straight pipe=LOUD and crackly
with resonator=loud no/or very few crackles
multiple resonators=much quieter and no crakles at all
I'm about to add a glasspack to mine to eliminate the crackles on it. If you do this though, make sure they put it in backwards. By doing this it won't change the tone or slow down the gasses. It will just reduc or eliminate the crackling and quiet it down a bit.