Recommendations please on a bias probe.,

Discussion in 'Amps and Cabs' started by davebc, Mar 3, 2015.

  1. davebc

    davebc Member

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    After all these many years there's no
    reason I shouldn't be doing this myself.

    Can you guys recommend a bias prob.
    6L6's are the priority right now,

    But I have amps running 5881's and
    34's as well.

    Thanks guys
     
  2. VJF

    VJF Member

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  3. Bluewail

    Bluewail Silver Supporting Member

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  4. Blue Strat

    Blue Strat Member

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    Compu Bias and Amp Head seem to be the most popular. I won a Bias Rite which has been ok, despite not super accurate readings, but there have been several reports of issues in more recent years.
     
  5. FourT6and2

    FourT6and2 Member

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    A good multi-meter is all one should need. And at least it can be used for other tasks compared to a "bias" meter that plugs into the tube sockets. But you need to learn how to use it properly—it's not difficult. Fluke makes high-quality meters that would most likely be more accurate than a tube-socket bias meter. But if you don't feel comfortable using test probes then a bias meter would be the way to go.
     
  6. bbaug14

    bbaug14 Supporting Member

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    This. You can also buy a tube insert that plugs into the tube socket and into the meter so you dont have to poke around in the amp. This only works if your amp doesn't have the 1 ohm resistors on the tube sockets.
     
  7. LPMojoGL

    LPMojoGL Music Room Superstar Supporting Member

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  8. Blue Strat

    Blue Strat Member

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    From another thread, the OP has been down this road and doesn't want to do it this way again.

    You're correct, but having to dig around inside an amp isn't for everyone.
     
  9. Trotter

    Trotter Supporting Member

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    The Compu Bias has the ability to match tubes

    My Bias Rite has worked well for a long time... no issues here
     
  10. TimD

    TimD Member

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    I've been using the Allesandro Bias meter for 12 or so years. Fantastic piece or gear and has saved me a ton of $$$.


    Sent from my iPhone using Tapatalk
     
  11. davebc

    davebc Member

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    Wow they all look really fantastic.

    I can't tell you how much I appreciate
    everyones input.
    This will be a huge help for me.
     
  12. RCCola

    RCCola (|@ / \ @ |.) Gold Supporting Member

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    I've had a Bias Rite for maybe 8 years. Still works. I wouldn't say it's high quality but it gets the job done.

    The plastic top plates that are above the pin holes tend to fall off, but they aren't necessary.

    Coincidentally, today, the plate that has the pin holes drilled into it detached from the base as I was removing a tube, but it snapped back on.

    Also, one of the posts on the the battery connector inside snapped off, but I get by by electrical taping the battery.

    What's that mean? Any device that lets you read current per tube will allow this, no?
     
  13. Trotter

    Trotter Supporting Member

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    It means in addition to the plate voltage and cathode current readings, it displays the calculated wattage for the tubes... I'm not aware of another bias tool that does this.

    http://www.compu-bias.com
     
  14. Monstercastle

    Monstercastle Supporting Member

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    I use my Fluke meter and a Weber probe.
     
  15. RCCola

    RCCola (|@ / \ @ |.) Gold Supporting Member

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    But, I assume the 'wattage' here is just using the cathode current and plate voltage. So, reading cathode current and plate voltage from any device is the same as CompuBias' wattage calculation.

    Correct me if I'm wrong, but a cathode current tool doesn't/can't measure screen current. Otherwise, it would display screen current instead of cathode current since plate current is what really should be used in calculating plate dissipation. The device needs to know the screen resistor value afik.
     

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