Crack Hum

[riskybusiness]

Hello,
I have a fully built crack, but there's a hum when connected to and not connected to sources. Is this normal?

 

[Doc B]

No it's not normal unless it is very faint hum when used with very efficient headphones (for example Grados, which the Crack is not designed to be used with). Is this a Crack you built, or something you bought used?

 

[riskybusiness]

I built this crack

 

[riskybusiness]

ive used only hd6xx and zmf auteurs

 

[Doc B]

Does the hum have a buzzy edge to it? Is it loud or soft? Most often a buzzy hum is due to a cold solder joint where the black wires connect to the headphone jack. If it goes up and down when turning the volume control it can be noise being picked up by the interconnect cables. If it is not very loud or buzzy it can be magnetic interference from a nearby power transformer or it could possibly be a noiser than average tube.