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Mid-70s Twin Reverb vs Early-70s - Is the MV the only difference?

Discussion in 'Amp Central Station' started by itsGiusto, Dec 24, 2020.

  1. Viejo

    Viejo Tele-Afflicted Silver Supporter

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    The lead dress got progressively sloppier as the 70s progressed eventually requiring parasitic oscillation suppression mods. The cabinets changed from pine to high density fiberboard adding weight to an already heavy amp and changing the sound. The biasing system changed from bias adjust to bias balance adjust.
     
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  2. itsGiusto

    itsGiusto Tele-Holic

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    What year did they change from pine to HDF?
     
  3. 39martind18

    39martind18 Friend of Leo's

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    When the silver face Twins first came out in late 1967-early 1968, they had the BF circuit. In May, 1968 CBS went to the 568 circuit, which was fairly easy to "Blackface." I had a 1968 that had the later circuit, and had it blackfaced. Interestingly enough, I really couldn't tell much difference between the two. YMMV
     
  4. itsGiusto

    itsGiusto Tele-Holic

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    Does anyone have any advice for how I can tell if the speakers on a '67 are original?
     
  5. BobbyZ

    BobbyZ Doctor of Teleocity

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    Speaker date codes give a pretty good idea, obviously the speaker should be a little older than the amp. But if you want to date JBLs it's another story, as far as I know there isn't a date code on them and whatever serial number system they might have had was lost in a fire.
    So you guess, a 60s amp would have gray frames, the orange frames came out in the early 70s I believe. Some JBL equipped amps might have a badge on the front, or you might have something noted on the tube chart. Also since JBLs frames are so thick, if the amp has factory hardware the right length it probably had JBLs to start with.

    A link. https://tedweber.com/speaker-codes-application/
     
  6. Wally

    Wally Telefied Ad Free Member

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    BobbyZ, I think you misunderstood my post. Perhaps my use of ‘never’ and ‘unable’ together was confusing. Perhaps I should have written that I have ALWAYS been ABLE to make a SFTR sound good...no matter the year of production...UL included.
     
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  7. Wally

    Wally Telefied Ad Free Member

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    A factory JBL-equipped TR from that period will usually have the JBL badge in the lower right hand corner of the grille.

    https://reverb.com/item/14484485-fender-jbl-twin-1968
     
  8. premiumplus

    premiumplus TDPRI Member

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    I had a mid to late 70's Super Reverb with the boost circuit, and it sounded great. I'm pretty sure it still had a pine cab though, and the good CTS Alnico speakers.
    I'd watch out for the ultralinear Twins though. They used different transformers and you can't go back on those without expensive transformer changes.
     
  9. Kansas

    Kansas TDPRI Member

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    I’m 72 and have seen lots of guitars and amps go from “Who cares?” status to “Oh wow!” status. Buy what you want and can afford and figure in the long run you’ll be fine financially. Once in a while you might get nicked but if you play something because you like it, so what? We aren’t talking stocks and bonds. It’s art, fun, and a great hobby.
     
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  10. GoodAugust

    GoodAugust TDPRI Member

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    As others have said, if you don't like the idea of a master volume, just turn the master all the way up and control your volume at the input. The only thing with master volumes I don't like are the Push/Pull. Just leave it alone, it sounds like ****.
     
  11. ampsplus

    ampsplus TDPRI Member

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    2 main differences in 1972 with Fender amps. These all started with the Twin Reverb:

    1) added master volume, at first just a master, but within a couple of years this also became a pull boost. Don't forget, there is extra signal wiring added in these amps, and the lead dress is messy, requiring the addition of the bleeder capacitors on the o/p tube sockets.

    2) 1972 was the first year of the new cabinets, with the integral baffle. The cabs were still made up of pieces of pine, but now used lap joints instead of the finger joints, as used earlier, and there was a groove routed into the side panels that the baffle was slid into and glued. These cabinets are not as strong and are notorious for starting to come apart as they are bumped around. Not a great design at all, and done to expedite cabinet assembly.

    I would look for 1971 and earlier.
     
  12. Pluck Rogers

    Pluck Rogers TDPRI Member

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    I bought a 1977 Twin Reverb for use in gigs in pubs and clubs playing in a covers band with drums. bass, keyboard and another guitar. It was WAY too powerful. I never had it turned up much above 3 and that was unmiked. Changed it for a MusicMan 65 1x12. Which was MUCH better.
     
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  13. shawnoh4

    shawnoh4 TDPRI Member

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    I've had an early 70's twin with a master volume, and it's great. But it could have been better, with a Master-Master volume control. It lets you dial in natural amp distortion way better than the standard Master volume. So either way you should get the mod. If I were in your shoes I would get the early 70's twin, 71-74, and have a tech put a master master volume on it. The push pull switch just adds a moderate blues grit. If you use pedals, you can get more distortion that way. but a master-master volume does a lot more of what you are ultimately looking for. It won't be a mesa-boogie, but it will be a lot hotter sounding amp with the mod.
     
  14. Clifton C

    Clifton C Tele-Afflicted

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    I’m lucky enough to have a Music Man 212HD 130. What a great amp! Very similar to a 70s Twin Reverb.
     
  15. Erwin

    Erwin Tele-Meister

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    If you have an hour of time, this video can explain you in more detail than you would care to know about the differences and how much these have an impact on the sound of the amp. This guy knows his amps and he knows a lot about electronics in general:

    The difference in the Phase Inverter is one that he explains in detail why it is that way and why it does not matter that much.
     
  16. moosie

    moosie Doctor of Teleocity Silver Supporter

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    A quick google shows that there's a 69 Twin for $800 right now on Reverb, shipping from the midwest US.

    I can't speak for that one, but I sure love my 69.
     
  17. Mexitele Blues

    Mexitele Blues Tele-Afflicted

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    My apologies Wally, I had quoted a humorous autocorrect that had me imagining mopeds waiting at a stoplight instead of electrons rushing the PI grid.
     
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  18. davedederer

    davedederer TDPRI Member

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    An amp with anything close to a 4x6L6 Twin Reverb layout is going to sound loud and clean and good (unless it's broken) and honestly any variations on that on TRs seem pretty random to me in terms of TR model year. For the record, I made a 6x platinum album with a beat-to-hell original blackface TR (with two mismatched speakers, one of which was held on by only two bolts) and toured the world for years playing various TRs, Dual Showmans, and other 4x6L6 amps.

    I would also note that the red-knob "evil Twin" despised by so many is beloved by two of the greatest guitarists of all time (Robben Ford and Steve Cropper) and also was used by one of the absolute most amazing guitarists I've ever heard and seen, Crispian Mills of Kula Shaker. FWIW, years ago (mid-90s) he played through a cheap Boss multi-effects pedalboard into an evil Twin and sounded better than the last time I saw and played with him, when he had a massive custom pedalboard and a couple of fancier amps.
     
  19. itsGiusto

    itsGiusto Tele-Holic

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    +130 shipping. Puts it into a different price bracket if you ask me! If I paid that much, I'd probably want at least one speaker to be original, and that one does not have either one original.
     
    Last edited: Dec 29, 2020
  20. itsGiusto

    itsGiusto Tele-Holic

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    What is a master-master volume control? Are you referring to a post-PI MV?
     
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