I pretty much copied this setup, after buying a Fein.
I love my Fein! I am very happy with this set up. . I have to fiddle with it now and again to get the suction where I want it. I keep tweaking it and it is just getting better and better. I do not know why I didn't do this years ago. Other than the vacuum I probably have less than $8 in PVC but the Loc-line cost around $70. for the two machines I have. Not that much for one.
The loudest sound is the air sucking. It is louder than the noise of the saw and the vacuum. The Fein is a couple GB louder than a Festool and a couple hundred cheaper. I do not know how to make the air sound quieter. I think if you turn off your aids it will not bother you.
I also do not have the "trap" that Rolf added, but I may some day. This setup is simple and effective.
I use to have a box fan with a filter and used the saws blower. No comparison. I have not vacuumed my saws since I made this set up and I can go to bed at night and breath after time in the shop.