Building 12" External Cab. for Vintage SF Champ: What Dimensions?

Discussion in 'Amp Tech Center' started by jeffv, Nov 7, 2016.

  1. jeffv

    jeffv TDPRI Member

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    Hi, I'm seeking advice on cabinet size, material and close vs. open back for a 12 inch external cabinet to to plug in my silverface Fender Champ. The speaker I have is a 12" EV speaker that came in an old Musicman amp I bought. The magnet is so large that it was butted up against the tubes in the MM 65 112. The Champ has a replacement 10" Weber which sounds great, I'm curious to see what a 12" cab would sound like. Also, what's the difference in sound between running the Champ thru a 112 vs a 212 cabinet?
    Thanks in advance, Jeff Charlottesville
     
  2. mRtINY

    mRtINY Tele-Afflicted

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    2x12 will have more bass and it will be beamier (highs only in straight out).

    I'm gonna guess that that EV is a bit thin sounding in an open-back cabinet. What model is it?
     
  3. jtcnj

    jtcnj Tele-Holic

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    You could copy existing:

    The Fender Super-Champ 112 1x12 Guitar Speaker Cabinet mates perfectly with the Super Champ X2 Head or other quality amplifier. Made in Ensenada, Mexico, it's compact and rugged; rated at 80 watts RMS (at 8 ohms) and features a single 12" Celestion G12P-80 speaker for tight, defined tone and a closed-back design for increased bass response.

    FEATURES
    • Powerful Celestion speaker
    • Compact and rugged construction
    Get the most from your Super Champ head. Order today.

    SPECIFICATIONS
    Super-Champ 112 1x12 Guitar Speaker Cabinet

    • Speaker: 12" Celestion G12P-80 Speaker
      Impedance: 8 Ohms
      Height: 17" (43.2 cm)
      Width: 17.5" (44.5 cm)
      Depth: 9.156" (23.3 cm)
      Weight: 28 lbs. (12.7 kg)
      Unique Features: Celestion G12P-80 Speaker for tight, defined tone, 80 Watt RMS power handling, 8 Ohm impedance, Closed back for increased bass response
     
  4. jeffv

    jeffv TDPRI Member

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    Thanks for the feedback. The EV speaker (I was told it is an EV) has a sticker on the magnet that says "Electric Ladyland" Louisville. The magnet is massive, the thing is really heavy, paper cone. Not sure what model
     
  5. jeffv

    jeffv TDPRI Member

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    One other question-- will the head have to work too hard if I run from the 4 ohm out on the head to an 8 ohm 12" speaker?
     
  6. mRtINY

    mRtINY Tele-Afflicted

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    You should be fine with that mismatch. It may change the tone a bit.

    As to the size and bass output - do a sealed cabinet first. If you find you want more bass output, you can add a port later. With actual guitar speakers, there's really no design work except the box and port dimensions to get the frequency you want (usually somewhere between 60 and 80 Hz).

    Sometimes, with more compliant drivers (mid-woofers) there's some interaction between the driver rolloff and the port. But, for guitar, if it sounds good, it's good. It's just that you don't have extensive tone controls on the Champ. So, the basic voicing has to be where you want it ...
     
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