tubes for Fargen Mini-plex

Discussion in 'Amps and Cabs' started by Uli Jon Blackmore, Feb 25, 2012.

  1. Uli Jon Blackmore

    Uli Jon Blackmore Supporting Member

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    I have always hated JJ 12ax7s in all of my previous amps (Marshall 401, PV 5150, bumbox lead 1, 100wt 1978 Marshall JMP, AC15, Tiny Terror, Marshall Vintage Modern (still own) so I thought that I would retube my wonderful mini-plex with something other than the installed JJs. I put in my fav current production brand Tung-sol and the amp sounded bad, raw, tinny, just wrong. I loved the tung-sols in other amps. Perhaps Ben voiced the Mini to deal with the muddy nature of the JJs (yes, I know some of you love them, but I have always been flabbergasted by that, up until this amp, I thought that they sounded like someone burred my amp under a mud puddle)

    For those few who have the Mini-plex, what 12ax7's sound best to you?
     
  2. lang.murphy

    lang.murphy Member

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    Don't have a MiniPLEX myself, but if the JJ's sound better than the Tung-Sols... well... leave the JJ's in, I guess. Got any other pre's you can throw in there, just for fun?

    You can mix/match power tubes in that amp, right? Say an EL34 and a KT66? I was thinking last night... one could roll dif EL34's... Say a Mullard RI and a Siemens... that sounds like a fun amp, bro.
     
  3. Uli Jon Blackmore

    Uli Jon Blackmore Supporting Member

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    The amp IS a tone monster. There is an interesting story about tubes for me. My parents are retired and do estate sales for extra income (they were in the antique business) Last month they told me that the oversaw an estate sale for an old radio repairman and have many, many boxes of unused (NIB) tubes from the 60s for me. My father assures me that at least some of them are 12ax7s. They are shipping the whole lot to me. IF it turns out that these are amp related tubes I will take some pictures just to make TGPers salivate.

    I do have some 66s around that I need to try in the Mini-plex. I have been waiting for an el34 amp for long enough that I have not experimented along those lines as of yet (my Vintage Modern has 66s) I fully expect to try out a lot of options but am really blown away by the tone from the JJs in this thing.
     
    Last edited: Feb 25, 2012
  4. lang.murphy

    lang.murphy Member

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    Not for nothing... but Joe Morgan rolls, or did roll, JJ's in his amps. (At least in the DAG15 I had...) So Fargen ain't the only bod rolling JJ's these days. I think there might even have been a JJ or two in my Marshall C5 head that I had briefly a few months ago... but can't recall clearly. I do recall that Mr. Morgan was fairly emphatic that I leave the JJ's in the amp, as opposed to rolling Mullard pulls from a 60's Vox.

    In any event... remember who first responded to your post when you get that shipment of NOS 12AX7's in... ;-)
     
  5. Tonesmiths

    Tonesmiths Member

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    Here's my preference for a MP MkI. A Sylvania greyplate 12AX7 (Ken Fisher's fav) feeding into a JJ 6L6 on one side and a Ruby 12AX7-HG feeding into a Valve Arts KT66 on the other. After tons of tube pairings that's the one that had the Magic. The 6L6 side is big & round and the KT66 side is all grind and chime. I have two friends with MkIs and, after hearing mine, that's what they're running now.
     
  6. TheGuildedAge

    TheGuildedAge Member

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    I us two Siemens EL34s in mine, with an Amperex in V1 and an RFT in V2.
     
  7. aynirar27

    aynirar27 All You Need Is Rock and Roll Gold Supporting Member

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    Listen to the guys from PA, close to the guy above i put an RFT in V1 and an Amperex in V2. you are right that the amps get very thin with some 12ax7s. one el34 and one kt66 in the power section adds a little umph as well, or 2 kt's if you really want it thicker
     
  8. Uli Jon Blackmore

    Uli Jon Blackmore Supporting Member

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    Thanks all. I will be trying any/all of the NOS tubes when they arrive and probably be purchasing your suggestions. I do want to make clear, though, the amp is glorious and I love it with its original tubes. If tube changes create no improvement, I will still adore the sounds out of this amp.
     
  9. larsjen

    larsjen Supporting Member

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    Great suggestion! I put in this mix and like it much better others I tried.
     
    Tonesmiths likes this.

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