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svp-pro tube replacement?

Discussion in 'Amps and Cabs [BG]' started by allan grossman, Apr 16, 2002.


  1. Hey, all -

    I just got a new (to me) svp-pro today and decided to replace the tubes before I hung it in my rack. When I opened the preamp up I found five 12ax7 tubes instead of four 12ax7 and one 12au7.

    I have the proper tubes but have no idea which socket gets the odd tube. I saw something on tbl that said it went like this -

    12ax7 - 12ax7 - 12ax7 - 12au7 - 12ax7

    Does anyone know for sure?

    thanks -

    allan
     
  2. [Ed McMahon Voice]

    You are CORRECT sir

    [\Ed McMahon Voice]

    That's how it is in mine, If you're looking at the top of it from the front of it.

    BTW, what tubes / where from?
     
  3. tufnuts said...

    [Ed McMahon Voice]

    You are CORRECT sir

    [\Ed McMahon Voice]

    That's how it is in mine, If you're looking at the top of it from the front of it.

    BTW, what tubes / where from?


    Thanks a bunch, tufnuts :)

    I got electro-harmonix tubes - they come pretty highly recommended for the price. We'll see how they work.

    Thanks again -

    allan
     
  4. ZuluFunk

    ZuluFunk

    Apr 14, 2001
    Pennsylvania
    Why would you change tubes?

    Just curious.
     
  5. ZuluFunk asked...

    Why would you change tubes?

    Just curious.


    When the seller shipped the preamp he told me he had some extra tubes for it - which led me to believe at least some tubes had been replaced at least once. Since I have no idea what had been replaced I ordered a matched set of replacement tubes and figured I'd retube the amp before I racked it - that way you can be reasonably certain the thing will last at least a couple of years.

    Turns out it was a good thing I did - one of the tubes in the amp was wrong and I got that fixed before I put the preamp in the rack :D

    Also, preamp tube quality varies pretty widely - you can alter the tone of a preamp by switching tubes, so I got a set of pretty good tubes to use as a reference point - if I want a different tone I can swap them out. Replacing all the tubes in an SVP-PRO only cost me about $60 including shipping. I figure it was cheap insurance.

    I've seen NOS 12ax7 tubes go for as much as $300 - I guess if you want the tone you can get it - as long as you're willing to pay the price ;)