Hey gents, I've been getting questions about using 12AX7s or 12AU7s in the Platinum. I highly recommend that you do not do this. These tubes do not fall within any operating region that the Platinum is designed to handle.
Please keep in mind that the LP expects to see 6922s or equivalents (meaning very close operating points). It isn't reasonable to expect that it can take an arbitrary tube type and make it work. While it is not visible to you, what the LP has to do to bring some of these tubes into operation is outside of its safe operating area. As long as you stick to properly operating 6922s it will remain well within its safe operating regime.
Near arbitrary tube rolling is what the Liquid Glass was designed to do.