PSA for tube amp owners, yes this means you....

Discussion in 'Marshall Amps' started by Michael Inglis, Aug 18, 2019.

  1. Michael Inglis

    Michael Inglis Active Member

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    https://www.monoprice.com/product?p...ALFSR9nD-UuB0DUAuUZNqNSO2hWvdQDRoCmC0QAvD_BwE

    EDIT: The one on monoprice only kicks on at 112v but thats still workable, but anything lower than that wouldnt be very useful. Like the ones that kick on at around 105v (-12%). This is what it says about this one...

    Additional Information:
    • Voltage Regulation: +10%/-12%
    • Input voltages over 128V are reduced by 9.6%
    • Input voltages between 103 and 112V are boosted by 8.9%
    • Input voltages below 102V are boosted by 18.8%
    • Network grade AC surge suppression

    I was looking at this one on Monoprice yesterday for $109 and thats not even their sale price(they put everything on sale ever other month or so). Does it look the same too you? Its hard to tell with the specs listed on the site.
     
    Last edited: Aug 19, 2019
  2. Exojam

    Exojam Well-Known Member

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    The Equitech’s I have in the guitar room we’re picked up off of Reverb in a non working state. One I fixed for 35 bucks, the other one I fixed for about 75 bucks. Each one I purchased from Reverb were for 75 bucks each including shipping.

    Now in my family room I purchased years ago, two 2Kva “transformers in a box” they were selling a “blem” unit’s each one for 500 bucks. I had an electrician come over and wire them into my 100 amp sub panel in the basement and ran the wiring up to some outlets for me.

    You can see there prices from the link below. They just come in a NEMA 12 enclosure and you can if you wish, wire up outlets right in the cabinet and hook up a plug for the wall.

    https://www.equitech.com/productsold/isolation-transformers/#
     
  3. Michael Inglis

    Michael Inglis Active Member

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    No shit? Thats a great deal and i can fix most things, im no electrician but ive been building my own pedals and troubleshooting electronics for years. Something else to think about i guess.
     
  4. Exojam

    Exojam Well-Known Member

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  5. Exojam

    Exojam Well-Known Member

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    I go not gig, no where good enough for that.

    I had also looked at the voltage unit Angus runs in his setup. They are very nice but of coarse they are not cheap but it allows his techs to dial in and keep stable the voltages he needs where ever he tours.
     
  6. grainman

    grainman Well-Known Member

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    back then when rock n roll was something bigger than wall mart today...guitar players never heard a thing about biasing their amp and it was during these days tube amps were kings of the stable...so do you think we are over doing things just because theoricaly we have to.??...I never heard of a tube amplifier blowing caus the bias was a notch off..maybe red plating once every blue moon ..but then, you fix your bias...... .every time I change my power tubes ?! maybe not....
     
  7. mickeydg5

    mickeydg5 Well-Known Member VIP Member

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    His VAC at the wall was 100VAC, nowhere near normal. That means instead of 450VDC at the plates he had more like 380VDC and was trying to just bias by idle current.

    That is not ideal.
     
    Lance Chambers likes this.
  8. ampeq

    ampeq Well-Known Member

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    Back when I got into guitars and learned I liked tube amps best, I never even heard about biasing an amp. I’v had all kinds of amps and not once did I do it. About 10 years ago I learned about it and started checking them. I haven’t had a Fender or Marshall in a long time, but my Mesas and Carvins have been spot on. The only one I tweaked was my new X100B when I put 6L6’s in just to try them and then back to EL34’s. I’v always used Groove Tubes and they are very close to each other though.
     
    grainman likes this.

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