Jubilee 2558 issue?

Discussion in 'The Workbench' started by marco_giampa23, Aug 20, 2020.

  1. marco_giampa23

    marco_giampa23 Well-Known Member

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    So I went to trade my 2558 combo today and the buyer played with the amp for a while and just hated it. Now this is my first real valve marshall (had a 5w sl5) and i havnt heard many jubilees or marshalls in person so it sounds great to me but he was throwing words around like "boxy" and "no balls" and said that there is definitely something wrong with it andit just sounds bad.

    What could this "bad sound" be? Its got the original filter caps and 2 of the pre amp tubes are random, maybe its biased really cold? I have no clue, here is afew gut pics i can add more possibly
    IMG_20200326_162317 (3).jpg IMG_20200326_162342 (3).jpg
     
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  2. JM5010

    JM5010 Active Member

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    Is the amp biased properly?

    What tubes are in the preamp? If you do not know the brand, swap to Tung-Sol's.
     
  3. Shawn Kawvey

    Shawn Kawvey Active Member

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    ..
     
    Last edited: Sep 3, 2020
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  4. marco_giampa23

    marco_giampa23 Well-Known Member

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    no clue on bias, power tubes are svetlana's.
    for pre amp tubes V1 is an EHX and the other 2 are unmarked exceot for afew wierd letters, might swap them out, ive added a photo of one

    IMG_20200329_140334.jpg
     
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  5. JM5010

    JM5010 Active Member

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    Bias it properly. Play a few chords. Swap the preamp tubes around (put the EHX in V3 etc...)

    If it still doesn't sound good, get new preamp tubes and test.

    If it still doesn't sound good after any of the above, it may be time to replace the filter caps with some F&T 50+50uf cans :)
     
  6. marco_giampa23

    marco_giampa23 Well-Known Member

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    dont 100% know how to check bias, i swapped the tubes around, not sure which socket is V1 but just the EHX tube went to the opposite side and i swapped the other two around and i think it sounds different in the new position, ill add the vids in a minute when they upload
     
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  7. JM5010

    JM5010 Active Member

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    Sounds like you may have found the issue.
    If you don’t know how to bias your amp take it to a tech
     
  8. Sg-ocaster

    Sg-ocaster Well-Known Member

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    Honestly there may be nothing wrong with it......was the buyer looking for the jubilee sound?? Or was he looking at it based on their reputation and looking for a different sound?
    I ask this because I bought one years ago based on the hype not knowing their sound ......i too used terms like boxy no balls and clunky.....i sent mine in for repair once only to have it sent back saying nothing was wrong......turns out after a year of struggling with it I just hate the jubilees sound. Tried others and don't like them either.
     
  9. mickeydg5

    mickeydg5 Well-Known Member

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    Bias adjustment about mid up.

    What is the serial #?

    Has it been modified?

    Is the amplifier output impedance always matching the cabinet impedance?
     
  10. marco_giampa23

    marco_giampa23 Well-Known Member

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    he said he had a 5150 that sounded "way better", idk maybe he was just running a wierd eq and thats why it didnt sound its best, it hink it sounds fine, i can understand not liking it but he said that "there is definitely something wrong with it"
     
  11. marco_giampa23

    marco_giampa23 Well-Known Member

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    Im pretty sure the bias trimpot is facing straight down if thats what you mean

    S/N is 03721

    as far as I know its not modded, thats why i added a gut shot to see if anything stands out

    and yeah im on 8ohm mode, 2 16ohm speakers in parallel, speakers read 6.8ohms togethor
     
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  12. DonP

    DonP Active Member

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    This is how I described my 2525H when I got it. One of the power tubes was dead. Put in a new pair and it now sounds awesome.

    Yes, an amp can still run on just one power tube.
     
  13. Sg-ocaster

    Sg-ocaster Well-Known Member

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    Could it be he was hopeing you'd say " oh man really well I guess I could drop the price"(by allot)and he could "score"??
    Had that happen....my father had an early 1970s straight 4x12 marshall with 4x g12h in it bought it new. Buyer screw gunned the back off and said " oh they are all recones I'll give ya $xxx for it".....umm nope.
    Btw the 12ax7s you showed in the picture with the weird letters are old Ei flat plates....decent tubes better than current production stuff.
     
    Last edited: Aug 21, 2020
  14. marco_giampa23

    marco_giampa23 Well-Known Member

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    Maybe, could be he pulled that instead of of just straight up saying that he doesnt like it, was actually trade that probably looking at it now wasnt very good my way ('04 LP standard with a good headstock repair and a full refin)

    Thanks for identifying the tubes too, been trying to find out what they are, how can you tell, just curious
     
  15. marco_giampa23

    marco_giampa23 Well-Known Member

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    Here is a video I made just for myself to compare the preamp tube positions, tbh this amp sounds great to me but if anyone else thinks it sounds like there is something wrong with it...

    Btw this is recorded on my phone sitting on the ground right in front of the amp

     
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  16. mickeydg5

    mickeydg5 Well-Known Member

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    Ok.
    From that audio clip give us the signal chain including all effects and settings, guitar settings, amplifier settings, cabinet types/configurations and speakers loaded in said cabinets.

    Further answer(s) to follow.
     
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  17. marco_giampa23

    marco_giampa23 Well-Known Member

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    My 2002 LP studio on the bridge pickup (498t), 500k pots both on 10, only pedal is a bypassed tu3

    amp settings are:
    input gain 6 - lead master 10 - master 2 - treble 2 - bass middle andpresence are around 7-8.

    50w mode, 2 original marshall g12 vintage "by celestion" speakers, 16ohm each, wired in parallel to make 6.8ohms

    thats about it, cant remember the exact eq settings at the time of recording but it was definitely treble around the 9 oclock are and middle bass and presence around 2-3 oclock
     
  18. Sg-ocaster

    Sg-ocaster Well-Known Member

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    The long smooth plates inside the tube and the 2a1 code on the glass that is Ei........only telefunken and Ei had those style smooth(flat) plates and Tele would have a diamond formed into the glass in between the pins on the base.
     
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  19. marco_giampa23

    marco_giampa23 Well-Known Member

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    t
    hanks nice to know, was going to swap them but they seem pretty good
     
  20. JacksonCharvelAddict

    JacksonCharvelAddict Well-Known Member

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    Maybe he was just expecting something higher gain. The Jubilee is a smooth amp and some people like the aggressive highs like a 2203 has. I have to laugh at him calling it "boxy" as that is just how combos sound unless you use an extra cab.
     

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