All our preamp tubes are stringently tested for noise and microphonics using Amplitrex testers driving an external amp. There is no extra charge for low noise and microphonics testing like with other tube vendors. Additionally the tubes undergo a battery of tests for basic performance characteristics and faults such as: Emissions, Transconductance, H-K and Grid leakage, etc... If a tube does not pass our strict performance criteria it's tossed or sent back to JJ Electronic for evaluation.
The Gold Pin JJ 12AY7 / 6072 is based on the same construction as the original JJ 12AY7. The internal components go through additional selection and processing during assembly. After working with the Gold Pin tubes for several years we can confirm they do test more consistently and sound noticeably different than the non-Gold Pin tubes.
The 12AY7 / 6072 is about 60% lower in gain than a traditional 12AX7. We recommend these in input stages where players are looking for more headroom and a cleaner overall amp. We also use them in specific stages of higher gain amps to tame and even out overdrive channels that go beyond the gain/distortion requirements of the player.
Keep in mind reducing gain generally has the effect of decreasing high end response. If that's not desired checkout the Gold Pin 12AY7 variant as it retains more bandwidth than the original non-gold pin tube.
