just got new tubes and...

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by john archer, Dec 10, 2005.


  1. john archer

    john archer Member

    Messages:
    203
    Joined:
    Nov 21, 2005
    Location:
    Lansdale, PA
    I just picked up 3 mullard 12ax7's for my marshall 1987x plexi ri. Can someone tell me which tube is considered v1? The 3 tubes tested out strong(nos). Is it true that v1 is the spot to put your best tube in?
     
  2. Reeek

    Reeek Member

    Messages:
    1,208
    Joined:
    Feb 1, 2005
    Location:
    Reno, NV
    For the most part, that's true for best effect from a good tube. Even though all three tubes are Mullards, you may want to try them in various sockets because one of those three Mullards may yield better tone to your ears than the other two in V1. Mullards are outstanding preamp tubes. Good luck.
    Having a schematic would be easit to find V1 of course. I can;t see why you couldn't get on the Marshall web page for reference.
     
  3. doctord02

    doctord02 Member

    Messages:
    1,066
    Joined:
    Mar 11, 2004
    Location:
    San Mateo, CA
    v1 on a Marshall 1987RI will be the tube farthest away from the power tubes; looking at the back of the amp, the v1 tube will be the first tube on the left side of the chassis... In other words:

    v1 - v2 - v3 - V4 - V5

    V4 and V5 will be the power tubes and v3 is the phase inverter.
     
  4. john archer

    john archer Member

    Messages:
    203
    Joined:
    Nov 21, 2005
    Location:
    Lansdale, PA
    Thank you much, I wasn't sure if it went left to right or vice-versa. I will just experiment with different combinations to find the best tone.
     
  5. VintageJon

    VintageJon Member

    Messages:
    155
    Joined:
    Nov 3, 2005
    Location:
    Austin TX
    In "Good Design Practice" the tube nearest the Input jack is the 1st preamp stage.

    -Jon
     
  6. daneswede1

    daneswede1 Member

    Messages:
    195
    Joined:
    Jun 21, 2005
    Although your Mullards tested fine they sometimes have a little problem with microphonics in the V1. If they do this to you dont flip. They are still good tunes and you can use them in the V2-V3 slots just fine. May want to look into a Brimars 12ax7 for the V1 if this happes . Good Luck.
     
  7. john archer

    john archer Member

    Messages:
    203
    Joined:
    Nov 21, 2005
    Location:
    Lansdale, PA
    Thanks...I have tried diiferent combinations and am happy with it now. I'll tell you though that the 1987x ri is a nice, very responsive amp, but the highs can be a bit piercing. I just got some mullard el34's for it. I am also going to get the new celestion heritage g12m 20 watters for my 4x12. I am going for that eric johnson violin lead thing. The sound ej gets on desert rose I think is just incredible, a bit more rounded than I currently have now. I think all said and done I will try strat-chandler tube driver-fulltone tte-marshall(bridged). I used to run a lexicon mpx-1 in the fx loop, but I found the tone to be muffled too much. Does anyone know if adding a tube reverb unit to the above would muddy it up too much? Is ej getting his echo just with an echo plex or is there some reverb added in there too? I think he now does most of his signal processing post mic, but I was thinking back in his a via musicom days.

    Thanks,

    John
     
  8. daneswede1

    daneswede1 Member

    Messages:
    195
    Joined:
    Jun 21, 2005
    Hey, Read your post. Eric JOhnson uses a 1968 59SLp 100 watt and a 1967 of the same . He also mainly uses tube driven pedals and fuzz to drive the amps bridging the channels. The reissue 87x 50 watt Marshall you have I have never heard. What year is it?. YOu mentioned it is a little to bright. Maybe have the bright cap cut out of it and youll like it better. My tech mentioned hes done that to a few older non master volume Marshalls and it warmed them right up! Not sure if yours would benefit from this. I do know your reissue is a PCB board though. I also have reissue Marshall. The Marshall 2203 JCM800. Not all the parts in the reissue JCM800 are like the originals. SOme of the parts are chinese. Sounds good though to me. Has Dagnall Transformers in it.
    ANyway AS far as your 87x you may want to try a Tonebone HOt British 12ax7 pedal out. Not as noisy as the old Chandler TUbe Drivers. I used to run the Chandlers back in the 80s. They are good racks/ pedals but somewhat noisy. ALso, If you have the money try looking at the Valvedriver by www.pedaldoctor.com. It will set you back $400 though. It is basically a revamped Chandler Tube Driver but with a better more quiet transformer and has a nice buoild to it. I mgonna try to post a pic of it hold on.......Did you buy the original Mullard EL34s? THose things would cost more the nthe head you own!!! Im not sure id be spending $800 dollars on original mullards to put in a reissue 50 watter?I like just regular C wing Svetlana EL34s in mine. Did you buy the reissue Mullard EL34s?
     
  9. john archer

    john archer Member

    Messages:
    203
    Joined:
    Nov 21, 2005
    Location:
    Lansdale, PA
    The mullards 12ax7's are branded united electron, rca, and motorola, but are mullard maufactured dated 1966, 1976, 1977, tested nos. The el34's are also mullard manufactured but made for slyvania dated 1969, 1972, are single halo getters(xf-2 date codes), and both tested nos. The tubes ran about 350.00. The bright cap is alrealdy out of the circuit. Someday, I think I will bite the bullet and get a '67-'69 marshall 100 watter. but for now I am trying to work with the ri. Thank you for your response though.

    John
     
  10. john archer

    john archer Member

    Messages:
    203
    Joined:
    Nov 21, 2005
    Location:
    Lansdale, PA
    oh...also the 50 watt ri is a 2002.
     

Share This Page