Mystic Invader according to the limb sticker. Per your advice I removed & measured the string & cables. Cables matched the sticker info perfectly, but the string was slightly over an inch too short!. I untwisted the string to match specs (still plenty of twist in the string), and put things back together. Then I shot a dozen arrows before heading to work.

The vibration is largely gone, not completely, but it is now quite tolerable. Noise reduced a little, but is still unacceptable. The sound isn' t quite as harsh, and I' m now pretty sure it' s coming from the string/cables. I' m a bit puzzled, since catwhiskers are all I' ve ever needed for string silencing.

I' ll need to visit my local Hoyt dealer for cam modules, as the draw length is now clearly too long for me after lengthening the string. Certainly more than the 28" marked on the sticker. I suspect the modules are not the originals. The nomenclature on the cams says A2B & A2T, if that means anything to anyone out there.

Despite some obvious creeping due to the draw length, I still shot those dozen arrows quite well. I believe this will be a very forgiving bow, especially when I get it properly fitted & tuned. Doesn' t surprise me since I' ve done well with this type of bow (long length, 8.75" brace height, heavy mass weight, moderate cams) in the past.

But it' s those same qualities, along with heavy arrows, that I assumed would lead to a quiet shot.

Thanks for the reply, Arthur.