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Upgrade speaker for Polytone Minibrute

Discussion in 'Amps and Cabs [BG]' started by Chris Fitzgerald, Mar 31, 2006.


  1. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    I'm all set for my gigging rigs, but for my rehearsal space, I have Minibrute 12 from roughly the Jurassic period - black velvet and all. The speaker isn't the cleanest thing in the world but it does OK for the low volume stuff I need for rehearsals. Is there a better speaker that would fit in a cab that size that would be a noticable upgrade in terms of tightness and "clean" sound? It's not a big deal, but I'm spoiled by my gigging amps and the flabbiness of this ancient driver is mildly annoying at times.
     
  2. Nighttrain1127

    Nighttrain1127 Supporting Member

    Nov 27, 2004
    Near Worcester MA
    You could always disconect the speaker output wires from the polytone and hook them up to a 1/4" jack and play through any speaker cab you want to.
     
  3. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    Wow. No-one knows of a replacement speaker for this amp??
     
  4. B String

    B String Supporting Member

    Apr 11, 2002
    Los Angeles
    When I needed a replacement speaker years ago, I found
    out that Polytone uses a very specialized speaker.
    Something like 3 ohms, very shallow from front to back,
    and made for a sealed box. I think a foam surround is
    used. So.... If the jerky lady who answers the phone
    doesn't want to sell you a speaker, you're out of luck.
    I don't know if they still used the same speaker in the
    new amps. I finally took out all of the bown guts, sealed
    up the box, found a cheap speaker that would even fit in
    the box, and now its just a throw around "don't worry about
    it" box. Things may have changed, but dealing with
    Polytone repairs has traditionally been like a root canal.
    Good luck.
     
  5. chadds

    chadds

    Mar 18, 2000
    A JBL K-120 or D120 will not fit cab's to shallow. I tried.
     
  6. zombywoof5050

    zombywoof5050

    Dec 20, 2001
    I wouldn't worry about trying to find a 3 ohm speaker. I had a Polytone S15B (15" speaker plus 2 horns) in which I replaced the speaker with an 8 ohm EVM15L, and it worked fine with no loss in volume. I'd say as long as you can find a speaker that will fit it should be fine, just don't go less than 3 ohms.
     
  7. Ed Fuqua

    Ed Fuqua

    Dec 13, 1999
    NYC
    Chuck Sher publishes my book, WALKING BASSICS:The Fundamentals of Jazz Bass Playing.
    I put a JBL in my Polytone extension cabinet, but I had to get a buddy of mine with a woodshop help reconfiguring the opening AND come up with a way to attach it. NOT happening.
     
  8. Lia_G

    Lia_G

    Oct 27, 2005
    Heya, Chris,

    I have an old Polytone Teeny Brute (60 or 90 watts into a 10"), and recently had a local shop replace the speaker and all the capacitors. The thing is just amazing now. They used an Eminence of some sort, a Delta, I think.

    The little amp still looks cruddy / funky, but the sound is amazing. Unfortunately, a drummer friend of mine has borrowed it so he can play bass along with his drum students.

    So, although my amp's a different model, and a 10 rather than a 12, you might check out Eminence's speakers ...

    Good luck!

    Liam (originally from near Paducah, with a sister in Elizabethtown ...)
     
  9. Basshole

    Basshole Banned

    Jan 28, 2005
    Chris,

    I have a Mini Brute I, and when the speaker kicked, to be honest, I didn't even look at the OHM rating. I just ordered an EV 12" and stuck it in there.

    That was over a decade ago, and I've had zero problems. Sounds much better than the stocker

    I also replaced the foam grill with a piece of expanded steel mesh (the killer industrial kind, that you can actually stand on), and the little thing is bullet proof. I think I had to replace the output transistors once in the 25 years I've owned it.

    Sits in my living room now, as my noodling amp.

    Good luck...great little amp.
     
  10. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    I like the idea of an EV 12" replacement, and have no idea about the capacitors...how invasive is this, and could a local guy do it in all likelihood?

    As regards the speaker, the only thing I would want to be sure of is, "will it physically fit" in the box? I wonder if Polytone has any specs for boxes that old? I'd hate to order speaker after speaker only to find that they were all too big to cram into the cabinet!
     
  11. B String

    B String Supporting Member

    Apr 11, 2002
    Los Angeles
    Please excuse my 3rd grade reading ability. I didn't realize
    you were asking about a 12in speaker. My Polytone was a
    MiniBrute with a 15in speaker. oops
     
  12. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    Still in the same boat - this thing is getting pretty farty! I'm gonna start by popping an Eminence in there and seeing what happens. It's an office/school amp kinda thang, and I like just taking the cube around to rehearsals. Hopefully, a generic Eminence will work. Unless anybody has any last minute upgrade suggestions....?
     
  13. robgrow

    robgrow Supporting Member

    May 1, 2004
    Cincinnati, Ohio
    Chris, try an Eminence S2012. It will be an upgrade to the original speaker and will work OK in a small sealed box. It also uses a neodymium magnet, so it's very light. You can get them from a number of sources including Parts Express.

    BTW there's nothing special about the original speaker. Polytone used pretty generic, low-cost drivers.
     
  14. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    Rob - that looks good as long as it will fit. One thing, though: weight isn't an issue with this box, as I usually wheel it wherever it needs to go and it stays in the same building. Given this, is this still the speaker you would recommend?
     
  15. Jazzdogg

    Jazzdogg Less barking, more wagging!

    Jul 29, 2006
    San Diego, CA
    Amen! I have an old MiniBruteIII (15"), and although it still sees use for practice and the occasional rehearsal or trio gig, I abhor dealing with Polytone: absolutely the worst customer service I've ever experienced.

    As to your original question, Chris, you might want to see if a local speaker shop can do a re-cone. I had mine re-coned 10 or 15 years ago, and I haven't had a problem since.
     
  16. robgrow

    robgrow Supporting Member

    May 1, 2004
    Cincinnati, Ohio
    Yes, I'd still recommend it. Since the basket on the S2012 is the same size as the original speaker, it will fit just fine. It's a direct replacement with no modifications necessary. The only difference is the S2012 is a better speaker than the original with a higher sensitivity rating, so the amp will seem louder for the same volume settings.

    According to Eminence, the original cone for these speakers is no longer available, so anyone reconing one of these drivers would have to use a generic replacement kit. Also reconing is usually not cheap these days, so it just makes more sense to get a new, higher-quality speaker. There's nothing special about the original driver.
     
  17. staccatogrowl

    staccatogrowl Savoring time on a spinning, shimmery, aqua sphere Supporting Member

    Jul 14, 2006
    Replaced my stock Polytone speaker with an Eminence 8-ohm Legend. Beautiful, reliable tone. Never looked back.

    Polytone power ratings are at 4-ohms, and the stock speaker may be 4ohms. However, my belief is that the Legend is more efficient. There is no appreciable volume loss.

    Need more volume? Use an extension cab or run signal to PA.
     
  18. jruberto

    jruberto

    Dec 23, 2008
    Denver, CO
    Staff Producer / Audio Engineer: Blue Tower Studio, Denver, CO & Mighty Fine Productions, Denver, CO
    Ressurecting this old thread hoping to find some info.. I have my Taurus III in the shop and my amp tech is having trouble shaking down a schematic for the power amp board.

    Any leads on a source? I spoke w/polytone & they weren't super helpful. Internet searches reveal very little about this amp, apparently it's pretty rare. Greaaat.

    Thank you! Cheers, j
     

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