BH crack buzzing noise

[wiener4hire]

Before i begin i'd like to say i am a complete nube, this is the first soldering i have ever done.

So i just recently got my Crack up and running, haven't installed the speedball i got with it yet though. There is however a buzzing noice coming through the headphone. It is primarily in the left ear, but is also present in the right ear to a lesser extent. It doesn't matter how loud the volume is, and is there both when playing music and not, it is loud enough to be a constant nuisance. Anyone have any idea why this is?

[wiener4hire]

Just adding that the buzzing is a very low frequency, probably around 50 hz.

[Paul Birkeland]

Were the voltage and resistance checks all within the limits?

Does the buzzing persist with a source plugged in?

[wiener4hire]

Both were within the limits yeah. I did however not do the final test with the jack itself, simply because i couldn't quite figure out what exactly they wanted me to do. I just plugged in some cheap headphone i had lying around, and it made the buzzing sound. Same with other headphones. And it also persists when plugged in.

[JamieMcC]

What is your source chain?

If you are using a pc or dac streaming try connecting by usb instead also try a different source completely such as a cd player, record player to see if the noise is still present.

[wiener4hire]

My source chain goes USB -> Aune T1 -> RCA -> Crack -> HD 650.

I jsut tested from a CD player, and it was the exact same. I noticed something odd though. When i was about to power the Crack off, i was still wearing my cans, and my hand just touched the big tube. That changed the buzzing significantly. When i touch the tube it gets a lot louder, but it doesn't do anything when i touch the smaller tube. Don't know if that helps.

[JamieMcC]

OK the cd player was direct to the Crack without the dac in the chain? Can you try putting a few twists in your rca cables that connect the dac to the Crack and listen again the Crack is very good at picking interference from wifi routers and other electrical equipment check the routing of your cables try and route any power leads away from your RCA interconnects.  This should help eliminate some of the possible basic external causes and the Bottlehead team will help on anything that might be internally related.

[wiener4hire]

Yeah, the DAC was not in the chain. I don't really get what you mean by "Can you try putting a few twists in your rca cables that connect the dac to the Crack and listen again"?

I also tried moving it to another room with the CD player, and it was the same. I doubt outside interference is the problem.

[Doc B.]

Try removing the 6080 and cleaning the pins with something like a scotchbrite pad or with Deoxit. It might just be flaky contact.

[JamieMcC]

Yeah, the DAC was not in the chain. I don't really get what you mean by "Can you try putting a few twists in your rca cables that connect the dac to the Crack and listen again"?

I also tried moving it to another room with the CD player, and it was the same. I doubt outside interference is the problem.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fcdn.head-fi.org%2F7%2F7a%2F900x900px-LL-7ab2aec2_0092.jpeg&hash=3e0ef8569287b83ec1fec5d7e3f8b0b88ec0a737)

[wiener4hire]

Unfortunately i have none of that on hand, i can get it soon though. I just unplugged the 6080 and took these two pics of the pins, do they look good?

http://imgur.com/hZ4qLXQ

http://imgur.com/fhMWdpV

[wiener4hire]

Unfortunately my RCA's are cheapo cables like shown in the pic i linked below so i doubt that will do much. Do you think the cables could be the problem?

http://imgur.com/stdMSYI

[JamieMcC]

You could try moving them around while listening and see it the buzzing changes or stops momentarily whilst doing so. If it doesn't change then it most probably isn't the cables.

[wiener4hire]

Tried that already, and it didn't do anything.

[Doc B.]

You may have a bad solder joint that is causing the noise, or you may have pins on the tubes that need to be cleaned. Try reheating any suspicious looking solder joints, particularly those associated with the 6080 socket and, as I have already suggested, try cleaning the tube pins.