Ok so yesterday I used a freak back with .692 and luxe tip.
Using my phone decibel app. I was at 70-71dbs.
My friend has luxe and was same. Using same paint.
other friend had geo 3 with shaft 4 same paint. Don't know his bore. But his dbs was 70-71.
I went to my ul freak same insert same paint. UL tip. Got 75 dbs.
Accuracy was same.
I will also say I used a shaft 4 from an etha. Don't know the dbs. But the shot was definitely flatter and seems longer. But hard to say. This was on a different day.
Food for thought.