tube for my siverado

Discussion in 'Amps and Cabs [BG]' started by pedro24, Mar 6, 2002.

  1. pedro24


    Mar 5, 2002
    I look for a préamp tube for my silverdo ( i have a GT 12AX7 ) with more low-mid and less high and high-mid.
  2. Tubes do not work like that, they wont alter your EQ. In fact tubes in bass amps dont have nearly the same effect as in g****r amps. They may give you a softer, or harder sound, they may provide some breakup, or none at all. Sounds like you need an amp with more tonal control, maybe an Ampeg with the 9 band EQ, or a Trace with 12 band EQ.
  3. Preamp tubes do make a difference with SWR preamps.

    What's especially cool about SWR's is the ability to "overdrive" the preamp tube with a gain boost at the front end. Dial in the gain boost pedal just right with the preamp gain and overdrive the tube when you dig in. Don't worry about power amp distortion SWR's are designed to do this.

    Note in your Silverado Manual (quote):

    "NOTE: If you would like to overdrive the first TUBE stage, this can be accomplished by using an external preamp between your instrument and the Passive input. To obtain optimum sound when trying this, make sure the preamp clip LED is not activated. If this occurs, turn down your Gain control until the LED does not light. The first preamp tube stage is NOT monitored by the preamp clip circuit for this reason."

    I look for a preamp tube that overdrives easily and well, while maintaining a smooth, wide range when not overdriven.

    Finding the right balance and the right tube will really make the head "touch-sensitive" to clean (light attack), highlights of overdrive (normal attack), and more drive the more you dig in.

    Dig it.

    I've had good luck with the Sylvania long black plate JAN 5751. No noticeable loss of gain compared to the stock GT 12AX7A. Mellowed out the highs and smoothed out the bottom. Added a certain *sweetness.*

    You can find the NOS types on E-Bay for $10.

    Or you can go new 5751:

    Here are some tube reviews:

    I also like the Mesa 12AX7 preamp tubes.

    After experimenting with tubes in SWR head's for years, I finally found the tube I've been looking for.

    I can't tell you what it is. I bought a set of 4 matching 12AX7_A's from a Mesa Engineering employee in Petaluma. He bought a new Fender amp decades ago and immediately pulled the tubes out to test some Mesa tubes. This tubes were rediscovered when preparing a long distance move, still new, truly NOS, I bought the set.

    Dead quiet. Sweet tone. Wide Frequency Range. Overdrives just right.

    That was my journey to preamp tube heaven.

    Experiment. Test. Check 'em out.
    Who know's what you'll come across.

  4. pedro


    Apr 5, 2000
    Madison, WI.
    Who said you could use my name? Just kidding.
  5. Well, that certainly was a waste of time on my part.
  6. stevekim


    Feb 11, 2000
    los angeles, ca
    i've got good results from an n.o.s. rca long black plate 7025. the first thing i noticed was how quiet the amp became. the highs were also smoother and less harsh.