Ampeg introduced its first line of solid-state amplifiers at the 1966 Summer NAMM show and they were officially launched in 1967, which was right around the time that Fender and other amplifier builders were also beginning to experiment with solid-state designs. Ampeg's first series of solid-state amps featured their patented combo/piggyback Portaflex design available in several different wattage and speaker configurations. These amps had traditional blue Ampeg covering with a silver/blue grille cloth, but the control panels on the head units were much different and solid-state badging was very prominent. According to Jess Oliver, the very first solid-state Ampegs were prone to overheating that often caused components to fail, however, Ampeg quickly fixed this problem and by mid-1967, their solid-state amps were more reliable. Ampeg's first solid-state amps also utilized an electroluminescent control panel that glowed blue when the amp was on. The first series of solid-state amps was produced through 1968. Some of the earliest solid-state models may have black covering.