Detecting “Dirty” Power


I bought a used BHK 250 still under warranty. It is plugged into a Denali S power conditioner.  I heard a hum coming from the area around the tubes.  I cannot hear it from my sitting position and it doesn’t effect SQ, but I want it gone.  

I sent it to PS Audio; they tell me there is no hum and sent it back. They implied I mostly likely have a power problem and recommended some troubleshooting steps.  I unplugged everything from the 250 and plugged it straight into the PS Audio receptacle.  The hum is still there, but it is not as pronounced.  A P15 power regenerator might fix the problem, but I want to know if I have a power problem before I do anything.

How can I determine the quality of the power coming into my house and out of the receptacle? FYI, the Denali is plugged into a PS Audio receptacle/dedicated 20 amp line.  I have a whole house generator w/ transfer switch and whole house surge protector. 
128x128oldschool1948

Showing 2 responses by vinylzone

If it is a transformer hum, you might have a dc offset problem.  This is usually caused by some other device or appliance on the same circuit.  You either need to figure out what it is, or get a dc blocker.
I don't know about the first link.  It won't block dc offset, and makes some "interesting" claims.  The AVA is what you should try.  Alternatively, Emotiva makes one too:  

https://emotiva.com/collections/accessories/products/cmx-2

I haven't tried it yet, but was going to order one shortly.  Both that and the AVA should work if the problem is indeed dc offset.