Note these db measurements are only valid as a comparison between the two guns with the understanding that a PC microphone isn't very accurate in its frequency response and other measurement problems such as nearby reflections exist. Nevertheless better than subjective listening with my ears.
Using Audacity on a laptop PC I shot pellets into the air so that pellet impact noise isn't measured. The noise floor is about 51 db so anything less than that should ignored. The Marauder is about 5 db louder than the R5M also the sound duration of the Marauder is longer too. They are both shooting JSB Kings, the Marauder at 850 fps and the R5M at 920 fps. The discharge noise of the R5M is really only a whoosh air. Unrecognizable as a projectile accelerator.
Sound is attenuated by air, more so with high frequencies than low frequencies. So what someone will hear will vary greatly depending on the distance from the source and doesn't follow the idealistic inverse square law.
I added some sound damping material to the shroud of the R5M as seen in the photos. I put one layer of foam against the shroud but not covering the vents. Then I added 2 turns of polyester felt. Since my early sound testing of the mod was flawed (I was measuring the pellet impact not the discharge noise) I don't have any before and after numbers. But subjectively it did make a noticeable difference.
I included some wav files what the shots sounded like.
Using Audacity on a laptop PC I shot pellets into the air so that pellet impact noise isn't measured. The noise floor is about 51 db so anything less than that should ignored. The Marauder is about 5 db louder than the R5M also the sound duration of the Marauder is longer too. They are both shooting JSB Kings, the Marauder at 850 fps and the R5M at 920 fps. The discharge noise of the R5M is really only a whoosh air. Unrecognizable as a projectile accelerator.
Sound is attenuated by air, more so with high frequencies than low frequencies. So what someone will hear will vary greatly depending on the distance from the source and doesn't follow the idealistic inverse square law.
I added some sound damping material to the shroud of the R5M as seen in the photos. I put one layer of foam against the shroud but not covering the vents. Then I added 2 turns of polyester felt. Since my early sound testing of the mod was flawed (I was measuring the pellet impact not the discharge noise) I don't have any before and after numbers. But subjectively it did make a noticeable difference.
I included some wav files what the shots sounded like.

