DC blockers - what's your experience

I use iFi on my NAS and fiber transmitter….they work excellent and are extremely affordable. 

I had major problem with transformer hum that lasted for years, this along with over voltage issue(124-126v). Never could get rid of transformer hum, bucking transformer for the over voltage. Suddenly one day I come home no more transformer hum, voltage down to 119-121v, this has remained for years now. Seems electrical grid was finally repaired.

Power is primarily clean here where I live do have an LessLoss 640x on my LessLoss DAC and audiolab dc blockers on my digital and analog FEU. More for assurance than anything else. Amps are right into the wall. 

 

 

Also new hook up terminations. Aluminum wire terminations start to corrode and loosen over time when exposed to the outdoors environment. Sun’s rays, heat, cold, rain, wind. All will break down a tight, clean, low impedance termination. A poor termination can and does cause excessive harmonic distortion on the mains.

I do not think that UV and heat affects aluminium, unless the global worming is higher that I believe it to be.
And there is no “clean connection” with aluminium, as the stuff naturally gets a layer of alumina on it in a hurry. The pickle it with hydrofloric acid before it is bonded… so it always has the tunneling happening…

But then again, which does, or what do, harmonics have to do with DC blocking?

So far we have two things that are not known, or shown to exist on the OPs power that need to be fixed.
It is like an SNL skit of an AA meeting with testimonial stories of what was done to fix these “problems”.

Personally I would be spending $100 on an electrician before fixing a problem that has a chance of being non-existent. There are many real problems that likely need fixing that could happen first.