5V4GA rect tube for 6V6 plexi

[pjd3]

Hello,
I was curious to know anyone's experience with using a 5V4GA rectifier tube in 6V6GC plexi circuit, that had called out a GZ34. I ordered one from KCA after hearing from a few sources, respected tube amp guys, that it should be fine being that the power tubes are 6V6GC that wont be pushed terribly hard. It was shoot from the hip order from KCA after I got put off by a lot of complaints about current production reliability vs NOS. So, I sprung for a $36.00 5V4GA.
Many had commented that there would just be a small loss in B+ (5-10 volts or so) and there could be be a bit more sag but, only if you were pushing the amp - which I don't intend to do.

My ruminating fear however had to do with the first filter cap value. There were a few differing opinions. Someone had mentioned that a 5V4 data sheet had claimed 10uF as the called out first filter cap but then others said that the "5V4G" data sheets called out 60uF as a maximum value - the 10uF merely being a "typical" value and not a maximum.
So, at the end of the day I was felling better that for what I have in my power section, this rectifier tube would work. Mike had written that although the particular tube I ordered was not one of the "big three - RCA, Sylvania or Mullard I think it was" that the one I would receive is of a very high quality and robust tube.
So, I would certainly like to hear what you think about that. The worst that can happen is that I have a nice 5V4GA around and just need to get a GZ34!! - which aint the end of the world.
This amp is Sluckeys 6V6 plexi and its very very close to being finished. Then off the the amp tech for "bone-head inspection".
Thanks everyone,
PJD3

[pjd3]

It probably should have been mentioned that the 4 filter caps in this amp are all 32uF, those F & T double cap cans,

Thanks
PJD3

[10thTx]

Look at the tube data cheat sheet attached. Would you consider a 5U4GT instead of the 5V4GA?

With respect, 10thtx

[wpaulvogel]

The 5V4GA rectifier in a 6v6 plexi would be perfect. It will sag down similar to a GZ34 with big bottles. It’s also a 2amp heater like a GZ34 and indirectly heated cathode so it warms up slowly. It’s almost like a little GZ34. You don’t use the standby switch and the cap rating won’t matter.
A 5u4gb is 3amp draw directly heated cathode, not good.

[pjd3]

Thank you for the replies.
After getting paranoid about cap size I began looking at specs like HV current max's and started to feel a bit better about using it, and it did appear like many had used it in similar cases with no apparent problem, at least not during the time they've used one!
I"m going to put a couple of IN4007 diodes in the HV lines and go for it.

Thanks all,
Best,
PJD3

[sluckey]

Just use a GZ34. I've not had any problems in a 6V6 plexi. And I've not heard of any others having problems either.

[pjd3]

Hi Sluckey, I was never worried about having a GZ34. I was worried about in-rush or current draw with a 5v4gA but still ordered one because there are NOS versions very affordable and touted as very long term reliable. It was a decision I made a bit too quickly but, it's on its way and for a 6V6 with plate voltage that isn't through the roof, it sounds like the 5V4GA will work fine with the amp. Since this is my "Classic rock rock tone amp, I don't mind a little loss in plate voltage and the amp wont be pushed very hard. No one will allow me to do that!
I miss the 70's some times.

Thank you,
Phil PJD3