Loud hum - Drip EQP1A V2

[RayBlack]

Hello,

I have a problem with one of my Drip EQP1A V2.
There is a lot of hum and I don´t know why.
I built up two of them at the same time so they are bulit up identically and with the same parts.
One of them works perfect, the other has a loud hum in the signal.
I replaced all the electrolytic capacitors but the hum is still there.
I also checked all the soldering points and they are Ok, too.

Is there anybody who can help me with this problem?

Kind regards

 

[Pip]

Check all your ground points and make sure they are solid and that they are identical on both builds. Then check that your interconnects to your system are the same and that those are properly grounded, the easy way to do this to replace the good unit with the bad using the same integration connections and see if the problem is the same,  It sounds to me like a ground loop. Which could be either an audio or a power ground issue and might be interrelated.

Pip

 

[ruffrecords]

When the unit is warmed up, switch off. Does the hum disappear straight away or does it die slowly?

Cheers

Ian

 

[RayBlack]

Thank you guys. We actually found out, that the soldering holes for the tube-sockets were too big and the solder shorted two of the holes...that was a long search but an easy fix!