If all you want is a no-fuss audio monitor, the Bump and Baldwin both recommend VTech’s DM221 audio monitor, which consistently garners a lot of accolades. Using digital audio technology, the DM221 offers clear audio transmission and eliminates the crackle of analog models. A two-way intercom allows you to talk to your baby, while a five-level sound indicator can visually alert you to cries from the other room. The transmitter also features a soft night-light for your child. And don’t sleep on its compact size, which makes it perfect for travel.
Range: Range is the main drawback of an RF model, as audio monitors can roam farther out, and a Wi-Fi connection can theoretically be checked anywhere. We wanted an adequate range in a typical home—to be able to maintain a signal up or down a flight of stairs, across the house, and out on a patio or driveway, but we didn’t expect much beyond that. We zeroed in on monitors rated to about 700 feet of range1 or greater.
Notifications and alerts work by sending a message or email to your device when motion or sound has occurred. This feature is only found in the Wi-Fi monitors, and isn't the best feature for baby because it comes after the fact (sometimes up to 30 min or more after), it does not offer details of the type of sound or motion detected, and could get annoying with useless and excessive messages being sent. In the end, we prefer sound activation over notifications and feel that alerts and notifications aren't all that useful for keeping tabs on your baby.
Wireless encryption: This ensures that no one else can tap into your monitor’s “feed” and see what’s going on in your house. WiFi-enabled monitors are great for portability and range, but may be more susceptible to hacking. If you go this route, be sure to secure your home wireless network and keep the monitor’s firmware updated. Otherwise look for digital monitors with a 2.4 GHz FHSS wireless transmission.