Engineered with the user in mind, the new PRL series is equipped with new bi-polar power units in complementary configuration: new oversize toroidal independent transformers deliver a high flow of voltage to the output channels, offering great bass kick sound and dynamic power reserve to spare! The PRL amps are equipped also with Proel’s exclusive OSC™ (Output Sense Clipping) circuitry which controls the clipping threshold of the system and tracks the available headroom, thus avoiding the creation of square waves. The circuit controls in real time that the signal is always sinusoidal either when the input signal is too high or when the mains power varies to –25% of the nominal voltage value of 230V AC or 117V AC. The OSC™ circuit can be deactivated through a command placed at the back of the amplifier. Heat dissipation is an essential factor of any power amplifier: the PRL amps feature low-noise, variable speed, cooling fans. A series of aluminium extrusion heat exchangers built inside each PRL amp, maximise thermal transfer. The PRL series incorporates multiple protection: soft-start on/ off 3-sec. delay, delay inrush current, DC voltage, overload or short circuit, thermal. A built in 24dB/ oct Linkwitz-Riley crossover filter provides 5 selectable frequencies, from 80Hz to 160Hz. A specific 4-pin SPK4MP bridge output is now provided at the back of the amplifier.