Jensen MOD speakers

Discussion in 'Amps [BG]' started by xander8280, May 22, 2012.


  1. xander8280

    xander8280

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    Anybody use these? Good for bass? I like vintage Jensen speakers, will these MOD speakers work good for bass? Sound good?
  2. JimmyM

    JimmyM Supporting Member

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    It's possible. I know some folks who use the 32 ohm Jensen Mod 50's to brighten up the 810e's that have unusually dark speakers (2000-2006). But it cuts down on power handling, so that's the tradeoff. They don't have a lot of power handling, and in some cases, the cab design will actually cut down on their power handling and overall usefulness for bass. It's definitely a case by case basis if they'll work for you.
  3. billfitzmaurice

    billfitzmaurice

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    Not by themselves, except at bedroom volume levels. They're guitar drivers.
  4. xander8280

    xander8280

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    If I got four of them that are rated at 110 watts a piece do you think I could achieve better results?
  5. billfitzmaurice

    billfitzmaurice

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    Wattage ratings are meaningless. Output is limited by driver displacement. The displacement of the Mod 10-50 is 50cc. That's one-third that of a good bass ten. To get the low end output of a good 410 you'll need twelve Mod 10-50s.
  6. BurningSkies

    BurningSkies

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    Now you go and say that, all the TB kids will be cobbling together their 8x12 cabinets.
  7. christw

    christw Get low!

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    I'm going to go build a 10x12 Mod bad cab for my highs and a 6x15 cab for lows. :ninja:














    ;)
  8. xander8280

    xander8280

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    By the power handling being weak are we talking that they fart on yah when you turn it up too high? Or just don't get any louder
  9. BurningSkies

    BurningSkies

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    Distortion will set in fairly quickly, especially if lows are applied...and if the xmax is low, the xlim will also be fairly low, meaning mechanical harm to the drivers.
  10. Mr. Foxen

    Mr. Foxen

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    Bear in mind that lows aren't essential to a good bass sound, depending on context, but it will be a pretty guitary bass sound. Or if you have lots, it will be like using the old SVT cabs, squareback type.
  11. xander8280

    xander8280

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    Wouldn't porting a cab/tuning it help with the displaced volume? I mean, I wouldn't stick a bunch or holes in the cabinet; but a vent hole in the center of the 4 drivers might help. I'll experiment. I need the cab to be able to handle 250 watts from my head and the volume won't be dimed. Most likely around one or two volume. I never need to go louder.
  12. billfitzmaurice

    billfitzmaurice

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    Not necessarily. Bass drivers tend to have around a 2:1 xlim to xmax ratio, because they have high xmax. Guitar drivers tend to have 4:1 or higher xlim to xmax ratios, because the xmax is so small. This means that guitar drivers can withstand a lot more overshoot, because they're intended to be driven into heavy clipping, bass drivers are not.
    Both.
  13. xander8280

    xander8280

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    What's a good bass drivers Xmax?
  14. Mr. Foxen

    Mr. Foxen

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    Speakers aren't really suited to a vented enclosure, just make it a bunch easier to tear them up. The air pressure of a sealed cab will make their survival much easier.
  15. billfitzmaurice

    billfitzmaurice

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    4.5mm

    Forget about watts. They do not define output. Speaker frequency response, sensitivity and displacement do.
  16. BbbyBld

    BbbyBld

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    I agree with you, except that specs-wise, they are nothing like the square magnet SVT speakers I had. I bought a vintage SVT 810 with some blown speakers and I ran specs on the remaining good ones. I then looked at the MOD speakers because they were supposed to be good replacements, but I did not use them because they did not seem to be on paper. They may work just fine, but I wanted a more authentic sound.

    In case anyone is interested, here are the specs. I measured from a 1978 SVT square magnet Eminence speaker for comparison purposes:

    Qts=0.919
    Qms=3.775
    Qes=1.215
    Vas=1.568 cu. ft.
    Fs=59.37Hz
    SPL=90.87(funny...I figured this would be higher)
    Z=40 ohms
    DCR=26.1 ohms
  17. Mr. Foxen

    Mr. Foxen

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    Were you comparing 30 year old used speakers with new MOD ones?
  18. xander8280

    xander8280

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    Yes, I like the power handling of old jensens with bass. I was thinking maybe these new MOD's are like the classic tuck n roll jensens that could do guitar AND BASS. LOL, thanks for all the replies guys. Much thanks. I need to get back into my physics studying and learn my stuff.
  19. billfitzmaurice

    billfitzmaurice

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    Mod 10-50 fs is 109Hz, so right there you've got an octave lost with them. Even the C12Ns used by Fender and others (as in my '65 Bassman) have a 112Hz fs and 1mm xmax. Today we wouldn't consider them for a moment for electric bass.
  20. BbbyBld

    BbbyBld

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    Again, I went by specs alone. I never listened to the MODs. Obviously, mine were broken in, but I would hope that Jensen breaks in speakers before THEY list specs.

    At any rate, I was able to obtain a 32 ohm 70's Eminence spec. of unknown vintage. Speakers can vary a lot. For comparison purposes:

    Qts=0.449
    Qms=7.361
    Qes=0.478
    SPL=93.30
    Vas=2.017 cu. ft.

    ...and that's all I have.

    I'm not telling anyone not to buy the MODs. I'm saying that I don't think they are an authentic replacement going by specs alone. On the other hand, I believe that Electro-Harmonix makes a replacement speaker, and I remember the specs. on that one looking A LOT closer.

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