1. Fishin'Musician

    Fishin'Musician Silver Supporting Member

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    I have a Fuchs modded Bandmaster with both 4 and 8 ohm outputs. I have an 8 ohm Tonespotter in there, and I have an extension cab I plan to put another 8 ohm speaker in. How should I wire this up? Should I install a jack on the lower panel of the combo and just run the wires from the extra tabs on the tonespotter to the jack? Is this parallel? What would my impedance be and so forth?
     
  2. mbratch

    mbratch Member

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    Does the internal speaker use the 8 ohm output you are referring to?
    Are the 4 and 8 ohm outputs independent of the internal 8 ohm connection, or are they in parallel in the circuit?

    My amp has an internal 8 ohm speaker, an extension speaker jack, and a 4 / 8 ohm switch. If I connect an external 8 ohm speaker, I set the switch to 4 ohms because the external and internal speakers are in parallel, and 2 x 8 ohms in parallel is 4 ohms. I have another amp that has an independent external speaker jack that is set for 16 ohms and is unaffected by any other speakers being attached.

    And, yes, if you run a pair of wires off of your internal speaker terminals to the external cab, that's parallel. If both speakers are 8 ohms, then in parallel they'd be 4. The formula for parallel is
    (1/R) = (1/R1) + (1/R2), or
    R = (R1xR2)/(R1 + R2)
     
  3. Fishin'Musician

    Fishin'Musician Silver Supporting Member

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    Cool, so I'll just run out of the 4 ohm jack down to the speaker, then jumpered across to the jack. --> To the ext cab.
    Thanks!
     
  4. VintageJon

    VintageJon Member

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    What on the world is a ToneSpotter???

    -Jon
     
  5. RussB

    RussB low rent hobbyist Silver Supporting Member

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    Hi Jon,

    It's one of the many new speakers that Eminence has released...They're building some good speakers over there in Kentucky!

    (note to self...I need more surf bugs!)
     

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