Ampeg Flat Back date help

Discussion in 'Amps and Cabs [BG]' started by Steve Moerke, Dec 24, 2020.

  1. Hello, I am considering purchasing an Ampeg Flat Back 8x10 speaker for my 71 SVT. How can I date the cabinet? I can’t find this information on the internet. I attached a picture of the serial number tag on the speaker. Can someone guide me to how you can tell by the serial numbers what the manufacture year is and where?


    Attached Files:

    Last edited: Dec 24, 2020
  2. davelowell2

    davelowell2 I’m not superstitious. Maybe a little stitious. Supporting Member

    Apr 20, 2006
    I think the only method is to use speaker codes for dating. Do you have a picture of that?
    bobyoung53 likes this.
  3. coreyfyfe


    Nov 19, 2007
    boston, ma
    Yeah speaker date code would really be the only way. The flatbacks were only made for a few years so not that large of a window either way.
  4. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    Ya, they're right. Serial number info has been lost to the ages.
  5. No unfortunately I do not have any pictures of the back of the speakers. If I get that info I will post it.
  6. Doesn’t the fact that it has a Linden Mfg. location help date it?
    bobyoung53 likes this.
  7. coreyfyfe


    Nov 19, 2007
    boston, ma
    Not really any more than the flatback design does. Magnavox moved production to Indiana around 1974, the flatback design transitioned to the tilt back design around the same time.
  8. beans-on-toast


    Aug 7, 2008
    Many flatbacks had alnico speakers, some had ceramics. You’ll never know what you have till it’s opened up. BTW, unless the speakers fasteners have been changed, you might need to find a 5/32” clutch head screwdriver.

    davelowell2 likes this.
  9. Oren Hudson

    Oren Hudson

    Dec 25, 2007
    Gastonia, NC
    Those clutch heads are a pain, but easier with the clutch head screwdriver. :)
    beans-on-toast likes this.
  10. I didn't even know those existed. Looks like a good design though.
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  11. beans-on-toast


    Aug 7, 2008
    They were a very good sounding cabinet. One issue is that they're limited to 240W, that's why Ampeg used to recommend two cabinets with the SVT in the early literature. The Heritage 810 is their only cabinet that sounds as good as the old flatback, an big advantage is that it has a higher wattage capacity.
  12. Apologies, I know of the flat back cabs, they've got oldschool Ford Flathead V8 cool going on.

    I meant the clutch head screws were new to me
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  13. beans-on-toast


    Aug 7, 2008
    Ampeg used them, Ford did on some old truck headlight housings, some farm tractors used them, as did Airstream on camping trailers. They were short lived and not that popular.

    Given the shape, batman must have used them on the batmobile.
    coreyfyfe and pie_man_25 like this.
  14. There are a surprising number of screw types that aren't all that popular. I kinda hate the standard screw, and Phillips (it's not bad, just hard to apply any real torque onto without it popping out by design), but I wish more manufacturers used torx and Robertson.
    Last edited: Dec 26, 2020
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