The new and improved JJ KT88 is the best-sounding current production KT88 according to a recent VTV listening session. They com-pared them all and the JJ was almost as good as the original MO Valve KT88. Very stable bias, handles high voltage well and sounds fabulous! Also works in most 6550 applications.The JJ KT88 has been with us for many years. It has become one of the modern benchmarks for which all new KT88s are judged. It provides very lively detailed performance with a velvet smooth midrange. The JJ KT88 has a great reliability record and comes in matched pairs or quads.