the upper and lower intake along with new orings for my fuel injectors.Got it started today and I have a loud knocking sound that increases with rpm of engine. I took a stethoscope accross both heads and noise did not increase with in valve area. Also did same along bottom end along oil pan. The only thing I can think of is my harmonic balancer is causing the sound, the two pieces have seperated. Does anyone have additional insight to this problem? How can I test my theory? No CEL light.