The CM20T-BL two-way built-in loudspeaker can be used as a 16 ohms or 100 volt loudspeaker. In 16 ohms use, you can connect up to 4 loudspeakers in parallel on each channel of a standard 4 ohms amplifier. For 100 volt use, the CM20T-BL is equipped with a high-quality 20 watts 100 volt transformer w..