User manual YAMAHA BBT-110S

[. . . ] In order to get the most in performance and life out of this product, we recommend that you thoroughly read this Owner's Manual before using it. After reading the manual, please keep it in a safe place for future reference. [. . . ] Doing so may cause the device to fall or overturn, causing injury. * If the device is to be stacked , we recommend that the casters be removed from the amplifier/speaker to prevent overturning. Never use benzene, thinner or other volatile liquids for cleaning, as these chemicals may cause damage or discoloration to the finish. Always use a dry, soft cloth to wipe off dust and dirt. When choosing a power amplifier to use with your speakers, make sure that its power output matches the speakers' power capacity (refer to the Specifications below). Even if the amplifier's power output is lower than the speakers' power capacity, the speakers may be damaged when clipping of a high input signal occurs. Continuous high sound pressure level produced by electronic instruments. Popping noises caused by turning on equipment, or by connecting or disconnecting system-components while the amplifier is turned on. * Design and specifications may change without notice due to improvements. Check the specifications (power output/impedance) of the head amplifier/power amplifier you are going to connect to the speaker system and use it under the conditions that meet the requirements of the speaker system. [. . . ] Connecting three 4 speaker cabinets in a parallel configuration as shown below, results in a total impedance of about 1. Use the TWEETER LEVEL control knob on the unit's rear panel to adjust the output level of the tweeter. [. . . ]