Any key differences in 5AR4 tubes in a PRRI?

Discussion in 'Glowing Bottle Tube Amp Forum' started by OzShadow, Nov 7, 2019 at 7:13 AM.

  1. OzShadow

    OzShadow Tele-Meister Silver Supporter

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    Any differences in tube brands for the 5AR4 used in a PRRI?

    The one that just came in my new one rattles noticeably. I’d rather just buy one than deal with warranty stuff.

    You can tap on the top and hear the tinkling metallic buzz. I checked each tube and the metal covers and this is the only one with issues. Removed you can clearly hear tiny resonant metallic sounds inside.
     
  2. Dacious

    Dacious Poster Extraordinaire

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    Ok so you should still try warranty. A GZ34 is a GZ34 is a GZ34. Old ones may last longer but any modern production version should survive years
     
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  3. uriah1

    uriah1 Telefied Ad Free Member

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    Actually Sovtek rectifiers are not bad for new stuff.
     
  4. RottenTheCat

    RottenTheCat Tele-Holic

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    5ar gz34 5u4 (in old pr) dont even break a swear in that amp
     
  5. Axis29

    Axis29 Poster Extraordinaire Ad Free Member

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    Only rectifier I've had go bad was a Ruby. It was a 5ar4, in my Twin, and it happened at a gig.

    I've had JJ's, GT's and a number of vintage ones. That Ruby was the only one in 35+ years of playing.
     
  6. Wally

    Wally Telefied Ad Free Member

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    Axis29, now the question is....what manufacturer built that Ruby labeled tube, right? It could have been a JJ, a Russian, or a Chinese tube.
     
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  7. OzShadow

    OzShadow Tele-Meister Silver Supporter

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    It functions fine, you can just hear it. Not through the amp that I can tell, just the resonating. I thought it was baffle buzz but could not stop it touching the baffle. It wasn't until I rapped my knuckles on the top that I heard the metallic buzzing sound almost like a mini spring reverb.
     
    Last edited: Nov 7, 2019 at 10:11 AM
  8. slider313

    slider313 Tele-Afflicted Silver Supporter

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    I'll second the SovTek 5AR4. It's a well built tube, virtually noise free and cost effective. FYI, most of the Ruby labeled 5AR4's I've seen are Chinese.
     
  9. Wally

    Wally Telefied Ad Free Member

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    I have measured some Russian GZ34 tubes that did not produce the voltage that should be produced. They dropped more than a GZ34/5AR4 should. Perhaps this is with some older Russian tubes, and they have changed the specs???.
     
  10. schmee

    schmee Poster Extraordinaire

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    I have had two import failures in brand new GZ34's. One Sovtek, One Ruby. "Flash zzzt" comes to mind. I try to avoid them. Not sure what the answer in new tubes is though. I have been using 5V4 old stock if I have to in lieu of risking another one of those. Fortunately I have old Mullard GZ34's for my main amps. They seem to last forever.
    Dont TAD and JJ make their own tubes? or their own designs anyway...?
    The Mullard reissue looks like it's their own design. I've had great luck with their 12AX7's. If I need one that's what I will try. The base may be an issue for amps with tube retainers though?
    [​IMG]
     
    Last edited: Nov 7, 2019 at 1:18 PM
  11. slider313

    slider313 Tele-Afflicted Silver Supporter

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    The recent SovTek GZ34's that I've tested have measured to spec. I have seen a few of their 5Y3's measure much higher than spec.
     
    Last edited: Nov 7, 2019 at 2:57 PM
  12. scelestus

    scelestus Tele-Meister

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    By higher do you mean durability or voltage?
     
  13. DavidP

    DavidP Friend of Leo's

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    You may want to consider a Weber Copper Cap WZ34 (https://www.tedweber.com/wz34) which is a drop-in 5AR4/GZ34 replacement, and runs the PT cooler as a 'rectifier with benefits'. Some folks like them (like me!) others don't. I've been running mine for over 10 yrs now w/o any issues. You would need to change the 'bear-claw' tube retainer to a spring type in a Princeton ads these have some heft to them.
    Also good to have as a low-cost backup in case your tube rectifier goes south at a critical time!
     
  14. Wally

    Wally Telefied Ad Free Member

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    JJ is a manufacturer. TAD is a German based rebrander....like Ruby or GT.
     
  15. schmee

    schmee Poster Extraordinaire

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    Thanks, That's interesting, I wonder who makes them for TAD? Some of their literature regarding the RCA type and GE types makes it sound like they are specific designs for them. "Octal power tube (Max Plate Watts = 30W) TAD 6L6GC-STR RCA-Style black-plate. TAD has the remakes of the all time favorite 6L6 classics by RCA and GE. The TAD 6L6GC-STR ..."
     
  16. slider313

    slider313 Tele-Afflicted Silver Supporter

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    They put out higher voltages than an original USA made 5Y3 would. Closer to a 5V4.
     
  17. zombiwoof

    zombiwoof Tele-Afflicted

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    I think TAD tubes are mostly Shuguang production. Shuguang does proprietary designs for TAD and other tube companies along with their regular production.
    Al
     
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  18. Dacious

    Dacious Poster Extraordinaire

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    I had an old Hammond 5Y3 in a Champ that did that. A ring on A notes. It's ba loose element.
     
  19. Dacious

    Dacious Poster Extraordinaire

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    Half the tubes you buy like Tungsols, Mullards, Marshall branded tubes are Shuguangs. The ones I bought direct are identical brown base tubes to the Marshall branded ones in it.

    I buy matched Shuguang EL34s and 6V6s direct from them on eBay. When I accidentally swapped the V1 tube with V3 in the Mini Jube which uses a cathode follower FX loop drive/recovery, it stopped working after 20 minutes. V

    is a Sov 12AX7WB, V3 is one of the metal-E mica bracket Shuguangs, both with Marshall branding. They work well in Mesa cathode follower stages too. You wouldn't nuse them in a Fender, but in a non-vintage V2-V3 stage they work very well.Swapping them back returned it to normal function.

    So far, never had a bad set buying direct. And even with postage, cheapish. The newer 6V6s have bigger plates like JJs.

    One of the local amp gurus here tried to destruction test them in a amp with 450vdc on the plates and they biased up easily were still working hours later. Tested later on they were within spec. He reckoned they output a bit more volume than the JJs.

    The new production stuff seems rugged as all get out.
     
  20. DavidP

    DavidP Friend of Leo's

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    Hey Dacious, got a link for the 'eBay Direct' source. How good is the matching??
    Cheers, DF.
     
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