Standby Mode Upgrade for XA30.5

I’ve been seriously braving the plains of tube amp land for some time, as my >95db speakers afford me that luxury. But the XA30.5 still holds a very strong attraction, if not for these speakers then for another speaker project I have in mind.

However, while I'm hardly any kind of designer, I was never comfortable with this amp’s standby mode, idling the power supply at 15 watts. Relatively speaking, 15 watts really isn’t that small a number, considering that the manual expressly advises to always use it rather than the power switch between listening sessions.

The XA30.5 may be my go-to solid-state amp for a long time, and burning 15 watts all year round is not very earth friendly. Frankly, it makes it less pleasurable to enjoy my music knowing that I’m needlessly contributing to ocean level rise. Call me silly but it’s really not a great feeling.

So it would be nice if one or more of you brainiacs could do something about it.

Class A power amps from Plinius, Luxman and probably have a lot more leaner standby modes. The Luxman M-600A does it at less than 4 watts. Indeed, the Pass XS series standby mode runs at only 1/2 watt!
Pass Labs Xs Amplifiers and Xs Preamplifier .

As the XA30.5 enters its tenth year, there must be others here who are willing and able, even without benefit of the amp’s schematic, to propose a upgrade design for the standby mode-reducing power supply idling to perhaps a much greener ~ 3 watts; maybe less?

It doesn’t seem like a very difficult mod to design and implement. And in light of such huge standby power reductions in the XS series, its certainly a change that should have be made to every solid-state Class A amp that anyone ever built long ago, as we all face the very serious and growing consequences of climate change.

So if someone thinks may know the circuit action behind the XA30.5’s standby mode, why not bounce their upgrade for it off Nelson and Wayne? I bet they’d be up for it.

Please let me know what’s possible and who might be willing and qualified to do these modifications. Thanks.
 
Seriously.

I hate to think what happens to the planet when its actually running.
Thats 200 watts right there.
OMG, won't somebody think of the children.
If 15 watts standby is such an issue, turn it off at the wall or go buy a class D.
Better still, sell all of your greenhouse emitting products, grow some hemp, and make your own clothes etc.
 
Seriously.

I hate to think what happens to the planet when its actually running.
Thats 200 watts right there.
OMG, won't somebody think of the children.
If 15 watts standby is such an issue, turn it off at the wall or go buy a class D.
Better still, sell all of your greenhouse emitting products, grow some hemp, and make your own clothes etc.
Yes, seriously, the point is not to abuse the privilege of enjoying a Class A amp-including the time when you're not using it. And unlike those sharing your useless mocking attitude, at least the Pass Labs designers saw fit to vastly raise the efficiency of the standby mode in their newer series of amps; sadly way beyond my budget.
 
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just turn it off
if you have 1 hr between sessions , then yes , but if you have more than 6hrs , then turn it off

regarding XS stand by power consumtion , that's probably just from small auxiliary xformer and rest , which role is to fire up big ones

so - in that case , main shebang is Dodo , while on stand by
 
Looks like it's not a problem, just turn it off!

When not actually intending to play music the amplifier should be left in standby mode, where it draws only a few watts of bias on the output stage. If you wish to reduce the power draw to 0, you can shut the amplifier off via the rear panel switch, however we recommend that for minimum noise this switch should be toggled in stand-by mode.
 
You could put in a service request at pass labs......

I have permanent service ticket at PL

though , they learned through years to ignore it

who's to blame - moi , or them?
 

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