Random single Pop noises from new SEX

yay · 4085

0 Members and 1 Guest are viewing this topic.

Offline yay

  • Full Member
  • ***
    • Posts: 67
on: May 09, 2017, 04:41:22 AM
So i've been using my SEX now for a few days, and a few times a day a single pop comes from the speakers (and headphones). Most of the time on the left side, but i have heard it from the right side before. There doesn't seem to be a pattern when it happens, it just happens randomly. Like once an hour or so, not sure.

The noise FAQ says something about failing capacitor?
My measurements are all on point, and i thoroughly shook the amp to make sure no debris is still stuck inside and no bad solder joints seem to be present.

Should i just resolder some specific joints first?



Offline Mordicai

  • Full Member
  • ***
    • Posts: 174
Reply #1 on: May 09, 2017, 05:08:40 PM
Are you using a C4S? I had the same problem and turned out to be a bad solder connection on the center lug of the transistors on the C4S. Mess around with a chop stick while powered on and you will probably find it.



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #2 on: May 09, 2017, 09:27:07 PM
no, not using the c4s - i got the 3.0.
should i have speakers plugged in while chopstickin' around or just voltage measure/resistence measure?



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #3 on: May 10, 2017, 03:42:20 AM
i chopped around while running, tapping everything a few times, waggling around and could not reproduce the pop or other sort of noise, everything seems well in that regard.
« Last Edit: May 10, 2017, 03:49:58 AM by yay »



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #4 on: May 12, 2017, 12:25:24 AM
anyone got other ideas what i should check?
should i post pictures of the interior? i guess i will do that in a bit, can't hurt i guess



Offline mcandmar

  • Hero Member
  • *****
    • Posts: 1599
  • Not all engineers are civil
Reply #5 on: May 12, 2017, 12:28:44 AM
Could be a bad connection, which it looks like you have covered above.

Could be a bad tube, i have come across a few 6DN7s that will work fine, but every now and again give a very loud pop, enough to make your ears ring when using headphones.

Could also be mains noise, something electrical switching on/off in the house.  Light switch, washing machine, AC units etc.  ...probably the most likely scenario.

M.McCandless


Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #6 on: May 12, 2017, 01:46:10 AM
Could also be mains noise, something electrical switching on/off in the house.  Light switch, washing machine, AC units etc.  ...probably the most likely scenario.

wouldn't i have the same with my crack then? only have it with the SEX, and 80% of the time only in left channel



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #7 on: May 13, 2017, 09:15:47 AM
i ran the amp without input, but speakers connected and the pops still came. does that narrow it down a bit?



Offline fullheadofnothing

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 1487
  • A noble spirit embiggens the smallest man
Reply #8 on: May 13, 2017, 09:55:58 AM
Have you reheated every solder joint yet?

Joshua Harris

I Write the Manuals That Make The Whole World Sing
Kit Packer Emeritus


Offline Paul Birkeland

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 19826
Reply #9 on: May 16, 2017, 07:57:25 AM
You almost certainly have loose connection.  You almost certainly do not have a failed capacitor (that requires either 20 years of use or putting the cap in backwards during your build).

As others have mentioned, you can power the SEX up and hook it up to an inexpensive speaker (I suggest getting something from the thrift store or pulling one out of an old TV).  You can poke around in the circuit with a wood chopstick and eventually you may find a joint that, when disturbed, will cause popping out of your test speaker.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #10 on: May 23, 2017, 09:05:08 PM
i have reheated everything, but my solder iron broke and already wasn't working very well during the reheat.
i was gone for a few days, and have a new iron now. in a few days i will update here once i resoldered everything again. after the resolder i introduced a buzz, probably because the iron didn't seem to be heating very well and some connection i resoldered actually got worse  ::)



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #11 on: May 27, 2017, 09:24:43 AM
resoldered every joint thoroughly with a much better working solder iron, problem still persists. not sure what to do



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #12 on: May 28, 2017, 04:35:23 AM
i have some extra information, which might be relevant or normal:
when i have my crack plugged in, and turned on and then turn on the SEX i can hear a THOCK through my headphones (plugged into crack) - without inputs connected to the SEX, only sharing same outlet.



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #13 on: May 28, 2017, 07:34:54 AM
I took a bunch of pictures, not sure if it's too many to post



Offline yay

  • Full Member
  • ***
    • Posts: 67
Reply #14 on: May 31, 2017, 10:39:11 PM
again i tried to chopstick around very very thoroughly, and not softly.
i could not produce the pop or any noise of any kind. the solder joints seem very solid, i ripped at the cables, tapped all joints and other parts, waggled everything around while using cheap headphones (pop is with speakers and phones) and could not get the sound to reproduce.
i'm seriously at a loss right now, i would try any farfetched idea you guys have.