Hayseed 30 JMI mod ?

Discussion in 'Amps and Cabs' started by 69strat, Jun 10, 2006.


  1. 69strat

    69strat Member

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    Can someone email me the latest JMI mod? I have tried the first mod and want to update it to the present mod. Thanks. I love this amp!!!! Also, has anyone tried the new tungsol 12ax7,s in there?
     
  2. TwinandTwang

    TwinandTwang Member

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    Could I get a copy as well?

    TIA
     
  3. bscepter

    bscepter Member

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    I use the Tung Sol 12AX7s in my Hayseed. They sound great for what I'm doing (basically, turning the b@stard up all the way!). These days, though, I've been using a Telefunken EF86 instead, which makes it beefier and richer.
     
  4. 69strat

    69strat Member

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    Yea I agree, the telefunken ef86 is beefier. I have the stock jj 12ax7,s in there and have heard that the new tungsols are the bomb! Me and my endless tweaking!!!! My wife now calls me tweaky!!!!:moon
     
  5. The Pup

    The Pup Supporting Member

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    Update:

    Rob, the ever mad scientist, has a new cut control mod/variation to further explore the Heyboer equipped Hayseed's tonal possibilities. The mod sounds great and helps to better replicate the early '60's vintage sound...taming the Heyboer's prodigious bass and beyond vintage bandwidth (which is very cool in its own right).
    [​IMG]
    This is a cool one! Let's call it: the "Cut Super Mod!" ...for now.

    With all of these mods, I've got $4.00 in parts and 20 minutes of my time invested. This amp is so easy to mod and it's a blast shaping the tone of my amp to that of my desire.

    As you can see...just remove a few screws and you can play around to your heart's content.

    Note: None of these mods are necessary or essential...I'm just having fun and making the amp extremely versatile for my growing stable of guitars.

    What a beautiful sounding amp!

    Tonight was the Jazzmaster, Duo Jet and the ES-335 with the amp set at:

    MV: 1/3 (2/3 attenuated)
    Power Sw: 1/2 (15w mode)
    Filter SW: 16uf
    Mode SW: EF86 Bright (TB)
    Reverb: 1/3
    TB Gain: 11:30
    HI: 12:00
    LO: 12:00
    Cut: Full CCW
    Tremolo: Speed 10:00, Depth: 11:30

    Very lush and inviting...impossible to stop and say goodnight.

    Earlier today, with the SG and the EF86 gain full on (Cut set at 12:00), I was able to get a phenomenal distortion sound using this cheap Svetlana tube EF86:
    [​IMG]
    It really hit the spot. Very tasty indeed!
     
  6. The Pup

    The Pup Supporting Member

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    Did another EF86 Tube taste test this weekend with the following tubes from my home spares stash (pulled used, but all very good and all completely non-microphonic):
    [​IMG]
    [​IMG]
    Amperex, Mullard (a few different types), TFKN, Valvo and Svetlana Winged "C."

    Each tube has its merits and I must admit you really cannot go wrong with any of them. If I could have a lifetime supply of just one of the above, it would be the Valvo by a thin margin over the rest (although I found it almost impossible to keep them straight in my head after a few swaps back and forth). Dimed, the Valvo even beat my current favorite: the Svetlana Winged "C."

    The Valvo had a nice breathing/squishy crunch that was quite surprisingly pleasant even with my highest output humbuckers. I also found the Amperex and the black labeled Mullard similar but not as much grind at full throttle. The TFKN was quite sweet at 1:00 (gain setting), but lost a small degree of focus at full CW gain. The Svetlana was not as sweet and focused at moderate gain settings but really shined full-on.

    Disclaimer: I am not an EF86 expert by any measure, so I wouldn't be surprised if a few of these tubes were manufactured at the same plant and relabeled for sale.Note: Obviously tested with the Hayseed (EF86 Normal and Brilliant selected). If you want a good sounding EF86 for cheap (as of today), get some of those Svetlana Winged "C" tubes (no longer in production but plentiful
     
  7. tralfax19645

    tralfax19645 Member

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    Hi,
    I would hold off doing any of these mods to the amps. E mail me if you have any questions,
    rob
     
  8. Tapp

    Tapp Member

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    Pup,

    Do you have any solid plate EF86's in your stash? I've got a GE labeled solid plate in my Vox AC30 (with an add-on EF86 channel). The GE sounds good. I'm wondering if the solid plates are better as far as microphonics? I hear slight ringing when I crank this channel.

    Tapp
     
  9. The Pup

    The Pup Supporting Member

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    OK...I'll play.

    Why?

    Is it because you need to ensure the given amp's configuration is correct for this mod (e.g. Hayboer vs. MM)? Or, do you have yet another mod coming around the corner?
     
  10. The Pup

    The Pup Supporting Member

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    The "solid plate" TFKNs are prone to squeal at the highest gain settings. But, they do sound very good at moderate gain levels. I'm afraid I don't have a GE on hand. I have a hoard of tubes that I keep in a storage facility for insurance reasons...the prices for these NOS tubes have gone through the roof (well beyond any reasoned cost-to-benefit ratio in my opinion).
     
  11. The Pup

    The Pup Supporting Member

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    This JMI mod is very cool.

    Sounds as advertised...this is awesome with the Heyboer!

    [​IMG]
     
  12. adelphi710

    adelphi710 Member

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    what if you have a mercury OT, is the mod necessary?
     
  13. tralfax19645

    tralfax19645 Member

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    Hi,
    This is NOT for the mercury equipped amps. They are just perfect as is.
    Rob
     

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