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

Upscale is selling tubes again but with some limitations. I would not say you are buying spare tubes but I think tube rolling would be acceptable reason (better would be your tube failed). Probably only able to order 4 tubes every 180 days per his email. Oh. The tube tester is back online..

All Kevin's showing for sale are the four Russian new production brands which are pretty much the same tube with different labels and boxes. For NOS 5AR4's that work and may outlast you call Andy at Vintage Tube Services.  Don't waste your effort with e-mail.  The Matsushita 5AR4 which was made in a plant built and tooled with Mullard are very good tubes for under $100.  He also has couple of American made ones that are similar priced from Sylvania and GE.  If you just need one really good tube that will be the standard for comparison just buy a Mullard from him and be done. They have climbed to around $200 in the last couple of years.  Buying 5AR4's on Ebay is a serious crap shoot.

Stick to the American, British and Japanese made back in the days of yore! Current production Czech, Russian and Chinese may have reliability/longevity problems. No need to "tube roll" for the 5AR4/GZ34. The music signal does not pass through the rectifier tube. 

@russ69 oops, I forgot about the whole tube hoarding thing. And I wasn’t even thinking about it along those lines; ever since I bought that pre I’ve been considering tube upgrades and a spare rectifier in case the stock one takes a crap, so I wouldn’t be down, but I see what you mean.

@jackd okay, thank you for that, and I will consider Andy.

@jasonbourne52 I am confused on that; I understand that the rectifier tube is not in the signal path, but then I have read people talking how a different rectifier tube improved their unit’s sonic performance. As an example, I think I remember a blurb from Uncle Kevin talking about a rectifier tube upgrade for that tubed Prima Luna CD player he sells on his site. As I said, I am confused on that subject.