Meanwell SMPS (e.g. RS-25-12) with a LDO after is a pretty good DC source. But it needs an LDO.
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I have only had one PC SMPS fail and that was because the fan vent became blocked with dust. Unblocked it and it has been fine since for many years.
Ah both my ST120s (one stock, one modded) are long gone, along with a couple modded AR-XA TTs, my trusty Micro Seiki TT and several tone arms.
My ST70 sits on a shelf but a ST400 effortlessly drives my subs.
The technical content has been kind of fluff so far. There are many specs to evaluate the performance of a PSU beyond noise. Also, short MTBF's that some use to conflate planned obsolescence with technical limits are irrelevant. Would love to hear from the gurus why there aren't any switching super regulators, at least not in the DIY world that I know of.
Linear Audio Silent Switcher MkII – diyAudio Store
It's too small to order yourself but combines the best of switching tech with analog LDO.
It's too small to order yourself but combines the best of switching tech with analog LDO.
They're out there, but as you noted they're kind of rare.
The prime reason for this is that SMPS design is not for the light hearted. It's a specialty all of it's own, quite often beyond the knowledge and resources of your typical DIY hobbiest. It's both easier and cheaper to buy than build in this case.
I'd like the hive's opinion on another product I'm cynical about.
Inverter generators are being pushed hard over the traditional copper & iron versions, for reasons similar to SMPSs, but good inverters (alone) are often more expensive than the entire generator.
I suspect there's some major corner-cutting going on. Amiright?
Inverter generators are being pushed hard over the traditional copper & iron versions, for reasons similar to SMPSs, but good inverters (alone) are often more expensive than the entire generator.
I suspect there's some major corner-cutting going on. Amiright?
An alternator/inverter is quite different from a battery/inverter.
Working higher than line freq reduces the iron needed, and this alone may pay for a board of parts.
Working the alternator 3-phase instead of single-phase saves something.
Stepping up from battery voltage needs high current and a transformer; the alternator can deliver line voltage directly so just a matter of re-slicing to 50/60Hz.
The available energy from an engine-alternator is strictly limited; the short-term energy from a big battery is un-limited.
The "killer" advantage for the customer is the engine does not run a multiple of 50/60Hz, it can throttle-back on light load. Less noise, less fuel.
But of course there is major corner-cutting, if you shop by price.
Working higher than line freq reduces the iron needed, and this alone may pay for a board of parts.
Working the alternator 3-phase instead of single-phase saves something.
Stepping up from battery voltage needs high current and a transformer; the alternator can deliver line voltage directly so just a matter of re-slicing to 50/60Hz.
The available energy from an engine-alternator is strictly limited; the short-term energy from a big battery is un-limited.
The "killer" advantage for the customer is the engine does not run a multiple of 50/60Hz, it can throttle-back on light load. Less noise, less fuel.
But of course there is major corner-cutting, if you shop by price.
The problem isn't inherent to SMPS, it's due to cheap or poorly specified ones.
I know of medical devices that have been in the field for 20 years 24/7/365 powered by SMPS without failures.
It is true that many commercial grade devices use as cheap of a supply as they can afford, which often have caps fail earlier than one would like due to ripple current / heat, or low quality.
Will the average linear supply last longer? Probably.
I have 3 Seasonic PC PSUs that are almost 10 years old now and still running 24/7, and they were $100 or a little less.
And you have these in your p.a. rental park and they go out weekly because customers rent them?
I think in the DIY world the reliability is not that big issue. If SMPS fails after 5 years it is easy to replace it (I have a 10 year old PC and it still runs and used everyday). In "Pass" forum there are some projects using SMPS for both pre and power amps and noise level when measuring using Arta or similar is very low and nearly 100% free from 50/60 and 100/120 Hz noise. A common mode choke as post filtering is very good. I was very much against SMPS in the beginning but now I will consider them and then make a solid post filtering. Brand like MeanWell seems quite reliable. Often the SMPS is a "brick" and placed "far" away from amp (1m or so).
Yes and all run well under their rating.
One even blew out house circuit breaker.
for diy, look at the next 50" samsung flat tv you see out for the garbage. They have a 60 v switcher built in. The one I salvaged had obvious blown 200 v line filter cap, and aluminum foil around the fuse. Shouldn't be too much work to reactivate the supply only, but requires a single supply amp design. I'm building Elvee Ol Fashioned Max but he specified 50 v max. Lots of TO247 Nfets in there too, plus cool 1.5"x3.5" heat sinks.
Reworked a Peavey CS800s switcher supply (blew .160 A fuse, 1000 uf cap in 12 v bias supply on control board at fault) listening to it right now. Put all new 5000 hour up caps in the power supply box. It's a '98 build, about time.
I'd bet real money he picked up a pallet load deal that included a bunch of returns and exchanges from places like Amazon and NewEgg and was ambitiously selling defective stuff back out to the public.
I've purchased about 50 of the things over the past 4 years from multiple suppliers, through Amazon, and haven't yet had a single failure.
You got messed over.
They were off ebay and from China and they took a while to come.
They were replaced with 4 from CPC and not had a problem since.
Interesting they all went with a day or two of each other.
They were replaced with 4 from CPC and not had a problem since.
Interesting they all went with a day or two of each other.
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