I think we will more or less be forced to use SMPS out of necessity. A variac is a choice too. The range/fluctuation will be too wide for transformers to be ignored.
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SMPS are not always suitable power sources, and the good ones are expensive. One thing for sure in my experience, old style brute force power supplies last forever. Not even close to true for SMPS, the capacitors they use get beat up in a small form factor and die. They need to lower operating temperatures to make them last, and use quality parts. I rebuild using Poly-Aluminum capacitors, which drops hash on the output as well.
Yes, my small devices are all unreliable. I would refuse to buy a class D or SMPS type power amp or preamp.
Yep, spent the pandemic going through everything, the 'chopper' chips go and the caps. Replaced quite a few SMPS with coil transformers , that is what the mains network is designed for and works best with.
Difficult to better a potted toroid and a good hefty choke inductor.
...and that short termism argument that SMPS are cheaper, smaller more efficient, Oh the carbon foot print!
Not when they fail within a few years. Not if they destabilise sensitive digital devices. Not if they give you headaches or ear aches.
None of my coil PSU's have failed, They don't destabilise with digital devices, they don't give you headaches. Updating the noise filtering in some coil PSU's has been required in some areas, because of the huge uptake in use of SMPS's and the LF-MF hash they they inject back into the mains.
On a couple of occasions transformers lost the cohesion of their varnish and get noisy with the 50Hz , but that's across three decades! One of those I fixed recently by dripping superglue into the extra shield on an EI tran. A quieter transformer resulted.
Its possible to take some transformers that have lost cohesion in the windings to an electro motor refitting company and get them to dip it in their ultrasonic varnish bath and then heat cure them, what could be more environmentally friendly. Renewing something that was reasonably well designed in the first place.
Its an interesting fundamental to design a Power supply primarily with coils to achieve as much as possible, then add everything else.
Not when they fail within a few years. Not if they destabilise sensitive digital devices. Not if they give you headaches or ear aches.
None of my coil PSU's have failed, They don't destabilise with digital devices, they don't give you headaches. Updating the noise filtering in some coil PSU's has been required in some areas, because of the huge uptake in use of SMPS's and the LF-MF hash they they inject back into the mains.
On a couple of occasions transformers lost the cohesion of their varnish and get noisy with the 50Hz , but that's across three decades! One of those I fixed recently by dripping superglue into the extra shield on an EI tran. A quieter transformer resulted.
Its possible to take some transformers that have lost cohesion in the windings to an electro motor refitting company and get them to dip it in their ultrasonic varnish bath and then heat cure them, what could be more environmentally friendly. Renewing something that was reasonably well designed in the first place.
Its an interesting fundamental to design a Power supply primarily with coils to achieve as much as possible, then add everything else.
True, and that would be a relatively cheap option. Less convenient because every time you fire your system up (unless you let everything on 24/7) you have to check. My variac has a digital indication display for incoming and outgoing voltage, happy with that. The other option is go off-grid but then with different downsides. For consistently higher voltages (or lower) one could consider a buck transformer.
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Wow, you have a extraordinary power company. Mine, based on past experience, would hardly be that compliant.