JTM 45 & Bluesbreaker? Same amp?

Discussion in 'Amps and Cabs' started by illini, Oct 15, 2008.

  1. illini

    illini Member

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    Is the Bluesbreaker a JTM 45 in a combo?
     
  2. shngn7

    shngn7 Member

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    I am no expert on them whatsoever but I believe the Bluesbreaker features a tremolo circuit which decreases the gain capabilities and the JTM 45 doesn't. Someone will surely correct me if I am wrong.
     
  3. Rocket Brother

    Rocket Brother Member

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    You sir, are right.
    The only other difference is the Bluesbreaker is a open back 2x12", whereas the JTM 45 is a head most often paired with a closed back cab.
    RB
     
  4. illini

    illini Member

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    The tone of the few clips I have heard of the Bluesbreaker sound different than a JTM 45. The combo sounds more bluesy than the clips of the JTM 45. Can you get the ACDC tone out of the combo's?
     
  5. epluribus

    epluribus Member

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    They sound very different to me too--the Bluesbreaker seeming to break up earlier and edgier, with boxier mids and softer highs. Definitely a signature sound and feel, very distinct from the '45.

    Always suspected it has more to do with the actual parts Marshall sourced during production than changes to the schemo's. IIRC, they were using Dagnall/Drake transformers and Marconi KT66's during the bulk of Bluesbreaker production, but JTM45s have a somewhat tighter character that may be the result of a change in suppliers during the height of production. Always wondered about that--sounds like more goin' on in there than the cab and speaker choices would account for. Sounds like maybe a bit softer transformers and tubes that saturate a tad earlier and deeper than what they used in the heads.

    Fosse-natin'. Different critters for sure.

    --Ray
     
  6. illini

    illini Member

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    To bad really. I like both amps, and it would be great to "kill with one stone" as they say. Not sure what I will do now.
     
  7. epluribus

    epluribus Member

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    Not that you couldn't do approximately that...I suspect a Bluesbreaker with a speaker-out running into a JTM45-style cab would make an excellent rig. I'd certainly do a trial run if I had a Bluesbreaker to begin with--but I'd love to have a Bluesbreaker in any event!

    As for Angus Young sound, correct me if I'm wrong but I believe he uses Plexi's pretty much, though the '45 is still in the lineup. Wikipedia has a nice writeup on his rigs.

    Plexi's are basically later and more agressive versions of the JTM45 and Bluesbreaker circuits, with the most obvious difference being an eventual switch to EL34 power tubes, Mullards IIRC. (See Dr. Tube's website for the scoop--been a while since I last looked at the schematics.) Those would have a more agressive drive and an even edgier grain to the breakup than the Bluesbreaker-era KT66's, IMHO. Just a dab of dirt or boost, something rather touch-y and tube-y, in front of a 'Breaker would probably get you there very nicely. So would a gentle tweak on the bias or maybe the bypass caps--much preferable to pedals in my book.

    The other big evolution was the late change from the GZ34 rectifier tube to a solid state system, which would probably stiffen up the amp quite a bit. Hard to say which generation of Plexi Angus uses, but it sounds like the earlier ones judging by the web histories.

    Anyhoo, don't know if the Bluesbreaker is what you want for Angus Young sound, tho I've heard a ton of guys create an excellent sense of his tone with all sorts of different rigs. Seems to me Angus is much more about getting the mojo just right than any special rig. But geez-o-peetz, if you have a Bluesbreaker layin' around, I'd hang on to it...or you could mail it to me...

    :)

    --Ray
     
  8. illini

    illini Member

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    Don't have one laying around.:) Wish I did.
    I played a reissue bluesbreaker a few months back, and was actually rather taken by it. I have a 71 Fender Vibrolux that I have been toying with the idea of selling to pick up the bluesbreaker. Have you played the reissues? Do you like them as much as the originals?
     
  9. 908SSP

    908SSP Supporting Member

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    My BB and JTM45s
    [​IMG]
    [​IMG]
    [​IMG]
     
    Bftguitar likes this.
  10. shngn7

    shngn7 Member

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    Bluesbreakers look so cool! I would really like to own one of those some day being a combo man myself.
     
  11. Frankee

    Frankee Wartime Consigliere

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    A Bluesbreaker on top of a Bluesbreaker cab is also an impressive rig........
     
  12. RCCola

    RCCola (|@ / \ @ |.) Gold Supporting Member

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    What is that? Do you have 1 of the 3 known JTM45 offsets? That looks like a 2x12? The RI I had had different grill cloth:

    [​IMG]
     
  13. RCCola

    RCCola (|@ / \ @ |.) Gold Supporting Member

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    Ah, nm. Looks like a custom build. Sweet.
     
  14. 908SSP

    908SSP Supporting Member

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    Yes custom. More info later.:AOK
     
  15. illini

    illini Member

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    I have a shot at a 91 Bluesbreaker reissue for $950. Don't know the condition yet, but may be worth looking at.
     
  16. epluribus

    epluribus Member

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    I'd love to hear opinions here from owners of both, they're such landmark amps. Personally, I've never played an original, though I've heard them played live in small settings many times. Really liked the reissue, thought it played terrifically as this sort of circuit goes, and really covered the old tone well. Though I've not really looked under the hood, I wouldn't be surprised if what subtle changes exist are down to modern reliability as well as affordability.

    As for owning a Bluesbreaker, my current rigs get me there quite well, but my opinions are changing...lately I've been exploring the turf a lot more and basically gotten pretty taken with 'em. Been tinkering with a 'Breaker-style circuit on my workbench and I may have to break down and actually build one--I like it that much. Nothing else sounds like 'em, purely awesome amps for blues and blues-based rock.

    --Ray
     
  17. 908SSP

    908SSP Supporting Member

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    I'd pass on the 91 as the cab is only 9.5" deep instead of the 10.5" like later reissues and the originals. You can't fit KT66s in the 9.5" cab and that is an important upgrade to getting closer to the original sound.

    Here is what you'd like it to look like inside.

    [​IMG]
     
  18. illini

    illini Member

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    Well that is disappointing. I was planning on looking at this amp tomorrow, and was thinking seriously about pulling the trigger. Did the originals come with KT-66's?

    So....you think I should pass, huh?
     
  19. Metalheart

    Metalheart Member

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    Looks killer!:drool
     
  20. Flux

    Flux Member

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