heeeelp please audio reserch 5SE - resistor blew up

Its not the big 27kOhm that blew. It’s the 1k grid resistor to the 6550 pass element. OP sent a pic to me.

"New old stock" 6550. Members with no tube testers at home are at a HUGE disadvantage. Yes! Test before install is always a good idea but OP may not have access to a tube guy. Using NOS tubes in regulators is one of the dumbest ideas I know.

I have a tube tester at home and source my NOS Tung Sol from probably the most reputable guy on planet with awesome test gear Andy at Vintage tube
... your results may vary

IF you can’t hear the difference a NOS Tung Sol make in the power supply of a REF5se you need to upgrade your system, your hearing or both
stop by Seattle and we can swap in 4 nice NOS or the factory tube see how ya do......

enjoy the music.....

I also trust Andy to test NOS regulators and rectifiers. Using Tung Sol in two Audio Note components. T-S recommended by the designer.