question for Luxman L-590AX owners

From the posts on this thread and the other one linked to above it appears it is an issue that tends to develop after years.

I took a look at the Luxman class A release history to try to guess when the new versions of class A integrateds might be released, in hopes that perhaps this issue gets addressed. But if the issue goes back to past generations, who knows if having such hope for correction is even warranted??

Anyway, near as I can tell:

L590A was released in 2005
L590Aii was released in 2010
L590AX was released in 2013
L590AXii was released in 2016

Would seem that a new release should be soon if past is prologue, given that we are now into 2021.

@builder3 

I'd be interested in hearing your thoughts, jjss49.

i don't know what to say really...  saying class a amplification is an unavoidable factor in creating transformer hum is a new one to me, and i think it is a pitiful and lame excuse - i have had class a amps from pass and others they do not hum - and it has been a few years since i have had a luxman amp in house

hum can be caused by low line voltage as others have mentioned... maybe check your line voltage?  

otherwise, if you can try to see if the retaining bolt(s) to the major transformers in the unit are as tight as possible... sometimes with age, transport, movement, they can loosen...

good luck

Yeah, no kidding. Seems like a solvable problem to say the least. C’mon Luxman, figure it out!

That’s why I really wish I knew how prevalent it was. 5% of units? 20%? 50%?

Helpful if others who have the units and have never had any buzz/hum issue post up as well. Maybe it is a very small minority? Fact that some users who've had multiple generations and all hummed could mean more widespread, or could me line issues if all happened in same house, or combo of both.  But if Luxman dealers actually admitting it is an issue, then that is more telling.  Dunno

@builder3    Can we go back to basics?  Would I be right in assuming that you've had other integrated amps or power amps in the same house that, when plugged in, didn't hum?

We also have reports of exactly the same model humming in other people's houses, and also occasionally examples of the same model with no hum.

From this I conclude that it's either:
-an interaction of the design of the amp with the power supply; some feature of the design makes it susceptible to hum in many but not all situations;
-a QC issue of many (but not all) examples of the transformer used in that model.

Lot of this has been covered. This exact integrated amp has been dead quiet since I've owned it, which has been 3-4 years, up until a couple of months ago, when the hum started. It's been plugged into the same outlet since day one. I just now checked the voltage at the wall, 121.2-121.6VAC. Tested several other outlets in the house, all in the 120-121V range. The panel is 10 years old, professionally installed. The PUD service drop is new, although the line feeding that is pre-existing. Same with my shop, with the exception that I wired it. Same service drop to parallel feeds into a 400A meter base, one set of feeds serve the house, the other set serve my shop. The amp has been powered up in both buildings with no difference, so unless the power company has a new issue, I'm ruling out our power.
I'm leaning heavily towards an issue with the transformer in the amp itself, or so it seems to me.
I'd feel more comfortable taking it apart if I could find a service manual.