2. amps-preamps
  3. 1323512295

fire spark in 5AR4 rectifier tube for PrimaLuna Pr

All of a sudden, I see fire spark in one of the 5AR4 tube in my PrimaLuna Prologue 3 preamp so I turn it off immediately. I tried it again, and the same thing happen. What is going on?

Does it mean my tube is bad that I need to replace it? Or there is something wrong with my preamp? I did some research, it seems people said it may be the capacitance is too high, but I didn't change anything, could it be something goes wrong in the unit that results in capacitance being too high? Did I already damage my unit?

Thanks.
gte357s

Showing 3 responses by gte357s

gte357s OP
281 posts
 
I tried switching the tubes, and the spark appears on one of the tube, so, it is in fact the tube has gone bad.

So, now, can I just replace one or do I need to replace both with a matching pair?
gte357s OP
281 posts
 
Yes, mullard blackburn tubes are too expensive. Any cheaper but good NOS alternatives? Also, if I don't want to spend too much, is it still worthwhile to get 1 Mullard Blackburn? Or better to get a match pair of new stock?
gte357s OP
281 posts
 
OMG, the 5AR4 must be extremely popular. They are so hard to find and so darn expensive. It seems I need to buy one JJ to replace it for now so I can start listening to music, it may take me a long time to score a pair of NOS.
More to discover