In .177, my Huntsman Regal (regulated) with a DonnyFL moderator (tanto, tatsu or Sumo) is not as quiet as a stock.177 Marauder. It is not just the sound of the air blast, but the mechanism on the Regal adds to the sound. A Daystate Red Wolf with moderator (.177) is very quiet. All that being said, I can shoot the Regal in my backyard. Good luck
a .22 is a bit louder in my opinion. When i bought my Regal Huntsman regulated in .177 from AOA it came with a Moderator provided by Daystate that had been epoxyed on. That moderator is not very good and with that installed I would not shoot in my backyard due to the noise. As mentioned, i replaced with and aftermarket moderator and that is much quieter. I have no idea if that same moderator is provided in thee latest version of Revere. I heard that you can call AOA (or perhaps your dealer) and request that the moderator NOT be glued on. I was able to remove it but the moderator and adaptor could not be separated and I had to buy another adaptor.Good luck!