I have an old DS411+II with 2x 8TB and 2x 12TB WD Reds. While they're not that loud, the entire setup made the cabinet underneath vibrate enough that it was a problem for me. Instead of hiding the NAS, I had success placing it on anti-vibration pads, similar to these, https://www.amazon.com/LBG-Products-Anti-Vibration-Conditioner-Compressors/dp/B07KFZ1G6W

Not sure how many cameras you have, and how much data is to be written, but there was a controversy a few years ago wrt. CMR vs SMR disk technology which you may look into if relevant, https://www.howtogeek.com/803276/cmr-vs.-smr-hard-drives-whats-the-difference/

Examples (scroll down to Specifications and click on the "+" sign to see what technology they use):

- https://www.westerndigital.com/products/internal-drives/wd-red-sata-hdd

- https://www.westerndigital.com/products/internal-drives/wd-red-pro-sata-hdd

- https://www.westerndigital.com/products/internal-drives/wd-red-plus-sata-3-5-hdd