The DX20 is a newer version of the DM20 mixer. The newer DX20 is metal and looks more PRO while the DM20 is plastic. The DX20's operation is almost identical to the DM20, but there are differences: in the DX20 there are no default stereo channels, but you can link adjacent channels so there is no problem. Digital input (SPDIF and USB) are the same. The analog GAIN knobs are back in the DX20 (the DM20 has only digital ones). The knobs themselves move a bit loosely, which can be a downside, for that we have quick access to all GAIN right from the desktop. On the plus side, it should be noted that the DX20's preamps have significantly less noise than the DM20's. Other new features of the DX20 include: input patching (in DM20, a physical input is permanently assigned to a channel on the mixer and cannot be changed); 6 DCA groups, 2 MUTE groups with physical buttons, 2 user layers freely configurable (inputs, outputs, DCA). More physical buttons on the desktop which speeds up the work (a little less clicking on the screen). MINUSES: a fan that starts 10 minutes after startup and runs all the time - normally it doesn't bother, but in a radio self-operator application it can be a problem; to connect with a tablet to the mixer you had to upload new firmware on the day. I was not able to connect over WiFi the mixer to the local network and control from the computer, only the DX20 as AP and the tablet over WiFi to the mixer. On the plus side, you don't need to use a special app - the mixer is operated through a browser. On the minus side, on the other hand, the color of the housing and especially the inscriptions (dB scale) at the potentiometers - they are much less visible than on the DM20 - this can be a big problem for the DX20, especially if we will be working in the dark or in the darkness