Aligning Screw Holes For New Speaker

Discussion in 'Amp Central Station' started by JayFreddy, Oct 18, 2019.

  1. JayFreddy

    JayFreddy Poster Extraordinaire

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    I recently replaced the original Utah 12" in my 1974 Deluxe Reverb with a new Eminence George Allesandro SC64 12".

    It came out great, but it was much more difficult than I expected. I'm hoping that sharing my experience here will help others.

    First off, the placement of the screws in the baffle board did not line up with holes in the new speaker basket.

    The new speaker basket is signficantly larger than the one for the old Utah speaker. I don't think this is just Eminence. I think most modern speaker baskets are slightly larger.

    Rather than damage the new speaker basket, we decided to remove the screws and redrill the screw holes in the baffle to accomodate the new speaker.

    This required a late night run to Home Depot to buy an extra long drill bit... Thank God for extended hours!

    When removing the speaker basket screws from the baffle board, I noticed that 2 of the 8 screws were significantly shorter than the rest. These are the screws for the bottom of the speaker basket.

    These short screws leave room for the reverb tank. Who knew?! I bet Wally knew, but I sure didn't! LOL :lol:

    Replacing the speaker required the following steps:

    1) Remove all wires from chassis

    2) Remove the entire chassis from the cabinet, including unbolting the cable clips for the AC cord.

    3) Remove reverb tank from cabinet

    4) Remove the old speaker

    5) Remove the grill cloth (it was just velcro'd on)

    6) Remove the speaker basket screws

    7) Trace the new speaker holes onto the baffle to make sure that the new holes would line up correctly

    8) Drill new holes in the baffle and remount the basket screws, remembering to countersink the heads into the front of the baffle

    9) Camoflage the old holes with black marker

    10) Bolt in the new speaker

    11) Return chassis to cabinet

    12) Return reverb tank to cabinet

    After we got the chassis back in the cabinet, that's when we noticed that two of the screws were shorter... Doh! LOL o_O

    Luckily we didn't need to remove the chassis again, but it was close... Now I know! :lol:

    After we returned the short screws to their correct positions near the reverb tank, we remounted the back panels and the grill.

    I was ready to throw in the towel and hire a professional, but my friend who was helping me was more resourceful than I am and he made sure it got done right!

    (Thanks Ted! :cool:)

    Hope this saves a few headaches out there!
     
    Last edited: Oct 18, 2019
  2. gridlock

    gridlock Friend of Leo's

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    I’ve put two of the same speakers in two different BF Deluxe Reverbs and the screw holes lined up perfectly. No drilling etc. required using the same originally installed screws. Of course, I also had to remove the chassis and Reverb pans foe clearance to install the speaker. One transformer is the main obstacle to clear.

    The GASC64/was designed to be a Deluxe Reverb replacement. I don’t understand why an SF Deluxe would be different than a BF Deluxe screw pattern wise?
     
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  3. D_Malone

    D_Malone Tele-Meister

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    I know you said you didn’t want to damage the new speaker basket, but couldn’t you have just enlarged the holes a bit? Would have been a hell of a lot easier.
    I’ve had to do it on occasion. Not a big deal.
    You’ve gone to great trouble to alter your valuable amp instead of performing a minor alteration to your relatively inexpensive speaker.
     
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  4. JayFreddy

    JayFreddy Poster Extraordinaire

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    Are your BFDRs original or reissues? Were the original speakers in yours Utahs?

    I thought long and hard about this.

    When i initially realized that "something will have to give", my first instinct was to alter the new speaker, and not the baffle board...

    After a little bit of thought and I decided that new holes in the baffle were less likely to affect performance.

    I think you could go either way on this, but maintaining structural integrity of the speaker was the way I chose.

    It made more sense to me to move the screws... And wood is easier to drill than metal.

    The baffle board is a simple piece of chip board. I don't believe that adding the new holes (and carefully camouflaging the old ones) detracts from the value of the amp, at least not as a player. If i wanted to keep it original, I could have just reconed the original Utah.

    This particular amp spent its first 20 years unopened in its original factory shipping box. It was removed from the box for the first time in 1994, and then spent the next 25 years in a climate controlled and dust free recording studio.

    I seriously considered keeping it completely original, as the electrolytics all tested strong and good. Since I bought this amp to use, I replaced the caps and other electrolytics anyway, just to be safe.

    The new GA speaker is a noticeable improvement over the little Utah which would "flub out" at higher volume levels... The Utah wasn't designed to handle that much bass.

    When I first realized that the speaker wasn't going to fit without some modification, I went straight to Professor Google for answers...

    That's the main reason I created this thread. If I had found this thread in the beginning, I would have been much better prepared.
     
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  5. gridlock

    gridlock Friend of Leo's

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    Both are original vintage 1965 Fender Deluxe Reverbs.

    BFE4C06F-949E-4562-9D48-40B491A146B5.jpeg I 2950E764-E213-41D1-A612-910932C0EB4D.jpeg
     
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  6. JayFreddy

    JayFreddy Poster Extraordinaire

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    So I guess they aren't equipped with Utah speakers.

    The spacing of the Utah was different from the Eminence by nearly an entire centimeter.
     
  7. gridlock

    gridlock Friend of Leo's

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    Both of my Bf Deluxe’s had Oxford’s originally. I did own a ‘72 Twin Reverb that I swapped the original Utah’s with Jensen RI’s and I recall it being a direct swap.
     
  8. JayFreddy

    JayFreddy Poster Extraordinaire

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    Well, I guess I should have taken pics to prove that it wasn't a direct swap.

    No matter, there are several other threads out there on other forums with people who had the exact same problem as I did.

    None of them break it down step by step.

    I have changed a half dozen other speakers in different amps and never had this problem.

    That's part of why I was so surprised... And also why I created this thread!

    Ps. The George Allesandro is a very nice speaker for the Deluxe Reverb. Not only is the the bass nice and tight, it's significantly louder too.
     
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  9. gridlock

    gridlock Friend of Leo's

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    Not doubting you. I just never ran across this and I’ve owned three SFDR’s and two BFDR and I think that I’ve sapped speakers in all but one of them.

    I agree, the Alessandro is a great speaker right out of the box. It sounds great low and loud (no flub) and adds low end bass that I feel these amps sometimes lack.
     
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  10. Dan Skammer

    Dan Skammer TDPRI Member

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    I had a similar problem with the 12" Alessandro GA SC-64 speaker ,I removed the stock Jensen C12Q from my '64 Custom Deluxe Reverb HW to install the SC64 , I could only get 3 bolts in the baffle....it's been that way for a probably a year already.
     
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  11. schmee

    schmee Poster Extraordinaire

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    I have had matching issues but not a lot in my BFDR's and SFDR's. Some early Weber speakers would barely fit the studs. I have NEVER had to redo the stud locations.
    What I found is the studs sometimes are bent just a little from perpendicular to the baffle board. A little makes a lot of difference. Minor tweaking with some sturdy pliers ALWAYs got the speaker to fit.
    I currently have the GA SC in 3 vintage Fender amps with no fitment issues.
     
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  12. zombiwoof

    zombiwoof Tele-Afflicted

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    I have had that problem where the speaker gasket extended halfway over the mounting holes, it made it seem like the spacing was off. All I had to do was drill out the part of the gasket that went over the holes and it lined up after that.
    Al
     
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  13. JayFreddy

    JayFreddy Poster Extraordinaire

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    That had always been my previous experience too.

    Until this one.

    Yes, this George Allesandro speaker is a great product.

    Yup. Tried that first. Removed the gasket that went over the holes... Didn't work.

    I suppose I could have just mounted the speaker using only 3 of the original screws in their original locations, but that wouldn't provide the structural integrity of all 8 screws.

    I am very happy with how it turned out. It is very solid and no more speaker flub. Redrillling the screw holes in the baffle was the correct solution for this situation.

    I can't imagine anyone will need to replace this GA 12' for another 40 years. By that time, it will be out of my hands.

    Both literally and figuratively.
     
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  14. uriah1

    uriah1 Telefied Ad Free Member

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    Lot of work.
    I remember cutting off screws in DRRI to allow for 4hole Brit speaker.
     
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