Before a 909 power amplifier is completed and ready for delivery, it passes through a series of assembly stations in the Berlin factory. From the hand-assembled circuit boards, the soldering points of which are meticulously checked before installation, through the selected transformers to the computer-aided measuring station, around 100 hours of production time pass – this adds up to 7 days of test run with further intensive quality controls up to a detailed final hearing test under real conditions. This elaborate manufacturing process ensures that in the end the customer receives a product that is exceptional in every respect.