Equi=tech 2Q transformer hum, other options?

I bought two 1.5Q's. One hummed and one did not. Equitech replaced the transformer in the one that hummed (within the warranty period) and that fixed the problem.

I would have hoped Equitech would reject these units during QC testing.

I recently got a 2Q used (made in '05, with 10 outlets instead of current version's 12, but as far as I know Equitech's Plitron LoNo transformer remains the same). My example is silent and makes no detectable vibration. (I note however that it doesn't reduce the degree of transformer hum I get from one of my connected amps. The 2Q is also plugged into an Exact Power EP15A powerline voltage/waveform-correction unit, but again this doesn't have any effect on transformer hum with my amp, so I assume it doesn't with the 2Q either.)

In any case, when I spoke with company president Martin Glasband he assured me that the lifetime warranty on the transformer itself is transferrable (with no special registration required), and commented that they've only needed to replace a couple of these in their history. Guess you're one of the lucky two JJ, and Hatari's experience may indicate one reason why.

My take: If you can hear the hum from the listening seat with the house's HVAC fan running but no music playing, it's unacceptable. If on the other hand you can only hear it when closely approaching the unit itself, or not from the listening seat unless the house-fan is off, then I'd say Equitech and 6Moons have it about right and you might be making too much of something that shouldn't really be an issue.

(If this criteria for my opinion seems arbitrary, I'm basing it on the fact that where I live in the mid-Atlantic region, maybe only a month's worth of days out of the year could I listen for any length of time without either having the house's climate-control system or fan turned on, or the windows open, either of which increases the level of background noise in my main-level listening room to the point where I can't hear my amp's transformer from the listening seat. For those of you with windowless or subterranean dedicated listening rooms, who don't mind air that's stale, stuffy or chilly on those other 335 days, or are located in paradise rather than anywhere along 95, well hey, please feel free to ignore. Complete background silence would certainly be nice in a perfect world!)

Are Equi=Tech Model Q's really made by Plitron? Why are they so much bigger than a similarly rated Plitron unit?

It may be due to DC in your powerlines. There's an active thread on this in Tech Talk. I had this problem with my Isoclean power conditioner. Inserting the Channel Island XDC-2 between the wall outlet and the Isoclean completely eliminated the problem. But the XDC-2 must be used within its specifications. Mine is used only for front-end equipment.

Ironically, transformer-based (balanced) power conditioners are subject to DC-associated transformer noise.