NOS Tube Placement

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by JackBurton, Oct 9, 2016.

  1. Timbre Wolf

    Timbre Wolf GoldMember Supporter Gold Supporting Member

    Messages:
    9,195
    Joined:
    Oct 14, 2005
    Location:
    Berkeley, CA
    I picked these particular tubes because, out of literally dozens of different tubes I tried in each position, these were the ones I liked the very best for my taste (incredible clarity, brighter tone and more open character, more dynamic (less compressed) response, somewhat rough/raw breakup.

    - Thom
     
    DakotaRed likes this.
  2. grunf

    grunf Member

    Messages:
    110
    Joined:
    Nov 13, 2017
    Location:
    Amsterdam
    @Alan Dunn have you ever tried one of these (Mullard made in Australia)...I can get a bunch for 20$ each but cannot find any info about them (found some background info but that's it)

    [​IMG]
     
  3. Alan Dunn

    Alan Dunn Member

    Messages:
    731
    Joined:
    Sep 15, 2016
    Location:
    Australia
    Yes. I have them in my Marantz 8b. They are possibly early 70's issues. Very reliable as well - I have at least 20,000 hours on a pair of them.

    They come from the Hendon factory in South Australia.

    However, there were also a lot of these tubes stamped as "made in Australia" which were actually made in the former Yugoslavia by EI that were shipped to Australia after production stopped in Australia around the mid 1970's. I'd still rate the EI tubes as better than any current production types.
     
    Last edited: Nov 11, 2019 at 1:14 PM
  4. HotBluePlates

    HotBluePlates Member

    Messages:
    6,348
    Joined:
    Mar 27, 2017
    You have to look at the stamp on the tube to find the factory code for place of origin. I bought ~20 EF86s not long ago, most in Philips Miniwatt boxes, and all from a gentleman in Australia.

    Their actual origin was a mix of Blackburn Mullard, Heerlen Amperex, Munich Siemens, and others. You can't know anything based on the label/box alone (@Timbre Wolf already told you this elsewhere).
     
    Alan Dunn likes this.
  5. grunf

    grunf Member

    Messages:
    110
    Joined:
    Nov 13, 2017
    Location:
    Amsterdam
    so it is a mixed batch I've got five Mullards which are marked with kb/da code,
    other ones are Philips Miniwatt and one is Radiotrone.still need to go through all the codes. Will take some pictures during daylight.
     
  6. Timbre Wolf

    Timbre Wolf GoldMember Supporter Gold Supporting Member

    Messages:
    9,195
    Joined:
    Oct 14, 2005
    Location:
    Berkeley, CA
    What you're really looking for are the two lines of codes either on the lower sides of the glass envelope, or on the glass base, between the pins. Take a look at this site to get a better idea: http://www.tube-classics.de/TC/Tubes/Valvo/Phlipscode.htm

    For Philips tubes made in Australia, you might see the second line beginning with a "C". But these may not be Philips tubes - they might be Ei, from Yugoslavia, or BEL from India (looks like Philips style). Or, if you get lucky, they may be some of the following:
    B = Mullard - Blackburn, Great Britain
    ⊿ = Philips/Miniwatt/Amperex - Heerlen, Netherlands
    D = Valvo - Hamburg W. Germany

    Don't pay too much attention to the painted logos you mentioned above, as they do not confirm the origin. In fact, "Miniwatt" has been legitimately painted on valves from over a dozen different factories - so it really tells you nothing.
     
  7. friend33

    friend33 Silver Supporting Member

    Messages:
    3,590
    Joined:
    Oct 30, 2007
    Location:
    Colorado
    Magic Amps Crossroads - just installed all Mullards:

    V1 - ‘58 long plate f91
    V2 - ‘60 i61 type, Heath label
    V3 - ‘62 i61 type, Knight label

    V4/5 - ‘65 kM1 types, 45-slant-O getters

    V6 - ‘60 EZ81 D-getter Shield logo

    Sounds fantastic! :cool:

    On the American side of the pond, I’ve got a nice array in my At Mars Specialist. I’ll check out what I ended up with in there and post it tomorrow.
     
    Timbre Wolf likes this.
  8. grunf

    grunf Member

    Messages:
    110
    Joined:
    Nov 13, 2017
    Location:
    Amsterdam
    @Timbre Wolf thanks for explaining, I'll need to look at those once back home, I only have one picture on my phone I took yesterday showing C1A (quite blurry, so not sure if A is A or some other symbol, but looks like an A). So, C makes sense, not sure about 1A part.
     
  9. friend33

    friend33 Silver Supporting Member

    Messages:
    3,590
    Joined:
    Oct 30, 2007
    Location:
    Colorado
    So, for the At Mars Specialist (converted Filmosound), I’m currently running:

    V1 - RCA blackplate 5963 (12au7 type)
    V2 - JAN GE JG 12ay7

    Power - Pair of RCA blackplate greyglass 6v6’s

    Rectifier - GE 6087 (5y3 WGBT - indirectly heated/slow warmup)

    Sounds fantastic! :cool:

    The Specialist can take any 12a_7/5751 types in either preamp slot (came with old glass Sylvania at/ax in v1/v2). With the stock configuration it starts breaking up shortly after 3 on the volume knob. With the way I’ve got it set up, break up is more somewhere just after 6.
    I also liked it running with a pair of ay’s.

    I’ve got some different a ua/ay tubes, haven’t gotten around to switching all of those out for nuances.

    Yet...;)
     
  10. grunf

    grunf Member

    Messages:
    110
    Joined:
    Nov 13, 2017
    Location:
    Amsterdam
    Ok, so, I think I have four Blackburn Mullards (see pictures below). C1A code of the Miniwatts is actually 16 C8A, so, that is Australian made I think? Couldn't find any code on (super) Radiotron
    There is also 16 C01 or similar code. Two are few Ecc83 Philips ones marked with code, which I am no surprised about, there should be bunch of them here in The Netherlands...I am wondering who would bring Australian tubes all the way to The Netherlands..and why :) In any case, I think I got a nice batch for about 17$ each (got discount for buying all of them)


    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]
     
  11. grunf

    grunf Member

    Messages:
    110
    Joined:
    Nov 13, 2017
    Location:
    Amsterdam
    Found this on other forum:
    "I have some old Australian-sourced Miniwatt ECC83 that were made in the Yugoslavian Ei factory. The ones I have appear to be real 50s vintage, but there are a lot of copies about, also made by Ei but much later, with all sorts of names on them (I have a couple marked "Siemens", and some more marked "Mazda"). The Ei factory Philips code is a circle, broken at the bottom, with a blob in the centre, and the codes are a character shorter than usual. I have been told that a lot of Philips group valves supplied to Australia in the 50s were made by Ei."
    so, I guess 16 C01 is one made by EI Niš.

    https://www.head-fi.org/threads/little-dot-tube-amps-vacuum-tube-rolling-guide.563884/page-160
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice