In the professional audio market for many years EX for its power amplifier made a large number of years of warranty adjustment, five-year warranty! Yes, EX promises that this is a 5-year warranty amplifier, which may be the longest warranty professional amplifier! To ask why so proud, because the designer in the design of it when they have decided to design them as "a stable and reliable, leather and durable, sound quality, balanced power amplifier." Five years warranty is so proud, proud of the amplifier, the quality of Jiaozuo. Worth your purchase and look!