Crack working one minute - dead the next [Resolved]

mickp elijah audio · 1380

0 Members and 1 Guest are viewing this topic.

Offline mickp elijah audio

  • Newbie
  • *
    • Posts: 5
on: December 15, 2016, 02:31:09 AM
Hi all , first post and as a tube newbie, I will no doubt be returning for more help
I bought a standard Crack secondhand - and had to do a bit of resoldering to get the right channel working
I am blown away by the sound through my also recently purchased HD 650's
Tonight's issue (midnight , Adelaide , Sth. Aust)
Used the Crack last night, and switched it off when finished - went and turned it on tonight - DEAD - The fuse is OK
Any ideas why it would behave like this ??
Thanks for any help
Michael Parin
CEO Elijah Audio
« Last Edit: December 16, 2016, 09:39:07 AM by Caucasian Blackplate »

Michael Parin
CEO Elijah Audio


Offline Tom-s

  • Sr. Member
  • ****
    • Posts: 496
Reply #1 on: December 15, 2016, 04:32:44 AM
Perform resistance and voltage checks.



Offline mickp elijah audio

  • Newbie
  • *
    • Posts: 5
Reply #2 on: December 15, 2016, 04:42:50 AM
Thanks, but I thought those checks were only performed to get a new Crack working
Mine has been working OK for 2 weeks and  now won't fire up
Does it mean something , e.g. the transformer, has died ??

Michael Parin
CEO Elijah Audio


Offline fullheadofnothing

  • Global Moderator
  • Hero Member
  • *****
    • Posts: 1487
  • A noble spirit embiggens the smallest man
Reply #3 on: December 15, 2016, 06:34:53 AM
If something was wrong with the transformer, it never would have worked in the first place. The odds of getting a bad transformer are essentialy zero. When we have had problems with transformers, the problem has been traced to improper installation damaging the transformer, and not a defect in the transformer.

Your problem is almost certainly a poor solder joint that has expanded and contracted with heat from being turned on and off. Resistance and voltage checks will help locate the problem.

Joshua Harris

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


Offline mickp elijah audio

  • Newbie
  • *
    • Posts: 5
Reply #4 on: December 15, 2016, 08:08:07 AM
Thanks - as I have already had to fix a few dud  solder joints - this is good news
I will report back ASAP
Thanks again

Michael Parin
CEO Elijah Audio


Offline Doc B.

  • Administrator
  • Hero Member
  • *****
    • Posts: 9641
    • Bottlehead
Reply #5 on: December 15, 2016, 08:13:29 AM
Check that the power switch contacts are actually closing with your DMM. Sometimes the switch is damaged when installed and makes intermittent contact.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline mickp elijah audio

  • Newbie
  • *
    • Posts: 5
Reply #6 on: December 15, 2016, 12:26:03 PM
Thanks to all - sweet music again
I reflowed a couple of joints on IEC socket  and also clipped a couple of bare wires that were very close to neighbouring wires
Not sure which one did the trick, but I am a happy camper once again  :)

Did you hear about the farmer that won the Nobel prize?
He was out standing in his field.............
Thanks again

Michael Parin
CEO Elijah Audio