The DM series speakers deliver balanced, punchy bass sound and they can pump out extra power thanks to the new Class D amplifier and 4" woofer in each unit. Flick the switch to change from DJ mode to Production mode and the DSP settings will automatically create the best sound for each application. The DM-40 model comes in the updated design of the DECO convex diffusers which help deliver crystal-clear high frequencies in every direction. The woofer and tweeter are perfectly aligned. The grooves on the ducts reduce air friction so bass is tight and punchy, even if you position the speakers against a wall. The 4-inch woofer creates powerful sound without distorting.