7591

7591 is a numeric designation used in several classification schemes and may refer to different items depending on context. The term is most commonly associated with a vintage vacuum tube type used in audio equipment.

In vacuum tubes, the 7591 denotes a power output tube built for high-voltage circuits. It was produced by multiple manufacturers in the mid-20th century and used in radio receivers and audio amplifiers to provide power for output stages. The device is typically described as a beam power tube with a relatively robust envelope, capable of operating at higher plate voltages than small-signal tubes. In vintage gear, it is prized by technicians and enthusiasts for its sound characteristics and reliability; however, availability of new production has diminished, making refurbishments or sourcing used stock common.

Beyond vacuum tubes, 7591 appears as a generic model or part number in various product catalogs and inventories. Without context, the number does not convey a specific specification. Users should refer to accompanying documentation to determine its intended function.