Audio Research has been able to stand in the Hi-End audio industry for 50 years and continues to maintain a high degree of development vitality. It always adheres to the design goal of "High Definition" and uses "purely handmade mass products", so most of the manufacturing processes are the same. One level of handcrafting. In fact, needless to say, they also put special emphasis on the cleanliness of circuit welding during the production process. So they purchased expensive special fertilization agents specifically designed to clean residual impurities after welding. Almost every little thing has an impact on the sound, so they pay great attention to every production detail. Take the circuit board to the cleaning tank and directly use compressed spray to rinse the circuit board. Vacuum tubes have to work continuously for 48 hours, and the long-term tube burning is recorded in detail, and then paired according to the values. Over the years, Audio Research has launched nearly a hundred types of equipment. Due to different circuit designs, the applicable vacuum tube values are also slightly different. Audio Research records and saves all test data, and all qualified vacuum tubes are paired according to their values.