2. tech-talk
  3. 1279930694

Substitute 5V4G tube for 5AR4 tube

I have mostly PrimaLuna equipment, I.E. Prologue 3, 5, and 8
The diode tubes in the Prologue 3 and 8 are 5AR4 tubes (Chinese). I would like to know what sonic changes others may have found by substituting either 5V4G or 5Y3 in place of the 5AR4 diode tube. The 5V4G tubes I am considering are NOS RCA's. All signal tubes, 12AU7 and 12AX7 are Tungsram.
I have rotated RCA cleartops and BB's and still go back to the Tungsgram tubes, although I recently aquired some 12AU7 Slyvaina Gold Brand triple mica, extra rod, that I am experimenting with. I need more time to see which unit they may sound best in, but I did get as far as pluging them into the cd player and noticed right away a focused, stronger base.
128x128bradf
rodman99999
3,557 posts
 
While the 5V4 and 5AR4 can be interchanged in your circuit; you'll find the 5V4 less dynamic. A NOS Mullard(Blackburn Plant) 5AR4 will provide long life, dynamics, and a clean/smooth presentation(no sacrifices). ie: (http://cgi.ebay.com/MULLARD-GZ34-5AR4-CV1377-rectifier-tube-NOSNIB-/270598619300?cmd=ViewItem&pt=Vintage_Electronics_R2&hash=item3f00ef40a4) Many others on eBay as well.
bradf's avatar
bradf OP
288 posts
 
Rodman99999

Thank You for your advice. I will need four, 2 ea for the preamp and 2 each for the cd player.The tubes are somewhat spendy, but it seems the sonic upgrade in replacing the Chinese tubes should be a pretty good value. All the tubes I have replaced have made a significant difference, except for the RCA 12AU7 clear tops. They just didnt seem to make that much difference. They have since been replaced with some Tungsgram 12AU7's which I like alot.

Thnx again Mr Rodman99999
Brad
rodman99999
3,557 posts
 
One of the good things about the Mullards is their longevity. They will most likely be the last rectifiers you'll have to buy for your amps/pres(unless you keep them for the rest of your life). My experience has been that power supply mods make some of the best sonic improvements, and the better the rectifier: the faster, smoother and cleaner the overall presentation. Let us know how you like them. Happy listening and you're welcome.
gte357s
105 posts
 
Hi, I am resurrected this old thread because of similar reason - the 5ar4 is too expensive. Can u share your experience using 5v4g on the prologue 3? Is it worth the money or should I bite the bullet to buy the 5ar4?
bradf's avatar
bradf OP
288 posts
 
Replacing the PrimaLuna 5AR4 with is still on my list, although when it comes time to I think I will go for the Mullard GZ34. I recently purchased a Woo WA6-SE Headphone amp. Along with it I recieved a Soviet 5AR4 and a Sophia Princess Mesh Plate 274B rectifier tube.The Sophia Princess Mesh Plate 274B is a $160.00 upgrade which I think the cost of the tube is justified by the upgrade in performance. It just makes it a better sounding Amp.
Because of this I have drawn the conclusion that upgraded rectifier tubes are as worthy an upgraded as single tubes.
Hope this helps
More to discover