Mesa 12AX7's vs. SPAX7-A

[PinkFlydxx]

Mesa is calling the SPAX7-A a "premium" low microphonic preamp tube - at a $4.00/tube higher price than the standard 12AX7.

Is it really significantly better than a standard Mesa 12AX7 preamp tube, and is it suitable for all 7 preamp tubes or better in a few locations?

Thanks.

 

[MrMarkIII]

Mesa recommends it for V1. Sound-wise, only your ear can be the judge. It is tested for quietness and low microphonics, which doesn't necessarily mean better tone.