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Reliable online source for matched valves / tubes

Discussion in 'audio' started by James, Aug 2, 2021.

  1. James

    James Lord of the Erg\o/s

    I'd like to refresh the valves on my newly acquired 20-year old preamplifier, which has a pair of 12AU7 and a quad of 12AX7. The current 'matched' pair of 12AU7s (Psvane with gold pins) are supposedly newish, but the 12AX7s seem to be original. One of the latter doesn't glow, but the in-built phono stage seems to work fine.

    Where can I easily and reliably get a new set of matched valves, and what can I expect to pay for something halfway decent. I think the preamplifier was originally equipped with JJ Electronic valves, so that is the baseline.

    Any advice from the valve/tube gurus would be much appreciated. I'm an absolute noob when it comes to thermionic devices.

    James
     
  2. slavedata

    slavedata pfm Member

  3. G T Audio

    G T Audio Trade: Manufacturer and Distributor

    Watford Valves...
     
    Andy1912 and simonpyeman like this.
  4. simonpyeman

    simonpyeman Active Member

    The pair matching from Watford Valves was spot on for my last order.
     
  5. DimitryZ

    DimitryZ pfm Member

    In the US/Canada it's TubeDepot and TheTubeStore.
     
  6. psd122

    psd122 pfm Member

    Another recommendation for Watford valves here.
     
  7. Tony L

    Tony L Administrator

    James is in NZ, so buying from the UK likely isn’t economically viable. Maybe Japan is a better bet. Don’t overlook eBay either, there are good sellers who sell tested paired valves, you can learn a lot from a seller’s feedback etc. For preamps I’d go NOS or tested strong every time. A decent pair of Mullards, RCAs, Sylvanias etc will last well over a decade of typical use, so why slum it?

    PS It is also well worth keeping an eye on local auctions, boot sales, swap-meets etc, I have done really well for valves/valve kit locally.
     
  8. James

    James Lord of the Erg\o/s

    Yeah, it sucks to be located in a remote corner of the globe. Google tells me the only regular stockist of valves in New Zealand is a guitar amp store. The trouble with NOS is it's hard to tell if they are really unused or just given a spit and polish, as I have no idea or equipment to test them. I'll check out some of the UK and US suppliers and see if shipping is economic. After all, six tiny valves can't weigh more than a kilogram, even with generous packaging, right?

    Thanks for all your suggestions so far. I'd be keen to know if there is an Australian retailer if anyone fellow Antipodean can point me to one.
     
  9. Tony L

    Tony L Administrator

    A lot of the better traders do post test results and their feedback will indicate end-user satisfaction.

    Do not fear used valves. It is only modern junk that fails in a year or two. I have a lot of ‘50s and ‘60s used valves that still work/test perfectly. As an example the late-50s TL12 Plus I bought from the local auction appeared to have its full original valve set installed. Sadly the GZ34 had taken a knock and gone to air, so was useless, but the EF86, ECC81 and two EL84s are all absolutely fine, even the power valves testing ‘strong’ on my tester. All appropriate ‘50s date codes. Same story with a old ‘50s Ferrograph mono reel to reel a neighbour gave me. Obviously high use as the paint was worn around the controls, some head wear etc, but the valves I was able to test (a Mullard ECC83 and EL84, again with appropriate ‘50s date codes) tested ‘strong’ and sound fine in my other kit.

    I’ve amassed quite a good stock of vintage valves now and the small signal valves (ECCxx/12Axx/EFxx types) tend to just keep on going. I really can’t see the point of compromising on fairly naff new-production valves when you’ll likely get a good decade or more out of far nicer vintage valves. Power valves are a different thing and I cringe at the price of Mullard EL34s, GEC KT66s etc. It is one reason I love the Leak stuff as ‘70s-80s Russian military EL84 equivalents are actually really good. My Verdier preamp, Leak Stereo 20, TL12 Plus and even my guitar amp are all stuffed with vintage small signal valves (Mullard everywhere aside from the latter which has some RCA and Sylvania for a more ‘Fender’ sound).
     
  10. James

    James Lord of the Erg\o/s

    I did not realise vintage valves last longer than contemporary 'reissues'. Is there an explanation why?
     
  11. Tony L

    Tony L Administrator

    I’ve no idea why, I guess just better production techniques and QC given it was mainstream technology at the time and a niche market now. A lot were produced for the military too, who obviously had pretty extreme reliability requirements.

    PS Any US valve marked JAN (joint army/navy) is obviously military spec. I suspect you should be able to find these easier than say vintage Mullards, Brimars, Telefunkens etc in your area.
     
    James likes this.
  12. davidsrsb

    davidsrsb pfm Member

    NZ will have been using CV spec valves in the old days, but I do wonder how many JAN spec valves might have escaped from Vietnam into SE Asia in the 60s
     
  13. earlofsodbury

    earlofsodbury Wastrel.

    Given the probability of overseas import, I'd add TAD / Tube Amp Doctor to the list for matched sets - they do a good job IME, including putting some hours on Premium Matched tubes before actual matching - worthwhile because values can sometimes drift markedly in individual valves after some hours use.

    Worth noting, too, that simply because a small-signal valve (esp. 9-pin) is not obviously glowing doesn't mean it's not working - sometimes construction or getter-flash obscures the filaments from view.
     
  14. eguth

    eguth pfm Member

    You are in N.Z. If you are considering importing from the U.S. I can recommend Eurotubes. I have bought JJs from them several times. They are excellent at importing and matching JJ valves. These can be dodgy: Eurotubes tests them, breaks them in, matches them and gives you good advice. I have found their prices reasonable- and for JJ valves I would not consider using anyone else- even the excellent Watford Valves here in England- who I have used. You can see I am a fan of JJs- but ONLY when purchased from Eurotubes in Oregon.

    I hope this helps.
     
    James likes this.
  15. James

    James Lord of the Erg\o/s

    Now I understand what JAN means! In what ways is mil-spec better or more desirable?
     
  16. Tony L

    Tony L Administrator

    I suspect in most cases it is nothing beyond maybe a more stringent quality control. There are some military variants that are compatible but designed for lower microphony, greater robustness, but I’d not actively seek them out. Just try to find some nice matched pairs (assuming that is how your amp uses them, remember each is a dual triode, so potentially a stereo valve) of 50s or 60s production from the top brands (Mullard, RCA, GE, Sylvania, Philips etc etc). Audioasylum has a wealth of tube-rolling suggestions so you may even find some tips for your specific amp.
     
    James likes this.
  17. slavedata

    slavedata pfm Member

    I had a very poor experience with JJ 7591As bought from Watford valves in my Fisher 500C. Watford gave me a full refund after questioning the bias settings of the amp. I think it was just a bad batch from JJ, I will never touch a JJ valve again and I now stick to Electro Harmonix 7591s. They may be oversized but they don't go over bright and run away.
     
    Si74 likes this.
  18. Sean K

    Sean K pfm Member

    I'll have a look in my box of tubes. I have some vintage mullard and GECs from a collection I rescued from an old chap in Sheffield who died; his family were chucking them in a skip, along with a couple of stereo 20s, a couple of 401s and a pair of the biggest tannoys I've ever seen. I had all the valves tested by a chap with an avo (in 2005, all carefully stored and unused since) and still have the data sheet he gave me with the figures.

    I can send them from Otipoti for you to try, and see if you like them.
     
  19. Sean K

    Sean K pfm Member

    Incidentally, I have what appear to be a 4 x NOS Mullard GZ 32s, mint and boxed, are they worth much?

    Edit: I've just had a look on Ebay, wow, ha ha! Something of a mark up on the 15 shillings price on the boxes.

    I might be posting in the classifieds shortly....
     
  20. Sean K

    Sean K pfm Member

    Update
    I appear to have a pair of Mullard ECC83s. They are apparently rated at:

    1) .72/ 85% & 69/ 82%.
    2) .7/90% & .6/ 84%.

    The printing on both looks mint to me
     

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