QA 1004 power amplifiers are built to work hard in the tough environment of pro audio. Service and maintenance is easy as the internal architecture is laid out for easy access by a qualified technician. The sonically superior output stage is composed of a generous abundance of output devices for greater electronic stability and sonic fidelity. QA series amplifiers are manufactured to a standard accepted as desirable practice for a concert standard power amplifier. Heavy gauge welded 16-gauge steel chassis with vibration proof fittings, and an emphasis on over-engineering, guarantees years of trouble-free service in the most demanding environments. Quest set about a design and layout for easy service, not easy manufacture. A minimum of disassembly is required for testing and maintenance meaning lower operating costs and longer amplifier life.