Tube Choice for Art Tube Pac

Discussion in 'Amps and Cabs [BG]' started by Mad Tango, Dec 10, 2007.

  1. Mad Tango

    Mad Tango

    Apr 18, 2006
    Pearland, Tx.
    I have heard that my Art Tube Pac (intended use for tube warmth then sent to a Radial JDI for Xfrmer ISO for house mix) would sound better if I replaced the stock tubes. The stock two tubes are said to be cheap 12AX7's. I have read that for bass medium gain 12AU7's are better for more dynamics and better bass resonce. Is this true and if so, can someone recommend a brand that they have actually used? It sounds OK to me now, however; if I can get a better sound I will do it. Price range $50 max. for both tubes.
  2. vicenzajay

    vicenzajay Supporting Member

    Dec 21, 2004
    Christiansburg, VA
    For one, check what tubes are actually in your unit. My two came with a very nice EH 12AX7 in the driver slot and a Philips 12AT7 in the compressor tube slot - those were stock and very nice tubes. Both of mine came well equipped, so you might not need to upgrade.

    For two - the TubePac makes an excellent active DI box on its own - please try it before spending more money on another DI.

    just my .02
  3. Mad Tango

    Mad Tango

    Apr 18, 2006
    Pearland, Tx.
    Thanks Jay,
    I will look and see what tubes are inside. I already have the JDI and wanted to add a bit of warmth. Also, our Allen & Heath mixer fried the DI section in my Hartke Attack pedal w/phantom power. This why I do not want run the active type Art Pac to the mixer alone (don't want another mishap). With a passive DI, you have the isolation of a transformer in the JDI which will completely block the D.C. voltage.
    I hear thats a major disadvantage of the good sounding Avalon U5 is that it can be toasted by the 48 d.c. volts of a mixer. Talk is that they refuse to add protection in their product.

  4. A9X

    A9X Inactive

    Dec 27, 2003
    No. A 12AU7 is NOT a sub for a 12AX7.
  5. 4Mal

    4Mal Gold Supporting Member

    Jun 2, 2002
    Columbia River Gorge
    Tube swaping in one of those or it's siblings the Tube EQ or Tube Channel - doesn't make a lot of difference. They are great unit's but their forte' is in sounding clear and crystal - not tubey ... I swapped in some middle of the road JJ's and then a NOS Mullard and NOS RCA - damn'ed if I could hear a whit of difference ... In my Alembic - those tubes all showed significantly different character...
  6. Mad Tango

    Mad Tango

    Apr 18, 2006
    Pearland, Tx.
    Both of you are right, I talked to the guy at Tube Depot and he said that a 12AU7 only has approx. 20% of the gain of a
    12AX7. He also suggested I put a medium quality tubes for upgrade in this unit. He recommend Tung-Sol 12AX7 for my Art Tube Pac.
  7. bongomania

    bongomania Supporting Member Commercial User

    Oct 17, 2005
    PDX, OR
    owner, OVNIFX and OVNILabs
    Another good option- on Ebay there's a couple of sellers with stock of Sovtek 12AX7LPS tubes which are very low-noise and a great bang per buck.