I've also been complamented on my Pat's quietness.
But sinceI put the wisker biscuit on the sound has increased for the shooter. I hear a slap now that i thought was the STS until i shot a bare shaft and the slap went away.
I soaked the Biscuit in Armor All last night and drenched my fletchings today and now finally the noise level between bare shaft and fletched arrow is about the same.
I still think it was quiter with the Drop zone though.
I did remove one of my slight twang makers by dousing a non-pivoting bolt with thick string waxon my new Vital bow gear slider.
I slowly took it apart piece by pice until I found a bolt with course threads that had too much slack in it allowing it to buzz between the nut & bolt.

I guess the next move is listening to the bow while someone else shoots it.

I'll say this, it is way quieter than my neighbors recurve- but still not as quiet as it could be= silentj/k.

BTW one of my bosses brought his old bow out to work for me to evaluate. Old bear looking wood riser job. After seeing itI will no longer be so anal about my rigs if that bow used to harvest deer. OMG I can't believe how far we have come! ~ 30% letoff, no wall- pull until you reach your DL, 900" long, both cams rubbing the limbs- whow was it a sight.
I bet it had more than a slight twang!