5AR4 rectifier tube question


I am sort of shopping for one or more 5AR4s for a Cary SLP05 power supply because I’d like to have at least one spare and because I’d maybe like to roll two or three ad see if I can hear an improvement or vice versa. I make no claims of knowing much about the vacuum tube game; occasionally I get lucky & stumble on something that really works for me. As far as the 5AR4, I did a hit at Uncle Kevin’s site, and there were some that looked interesting (I am thinking of one in particular, it had a Japanese sounding name that started with a ’M’) but when I click on it, all I get is a picture of Uncle Kevin’s screaming face telling me "not to buy tubes" (later, when I finally took time to read, apparently his tube tester is down).

So I started doing hits on Ebay, and oh my gosh! I was inundated with choices and the variation in prices! Which do I stay away from and which should I be interested in? Would a 5AR4 from Bugera also be suitable for what I’d want to use it for? Could a rectifier tube provide a big sonic upgrade if I spent enough money on it? Can I make a sonic upgrade from what I believe (I haven’t opened up the power supply yet) is the stock EH 5AR4 without breaking the bank? I would be totally good with the $50.00 range and picking up 2 or 3 different ones to play with if those with experience thought I could improve the power supply in that range. If I had to I guess I could go more (the $100.00 range) but I probably wouldn’t be buying too many of them, and I was kind of HOPING not to go much over that.

Anyway, thanks in advance for the input; I always consider it part of my education.

immatthewj

@rodman99999 

the UK Bugle Boy arrived today.  I can not find any actual ETCHING in the glass, just what is printed on the glass.  It does state that it is a Bugle Boy "MADE IN GT. BRITAIN" and in very light, hard to read print, underneath the "5AR4-GZ34", it says "B5L2."   In the approximate middle of the glass, underneath the "Amperex" logo, is a "66" with a "14" underneath it. And there is a hole in the guide pin.

I am going to install it right now.

     The hole in the pin is a giveaway and with the code’s starting with a B: should be a Mullard from the Blackburn plant.

                How many teeth are there, in each side of the top mica?

Cary could have made a removable access panel for the tube in the side of that power supply.

But, @rodman99999   I should have read your reply more carefully before I took it apart again and then put it back together.  I seem to believe in measuring once & cutting twice.

However, if I counted correctly (& I did actually count twice) there appear to be ten total teeth in the top mica (so I am ASSUMING) that there are 5 per side).  The top mica is a shiny silver like color.  The bottom (mica?) is clear and has two semi circular notches in it.  As does the top shiny mica, 2 notches with the teeth in between.

Does ten sound right?  I was bitching about Cary not putting an access panel in it, but it's really not that hard to get down and remove the bottom, so I can easily look at it again.  I've got the rectifier tube warming up right now, but I haven't lit all the other tubes yet.

 

    Some have four, some seven, but: forget the notches.

                                Not important!

                               How's it sound?

    

     Here's something you may find interesting.

     There are some Mullards compared, for plate structure, etc and the last two both have the 5 tooth, top mica.

      Just a way to close in on the valve's year, but: not nearly as important as the condition, strength and sound.

https://www.google.com/search?q=identifying+mullard+5ar4%2Fgz34&oq=identifying+mullard+5ar4%2Fgz34&aqs=chrome..69i57j33i160.14529j1j15&sourceid=chrome&ie=UTF-8#kpvalbx=_5wJeYqXzL7CO9PwPpqq18AQ15