Right channel intermittently working

Petricore · 2018

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Offline Paul Birkeland

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Reply #15 on: August 24, 2020, 05:01:23 AM
And we will assume that you're not using a 1/4" to 1/8" adapter in the Crack but not your other amps.  (These are a common point of failure)

Paul "PB" Birkeland

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Offline Petricore

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Reply #16 on: August 27, 2020, 06:09:48 AM
I am using an adapter, always have with my DT880s (like I never unscrew it, its lived on them).

I bought a replacement and somehow the bias seems worse now, like the left can is louder and the right can is still softer.

I'll try to get ahold of another good pair of wired cans to test, I'm starting to suspect I need to recable these cans. I can wiggle it with the new screw on adapter and it crackles and sound changes.

I can also plug this exact setup into my DAC, which also has a built in amp and the cans sound level. Which is why I haven't been suspecting cans yet.



Deke609

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Reply #17 on: August 27, 2020, 06:13:28 AM
Post some pics of the headphone jack wiring from lots of different angles.

cheers, Derek



Offline Petricore

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Reply #18 on: August 27, 2020, 06:17:21 AM
Also, oddly, the time to evening out seems shorter, they are already closer than when I tested a few minutes ago.
Also again plugging into my solid state amp, I can't reproduce the issue.
I'm starting to wonder about the potentiometer I replaced a year or two ago (tho it functioned fine until recently if that's the case).



Offline Petricore

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Reply #19 on: August 27, 2020, 06:18:17 AM
Post some pics of the headphone jack wiring from lots of different angles.

cheers, Derek

Right, I keep forgetting sorry. I'm down one hand currently so things are taking a lot more time.
I'll try to get some photo assistance this afternoon :)



Offline Deluk

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Reply #20 on: August 27, 2020, 10:04:13 AM
After 9 years of use it's not unreasonable for the contacts in the jack to have got tired/broken/moved out of kilter. I would have just changed it out for a replacement BH one in the first instance. It's a good solid regular jack not a precision built for life item.



Offline Petricore

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Reply #21 on: September 09, 2020, 03:37:26 AM
Which one would you replace it with?
It also kind of would make sense that warming it up physically could help the contacts if they are just slightly out of whack.



Offline Paul Birkeland

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Reply #22 on: September 09, 2020, 04:38:22 AM
Tell us about the replacement pot.  What precipitated replacing the pot, and what pot did you use as a replacement. 

I wouldn't just toss the jack, I have seen those jacks at 20+ years of age still working nicely.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Petricore

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Reply #23 on: September 24, 2020, 05:59:31 AM
I replaced with a Audio Note 100K Ohm Stereo Balance Potentiometer with some advice I got here. I also added 33K and 75K resistors from another post here.

I replaced the pot because at low volumes one side of my headphones got really quiet, which I read was an issue with the stock pot.
I added the resistors to give me some more headroom on the volume knob.



Offline Paul Birkeland

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Reply #24 on: September 24, 2020, 06:04:30 AM
You can't just put a balance pot in place of the volume pot.  You can add the 33K and 75K resistors to the stock pot to even it out.  The balance pot needs to be removed, it will not function

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Petricore

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Reply #25 on: October 05, 2020, 03:38:13 AM
Right I apologize, I incorrectly bought a balance pot and then exchanged it for the same product in a volume pot. I remember when I installed the balanced pot it broke everything. Sorry for the out of order info there. I can try to find the stock pot if me replacing it is what is suspect here.



Offline Paul Birkeland

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Reply #26 on: October 05, 2020, 06:04:51 AM
At one point in this thread, you were certain that you had a bad headphone jack, and I provided you with a part number for its replacement.  Did you end up replacing it?

I still believe you have a loose connection in your amp.  The other possibility would be a failing tube (certainly a possibility after 10 years), but this would be clearly reflected in the voltage checks I had you do, and your tubes still seem to be working great.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Petricore

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Reply #27 on: October 09, 2020, 04:43:59 AM
I haven't replaced the headphone jack yet, you seemed pretty sure it wasn't. Definitely not trying to pick a fight, I appreciate your help. I'm also trying to be careful with my amp and not just replace things on a whim.

I will order a new jack and see if that helps!

As far as the tubes go, I have 3 aftermarket tubes and the stock tube and all 4 have the same issue.

I am happy to provide more info and be helpful, I've been too busy to keep up with it lately so I've just had the amp on all day/night and the issue doesn't seem to be happening. I'll report back after I get the new jack.



Offline Paul Birkeland

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Reply #28 on: October 09, 2020, 07:17:04 AM
Well, I can tell you that I repaired a Crack yesterday that came with a long note from the customer about how he had a dropping channel and resoldered his connections half a dozen times but couldn't figure out what was going on.

The wire from B6 to terminal 9 was loose...

If you can physically see damage to your headphone jack, then replace it.  If you plug in your headphones and you can see that the contacts aren't lifting off the shorting positions, then this is another reason to replace the jack.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Petricore

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Reply #29 on: October 12, 2020, 04:59:18 AM
Replaced the jack. Much much better engagement with the headphones, but sadly the problem still exists. Really loud in one channel and quiet in the other until the amp warms up.