The Matsushita ECC83 (also known as a 12AX7) vacuum tube is highly regarded for its rich, warm, and detailed tonal characteristics, making it a favorite among audiophiles and musicians alike. NOS tubes fall within the Gm characteristic range of an average tube, as published in the RCA RECEIVING TUBE MANUAL, which states "Individual tubes, like any manufactured product, may have characteristics that range above or below the values given.
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