Brake engagement completely silent...

 

Yes.

Is it so loud that it startles your neighbors enough to say "what was that?!"

 

It's not loud enough to bother my neighbour, but certainly audible when standing in the driveway.

If yours is completely silent then it might be of a special design.

 

Well mine doesn't make any sound at all and I'm quite sure that it's not a "special design"... I just went out to the car and tried releasing the EPB then engaging the EPB. Not a sound. No clicks, thumps, clunks, or any mechanical sound at all. If I would hear a loud action I'd take it into the dealer.

 

Well, that's how loud the OP's car is, which you called "normal."

What a bizarre statement. You think I got some sort of special secret prototype that's different from everyone else?! LOL!

 

Is there any chance that whether the electronic parking brake makes any sounds depends on whether the car is being parked on a level surface or on an incline?

 

My driveway is on an incline and testing it today, I found no sound at all while setting the brake and disengaging it with the dash switch.

 

I engaged mine tonight with audio off. I heard a very faint sound which was barely audible.

 

Same here. No sound at all...nothing.

 

It's not a click thump or clunk. There's no vibration. It's a motorized sound. A whirr or an electronic buzz. If you park in a garage it's pronounced as the sound will reflect off the wall. If you're at the supermarket in the parking lot with people and cars, and you're inside the car, you won't really notice it. The brake engages the moment the car is in park (assuming you have it in auto-engage mode) so you'd have to have the door open before putting it in park (to have a decent chance at hearing it)

Same noise made by all current:

Corolla
Camry
Avalon
Rav4
Highlander

and more I'm not aware of.

Other makes have a similar sound too.

Ford
Honda
Hyundai etc

Wouldn't be surprised if they all use a similar/same supplier/part.

 

What did you decide to do? Did you have your local dealer look at (and listen to) it?

 

UPDATE: So I have been playing around with this the past few days and can say I am no longer concerned. If I sit in my garage with the windows rolled down and either manually or shifting in/out of park, to engage or disengage the PB, you can still hear it but it’s not as loud at all, when compared to parking on my slightly inclined driveway.
In the garage I can still here the motor noise as it engages, which I would fully expect, but it certainly isn’t silent as others have mentioned on here and I do think it may be related to being on a level surface or not.
I will be sure to mention this to the dealer next time I am there.
Thanks for all the input!!