Dsl40 Issue

Discussion in 'Marshall Amps' started by bambam789, Mar 18, 2019.

  1. ampmadscientist

    ampmadscientist Well-Known Member

    Joined:
    Jun 26, 2014
    Messages:
    13,319
    Likes Received:
    7,196
    Location:
    Start the reactor... Free Mars!
    Also try turning reverb to zero and retest.
     
    Mitchell Pearrow likes this.
  2. solarburnDSL50

    solarburnDSL50 Well-Known Member

    Joined:
    Aug 8, 2008
    Messages:
    15,503
    Likes Received:
    8,758
    Location:
    Wetville
    Try what ampmadschico recomends. He is a tech. Still weird... But a tech.:cheers:
     
    Mitchell Pearrow likes this.
  3. John BNY

    John BNY Well-Known Member

    Joined:
    Jul 13, 2013
    Messages:
    1,823
    Likes Received:
    2,530
    Location:
    New York
    Since the amp is not displaying any problems at the OP's home, I'm not sure what he would be looking for by running ant test. He needs to take the amp back to the town hall and test it there. If he only has a problem there, then it probably is the power source, or some bizarre acoustics there that's causing the feedback.
     
    Mitchell Pearrow likes this.
  4. bambam789

    bambam789 Member

    Joined:
    Mar 18, 2019
    Messages:
    20
    Likes Received:
    29
    Right I just tried what you suggested. Unplugged guitar so the amp was on it's own. Turned up full volume no squealing noise at all. Tapped the pre amp tube which made a very very slight ringing sound, tapped the other 3 in there & it was ever so slightly different to those but I mean if you hadn't said to listen out for it I wouldn't have noticed the difference.
     
    Mitchell Pearrow likes this.
  5. bambam789

    bambam789 Member

    Joined:
    Mar 18, 2019
    Messages:
    20
    Likes Received:
    29
    I personally don't think the ringing is anything to write home about as it was so faint it really wasn't even noticable. Maybe I was even half imagining it as you said to look out for it. Perhaps it is just the power down the hall all along?
     
    Mitchell Pearrow likes this.
  6. Micky

    Micky Well-Known Member VIP Member

    Joined:
    Apr 29, 2010
    Messages:
    20,223
    Likes Received:
    16,301
    Location:
    Vermont
    Microphonic tube. Put in your spare set.
     
    Mitchell Pearrow likes this.
  7. solarburnDSL50

    solarburnDSL50 Well-Known Member

    Joined:
    Aug 8, 2008
    Messages:
    15,503
    Likes Received:
    8,758
    Location:
    Wetville
    Every tube is micro phonic. If it's just a bit I'd think twice about changing.
     
  8. solarburnDSL50

    solarburnDSL50 Well-Known Member

    Joined:
    Aug 8, 2008
    Messages:
    15,503
    Likes Received:
    8,758
    Location:
    Wetville
    Course I've tube changed quite a bit. Some may think otherwise...
     
    Mitchell Pearrow likes this.
  9. mirrorman

    mirrorman Well-Known Member

    Joined:
    Mar 30, 2014
    Messages:
    727
    Likes Received:
    861
    Location:
    Canada
    Are you sure it's your amp that's squealing and not a PA speaker?
    Sounds to me like you may be getting feedback from a mic through the PA.
    When you were at the hall, did you try moving your amp to a different location?
     
    Mitchell Pearrow likes this.
  10. bambam789

    bambam789 Member

    Joined:
    Mar 18, 2019
    Messages:
    20
    Likes Received:
    29
    It definitely wasn't coming from the PA speaker, definitely coming from my guitar amp. That is another possibility though, it could of been mic feedback coming out of the pa speaker & my guitar amp picking up the signal. I do have my mic on in the shed when practicing on my own as I'm the singer too but don't have the mic level as high as in band practice. Maybe that was it. I'll go out to the shed to try now & have my amp on the same volume as band practice but turn up the volume on my vocal mic.
     
    Mitchell Pearrow likes this.
  11. Mitchell Pearrow

    Mitchell Pearrow Well-Known Member

    Joined:
    Jul 2, 2018
    Messages:
    7,611
    Likes Received:
    10,797
    Location:
    Moreno Valley CA
    Welcome to the forum new brother, you are in good hands here and you will shortly see the problem solved! And I also agree with both Solar, and Micky about a set of spare preamp tubes, and testing again one at a time, and at the rehearsal hall ! Cheers to getting your amp back to normal! Mitch
     
  12. bambam789

    bambam789 Member

    Joined:
    Mar 18, 2019
    Messages:
    20
    Likes Received:
    29
    Tried the vocal amp on in the shed & nothing noticeable happening. It seems to be linked to the hall I play at as everything I try in shed is fine. So that tells me it can't be the tubes as I would have the same problem I'm having in hall in my shed. So it narrows it down to the power at the hall not being too good or the feedback from my mic affecting my guitar amp more at the hall which is very possible due to the acoustics & natural reverb the building produces.
     
  13. bambam789

    bambam789 Member

    Joined:
    Mar 18, 2019
    Messages:
    20
    Likes Received:
    29
    Thanks, everyone on here has been so helpful. I didn't expect this level of help to be honest but I've learned to much just from what people on here have said today. Love Marshall amps & love this forum now. Just want peace of mind in my head as what it could be now!
     
  14. mirrorman

    mirrorman Well-Known Member

    Joined:
    Mar 30, 2014
    Messages:
    727
    Likes Received:
    861
    Location:
    Canada
    A couple of suggestions for you when you are at the hall:
    - Try your amp with the same settings in the same location with everything else turned off and unplugged. See if you still get that squeal. If you don't, you may be getting feedback from something else. Then try plugging and turning on each of the other amps, mixer, etc. one at a time to see if you can find the culprit that way.
    - Another thing to check is if your amp is using the same power source as any other equipment (using a common power strip, circuit, etc.) If it is you may be getting stray current feeding back to your amp. Try it in its own receptacle if you can.
    - Try plugging your amp into a different circuit.
    - If none of the above work or you get squealing with no other electronics on, you might want to consider trying a power conditioner.

    At any rate, best of luck in getting this sorted out...gremlins are a bitch!
    And, please keep us posted on how you make out...it might help someone else in the future!
     
  15. bambam789

    bambam789 Member

    Joined:
    Mar 18, 2019
    Messages:
    20
    Likes Received:
    29
    Yes thanks I will try your suggestion. I'm leaning towards thinking it's either mic feedback or something to do with the power source at the hall. I get the feeling if I unplug everything from the amp & turn up full volume in hall I won't get any squealing sound at all, it's only my gut feeling though.

    I suppose it's a good thing in a way that it's not the amp. I will look into testing everything next time I am down the hall. I will also take a longer extension lead so I can get my guitar amp further away from the PA speakers. I think I can clear it in my head from all the responses on here it's nothing to do with the amp now. I hope!......
     
    tce63, mirrorman and Mitchell Pearrow like this.
  16. mikebinthesky

    mikebinthesky Member

    Joined:
    Feb 23, 2018
    Messages:
    37
    Likes Received:
    33
    I would definitely swap spots at the hall with another bandmate and a different outlet. These kind of things can be mysterious.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice