6BQ5/EL84 and 7189

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by Keith Free, Sep 8, 2006.

  1. Keith Free

    Keith Free Member

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    It appears the 7189 tubes are a higher voltage--could i use these in my Dr Z Maz jr?
    also............
    Anyone have any reviews on the RCA EL84 Blackplates from 1950's?

    Thanks Keith
     
  2. slider313

    slider313 Silver Supporting Member

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    I believe they handle higher voltage and you can use them in place of el84/6bq5's. I think the 7189a's are the type you cannot use as a drop in replacement. I'm not quite sure if the "a"'s draw too much filiment current as opposed to the regular 7189. Maybe Old Tele Man can give us the specs and the reason they differ. OTM????
     
  3. Blue Strat

    Blue Strat Member

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    7189s and 7189As are both drop in replaceable for EL84s. The opposite is not true.

    Of course, this assumes that the tubes you have are OK and somewhat matched.
     
  4. AdmiralB

    AdmiralB Silver Supporting Member

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    My experience with later ('80s) Sylvania/Philips production is...they were all built to the 7189A spec, much as all Sylvania 6L6s by this time were spec-consistent with 7027A. As with 12AX7/7025, it was economically advantageous to build to the higher standard and run only one design.
     
  5. Bloozcat

    Bloozcat Member

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    The 7189(A) might be a good choice in an amp that runs higher plate voltages and eats EL84 tubes (AC30's anyone?).

    The Reflektor Russian Military 6P14P-EB (EV) 7189 (EL84M) is one of these really robust tubes that can take the high plate voltages. They're a little on the bright and edgy side and not as warm as many good NOS EL84's, but in the right application, they sound pretty good. They were selling for $10.00 a tube, so they were a great deal as well. I have a quad of them and I've used them in darker sounding amps. They seem to excell in this application. They need a couple of hours to "break-in" and mellow out before they sound their best.
     

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