Recommendations for quiet hfc
 

I am currently running FI CBE and FI HFC which have given me impressive gains and I've loved the aggressive rumbling noise.

However I work late hours and come and go at very early and very late times of day. I have also moved into a neighborhood where out of consideration for my neighbors I would like to replace my HFC with something quieter with absolutely no rasp if possible while maintaining the gains.

What are my options? Has anyone else wanted to make their exhaust sound 'quieter' during start-up and idle? What route did you go?

Thanks

Are you already running resonators, i.e., 18" resonators and resonated HFCs?