Date code: 57 - 22. Please review the photos for more detail. The tubes were tested for.
They were burned-in on a THD audio amplifier. OK balanced test results for Gm.
1.3/1.2 and 1.1/1.0 (low side). For Gm, 1.0 is the suggested 60% reject value.
For reference we use a calibrated Triplett 3444A Tester. Our standard service is US Postal 1. The item "12AX7 CBS Audio Receiver Guitar Pre-amplifier Vacuum Tubes Tested Pair" is in sale since Saturday, April 17, 2021. This item is in the category "Consumer Electronics\Vintage Electronics\Vintage Audio & Video\Vintage Parts & Accessories\Vintage Tubes & Tube Sockets".The seller is "chukv" and is located in Westwood, Massachusetts. This item can be shipped worldwide.