Review on SEVIZ Four Retro Bluetooth Speaker - 40W Stereo Sound, Bluetooth 5.0, 4 Hours Playback, Portable Speaker for Home, Outdoor & Travel, FM Radio, 10m Wireless Range, Wooden Speaker by Brittany Collins

for this money. The 40 watt and 20 watt models offer the best value for money. I recently bought 20 watt and 40 watt. Both can connect to Bluetooth Dual Audio, both speakers reproduce low, medium and high frequencies very well. ESPECIALLY AT THE CONCERT TOGETHER! 40 watts is significantly louder, as it should be. But the small 20 watts put away more bass. All I hear is super bass heavy EDM/Dubstep, none of the speakers had a problem filling up. Batteries, again "volume to max", definitely last 3 hours on each model! The 20 watt model has 2 drivers which appear to be larger than the 40 watt "4 drivers". I would say the 20 watt ones are about half a centimeter bigger and you can feel that! The processing quality* is perfect except for one small detail. The 20-watt volume knob shows that turning it counterclockwise increases it, but turning it clockwise does. 40 watt has solid positive keys!