We've always been loud in the house while the babies sleep. We didn't want them to be light sleepers... especially since there are two of them!! They can pretty much sleep through anything now. We go to worship concerts or practices at the church and they fall right to sleep. It's amazing. Sometimes though, we need the sound apps or devices to help calm them down for nap/sleep time.
We live in a condo building, and where their room is located, you can hear people going in and out of their homes, and talking. So, we have a digital alarm clock that has built in sounds for their room. We turn it on at night time for them so they won't hear the kids playing outside, or whatever else might be going on. We have always used the rain / storm sound... it's Will & I's favorite.
We also use an app called "Sleep Pillow"... which they love as well! (It's free if you want to download it!)
The vacuum is always another option too. They have loved it since they were born, and still do.
Isn't it funny to think about things that we think we just couldn't live without?! How in the world did our parents get through the baby years without the cool gadgets we have now? : )
Do you use white noise, music, or a sound machine to help your baby sleep?