Tube rustling sound ,in se amp ????

Discussion in 'Tube Audio' started by klipschoid, Apr 19, 2017.

  1. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    1. question .My amp uses 1 6dj8 pre tube but amp has been making a rustling noise so i pulled the 6dj8 and turned it on and no noise,so i wonder if its that tube or an output tube,pins were clean and i didnt leave it on long ,could the pre have a bad internal joint? I ordered a nos sylvania to replace it.previously when it was doing it i had no input connected and moved the tubes around,to see if it was a pin problem,wiggled them,but no change ,rustling is out of my left channel,i crossed my el84 tubes left to right no change,still in left channel,btw its one el84 per ch not pp .So this leads me back to the pretube,i cant narrow further because it drives both channels ,thanks for any help or similar experiences

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      klipschoid
     
  2. maxhifi

    maxhifi Super Member

    Messages:
    1,259
    Location:
    Canada
    I think you're on the right path to try substituting a new tube as the first step. There's a possibility its a noisy resistor or something else, but trying a new tube is the smartest thing to do at this point.
     
  3. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    Thankz appreciate the reply
     
  4. gadget73

    gadget73 junk junkie Subscriber

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    Southern NJ
    I've had noisy tubes before, usually it sounds like a wind blowing sort of sound. Swapping for another one is the easiest way to check for it.
     
  5. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    Ok ,yes i have a nos sylvania 6dj8 pair coming,ill try.it has an old rca in it now.rca is good but it could be jus wearing out,internal dry joint on the left side of it ,etc.I cant offord telefunkens right now.If this fixes it i may save for some more tubes ,this amp plays plenty loud on my corns ,i may bi amp them later,if theres an easy way((6 ohm resistor maybe where the woofer was type of thing)),but i know this is not inductive like the woofer ,.and keep my triode on the mid-highs ,but prob not worth the trouble,bass is there if its meant to be,in the recording
     
  6. gadget73

    gadget73 junk junkie Subscriber

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    If you're going to bi-amp, it makes more sense to split the frequencies before the power amplifier. It makes it so the amp only has to reproduce what you need at the speaker rather than the whole frequency range and throwing away part of it. Basically its a line-level crossover.
     
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  7. CZ4A

    CZ4A Active Member

    Messages:
    168
    Location:
    Methuen, MA
    I've noticed a rustling sound in a Tung-Sol black glass 12AU7 before, and it turned out to be an intermittent internal short. Putting silicone damper rings on the tube and cleaning the pins with Deoxit helped reduce the noise. If you can put that 6DJ8 on a tester you can check to see if it is shorting out.
     
  8. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    Ok,ya no tester and ill see if swappin that 6dj8 will help ,almost like its emitting when it shouldnt ,thats with no input,if this doesnt help ill see if a resistor is going ,but its got decent allen bradley resistors and solen caps ive seen so far.But doesnt mean there cant be a cold solder somewhere,and gyrating the tubes in their sockets doesnt make it do it,so,ill post when i swap that 6dj8 ,thanks yall
     
  9. gadget73

    gadget73 junk junkie Subscriber

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    31,440
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    Southern NJ
    Some quick Google-fu tells me A-B stopped making resistors in the 1990s. Thats a fair long while ago.
     
  10. vonclod

    vonclod AK Subscriber Subscriber

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    Vancouverish
    I'm watching this thread..I have a Sonic Frontiers integrated that does this..even with the mute switch on, have changed all the bottles too.
     
  11. gadget73

    gadget73 junk junkie Subscriber

    Messages:
    31,440
    Location:
    Southern NJ
    if changing the tubes does nothing, plate resistors would be my next guess. Carbon comp resistors in particular tend to get funky like this.
     
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  12. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    Ok on the AB resistors,hope its just a tube,ill report when i get it in the mail and fired up again
     
  13. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    Would yall think if its a resistor ,itd be a resistor on the preamp tube plate? It only does it in left channel,and of course not at all if the preamp tube isnt in,btw still learning tubes
     
  14. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    And with no preamp tube in,those output tubes are still getting their b+ and no noise to be heard without that pretube in ,im jus narrowing it down my way ,lol ,but i proudly take advice as well
     
  15. Northwinds

    Northwinds Huh? Turn what down? Subscriber

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    I was just going to suggest the damping ring then saw your post :rockon:
     
  16. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    Didnt do anything but push the amp hard yesterday and today no rustling,hmmm ,i think its getting rf interference from something,or the pre tube had a bit of air in it or moisture and now it has burnt up or dried up ,i dont know
     
  17. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    So ya jus push your amp hard once in a while,try that ,only thing i can figure is the input grid on my pre tube is iffy,and pushin more voltage into it did something to it,because even pushing a tube amp harder doesnt heat it more like class ab does ,so any clue why pushin it would help?
     
  18. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    My nos 6dj8 is coming today ,ill see if that quiets my amp down and ill post back
     
  19. Dadbar

    Dadbar Super Member

    Messages:
    1,779
    Location:
    Waltham & Gloucester MA
    I've had that rustling noise happen with dirty tube pins. Clean and retension the sockets...that might fix it.
     
  20. klipschoid

    klipschoid Active Member

    Messages:
    120
    Location:
    groves,texas
    Ok thankyou
     

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