Marantz Model M1 Going Past Stereo
Marantz's marketing department calls the Model M1 a 2.1-channel amplifier, and there's some clever thinking behind that as a diminutive device like this often ends up in a home that isn't amenable to large speakers. An obvious move is to add a subwoofer to a pair of compact standmounts when desiring low-frequency thrills in smaller spaces. Without offering room calibration, the app has some handy functions to help in this regard. There's a low-pass filter (for the sub) and a high-pass filter (for the speakers), plus a subwoofer level control quickly accessed from the 'Now Playing' screen, so it's easy to set your 2.1 house in order.
Some competing products allow you to expand from 2.1 to surround sound by connecting wireless speakers. That's not on the books with the Model M1, even though sister brand, Denon, offers compact 'Denon Home' speakers that would do the job nicely. The amp can also process Dolby Digital and Dolby Digital Plus, but this is for convenience's sake, Marantz says, so people don't need to switch their TV audio output to PCM...