5AR4 rectifier tube question

     Keep in mind: there's a plethora of variables, between that 5AR4/GZ34 and what you ultimately perceive (media/components/room/ears/brain/perspectives).

                  OH, and: NEVER accept info, from a bogus* Intelligence Operative! 

                           *What they offer will typically be in character 

                                  Happy experimenting and listening!

I've tried a variety of 5AR4/GZ34 rectifiers, from a metal base, a fat base, to a JJ new production and a few in-between these extremes.

Audible sonic difference = zero. 

The fat base popped after a couple weeks of use.  Oh well.

I think there may be a case for differences in guitar amps but only from what I have read on those forums - their version of a tweak?

{I see that my metal base might be worth a few bucks on eBay these days..}

The first valve I changed on my SLP-05 was the rectifier. I started with stock tubes and finished with Blackburn. Day 1 and 2. I left the rest. They were matched very well.

Did it make a difference? I was going to sell the unit if I couldn’t contour the tone. It added greater detail in every region. I ordered a STR-1002-SUPER rectifier from STL. I also ordered their passive tube 15 band EQ with a STR-1001 for it. BOTH are "Super" rectifiers. I use a STR-1001 on a Decware ZP3, literally night and day.

Does it make a difference? This discussion reminds me of cables and fuses. There is the "show me", bunch and there is the "I tried it" bunch.. I’m in the latter. Everything matters, even driving home with the window down before a listening session.

@immatthewj 

Hi,

I have a Cary SLP 05 too and have used several different rectifiers after the stock Sovtek failed after three months and took both fuses with it.  

I rate the Sovtek as OK sounding and poor on reliability. 

I tried a Gold Lion and it was a mixed experience. Good dynamics but poor transparency and detail.  

For NOS I tried an off label Amperex and it had quite a bass punch but the treble was not refined.

Next was a Mullard f31 and it was excellent but not quite as good as the Mullard f32 which is cheaper and easier to find.  

The NOS Mullard f32 can be found on ebay under a variety of labels that Mullard made them for, e.g. Haltron, RCA and Westinghouse.  

There are a number of very knowledgable and trustworthy tube guys on ebay and they have served me well for NOS rectifiers and 6SN7 tubes for my Cary. 

The Mullard f32 sounds so much better in my system than any others.  Speed, dynamics, transparency and seperation, refinement, bass, midrage, treble, etc.  Reliability is by all accounts a last a life time purchase, mine has lasted 9 months and going strong. 

Mullard NOS GZ34 / 5AR4 f32 date code.   If you keep looking you should be able to find an unused version for -$150 or so.  

i still have quite a stash of nice old stock 5ar4/gz34 (uk holland japan) so if folks are desperate for a few of them i may be able to assist, just pm me... only in usa or canada please - i am not currently using gear that runs these...

i had accumulated quite a few these from the 90's and 00's when i was running my wavelength cardinal se amps (one in each mono block) so being the hoarder i am i stocked up way back then